Fossils Of The Miocene Dam Formation Of Qatar (2009)

A Fossil Hunting Guide to the Miocene of Qatar, Middle East A Geological & Macro-Paleontological Investigation of the Dam Formation

By: Jacques LeBlanc Geologist, BSc.

October 2009

Fossils of the Miocene Dam Formation of Qatar

A - CONTENTS A - Contents B - Contacting the author C - About Qatar D - Foreword E - Methodology F - Conventions and Mapping Legend - GoogleEarthTM G - Disclaimer 1.0 - Previous Surface Geological and macropaleontological investigations of the Dam Formation 2.0 - Regional geology of the Dam Formation 3.0 - Detailed stratigraphy and Environment of Deposition of the Dam Formation in Qatar 3.1 - General 3.2 – Salwa Member (General) 3.2.1 – Lower Salwa 3.2.2 – Middle Salwa 3.2.3 – Upper Salwa 3.3 – Al-Nakhsh Member (General) 3.3.1 – Lower Al-Nakhsh 3.3.2 – Middle Al-Nakhsh 3.3.3 – Upper Al-Nakhsh 3.4 – Abu Samrah Member 4.0 - The macrofossils of the Dam Formations in Qatar 4.1 – Vertebrates 4.1.1 – Pisces / Fish (Sharks, Rays & Teleosts) 4.1.2 – Mammals (Sirenia/Dugongs) 4.1.3 – Reptiles 4.2 – Marine Invertebrates 4.2.1 - Arthropods 4.2.1a – Leucosiidae (Crabs) 4.2.1b – Callianassidae (Mud Shrimps) 4.2.2 – Echinoderms (Sea Urchins) 4.2.3 - Corals (Scleractinia) 4.2.4 - Bryozoa 4.2.5 - Mollusks 4.2.5a - Bivalvia 4.2.5b - Gastropods 4.3 - Miscellaneous 4.3.1 - Stromatolites 4.4 - Plants 5.0 - The main minerals 5.1 - Gypsum 5.2 - Nodular anhydrite or chicken-wire structure

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Fossils of the Miocene Dam Formation of Qatar 6.0 - Geological features 6.1 - Beachrocks 6.2 - Oolites 6.3 - Aeolianite 6.4 - Hummocky Cross Stratification 6.5 - Tepee Structures 7.0 – Acknowledgments 8.0 - Recommendations and Conclusions 8.1 - Recommendations 8.2 - Conclusions 9.0 - References 10.0 - Recommended literature 11.0 - Appendices 11.1 – A brief introduction to Carbonates 11.2 – Little known facts about the Dam & Hofuf formations 11.2.1 – Ventifacts distribution in Qatar 11.2.2 – Why is there contamination of sulphate in the Hofuf formation: the answer lies in the Dam formation 11.3 – Glossary & Coordinates of the main geographical localities 11.4 – How to load and use our geological mapping package in GoogleEarthTM 11.5 - The Rock-Carvings at Jarr Umm Tuwaim 11.6 – GPS Points details 11.6.1 – Area 1 11.6.2 – Area 2 11.6.3 – Area 3 11.6.4 – Area 4 11.6.5 – Area 5 11.6.6 – Area 6 11.6.7 – Area 7 11.6.8 – Area 8 11.7 – Links to all picture Web Albums 11.8 – Vertebrates of the Dam Formation in Saudi Arabia 11.9 – Dam Formation Poster

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Fossils of the Miocene Dam Formation of Qatar

B - CONTACTING THE AUTHOR [email protected] http://leblanc.jacques.googlepages.com/fossilhome NOTE: Please do keep in touch in order to provide me with 1) the locality information of your own personal fossil and mineral finds in Qatar and, 2) your knowledge of pertinent articles for which I may not be aware of. This information will be useful to publish again on the geology and paleontology of the country. I will also be delighted to answer all the questions you may have.

C - ABOUT QATAR The State of Qatar is an independent emirate (monarchy) of 11,400 km2 with officially 1,400,000 inhabitants (2008); 20% of whom are Qataris and the rest are largely other Arab groups together with Asians and Europeans. About half of the population lives in Doha, the capital and commercial center of the country, located on the eastern coast. The country is largely a barren peninsula in the Arabian Gulf, bordering Saudi Arabia. The economy of Qatar is dominated by oil and natural gas, which accounts for 70% of export income. Oil and gas revenues have been used to diversify the economy, including the development of chemicals, steel, cement, and fertilizer industries and banking. Arabic is the official language, but English is spoken almost everywhere. Its citizens embrace the future with unswerving optimism and enviable potential. Hospitable, generous and kind, Qatari's make visitors to their country feel very welcome. Qatar is an ideal family location and a very safe place to visit, live and work. Standards of living are high as the infrastructure continues to develop rapidly. During the summer months (May to September), temperatures generally average 35°C, but it's not uncommon for the mercury to rise much higher (see the chart below). The 90% humidity that comes with this time of year hangs over the peninsula and sandstorms are frequent throughout the year, especially in spring. During the winter months (December-February) there is the odd shower but the days are mild and pleasant and evenings are cool. Rainstorms, however, can also hit the country in December and January.

Figure C-1: Average Temperatures in Doha throughout the year (www.weather.com )

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Fossils of the Miocene Dam Formation of Qatar

D - FOREWORD The present document discusses the geology and macrofossil content of the Miocene Dam Formation of the State of Qatar for the following purposes: A) amateur fossil & mineral hunting, B) mapping of the various horizons within the Dam Formation, and C) recommending to the State of Qatar the geological and paleontological localities worth protecting/preserving for the benefit of studies and/or enjoyment by the public at large and future generations. Several document types are part of this study and should be viewed/downloaded all together from the author’s website. They are: A

The main pdf text document (the one you are currently reading) which also includes a poster in the appendix 11.8 (last page of this document);

B

One KMZ (GoogleEarthTM) file containing all interactive GPS points and mapping units over the areas studied for this research. Assuming that you are currently reading the digital file (pdf) of this main document, another option to download the KMZ file to your computer is to right click on the “paper clip” icon to the right and select “Save embedded file to Disk…”. When you use the KMZ file, make sure the GoogleEarthTM program is set to be used with decimal degrees (dd.dddddº).

C

Over 400 pictures found in an online album which is accessible from the author’s website or appendix 11.7 of this document. The pictures can also be downloaded to your computer from the album. The author took the pictures during the course of his multiple field trips and since there is no copyright on these images, feel free to use them as you wish. You will find several pictures pertinent to the geology & paleontology of the Dam Formation and few pictures dealing with non-geological items found at some localities.

Therefore, in order to make full use of the information provided, the reader should have access to • The latest version of Adobe Acrobat Reader (http://get.adobe.com/reader/ ) • At least version 5 of GoogleEarthTM ( http://earth.google.com/ ).

E - METHODOLOGY The present publication is the “Main Document” which discusses the geology and fossil content of the Dam Formation of Qatar from a macroscopic point of view, with references to some nearby areas in Saudi Arabia. To put together this document, an in-depth literature research was performed and countless field trips were made to gather new information. All this data was then collated together to make up this reference guide. It is estimated that the Dam Formation covers an area of about 912 km2 (8%) of the total surface of the country. Because of this huge area to cover, it was decided early on to divide the formation’s occurrence into eight (8) onshore and one (1) offshore geographic areas (Figure F-1). The mapping would take place only in two onshore areas (1 & 2) for the purpose of this present publication and all other areas would be visited, if possible, in order to ascertain the physical makeup of the formation and its paleontological potential. It turned out that areas 1, 2 and 3 were the ones most extensively studied while areas 4, 5, 6, and 7 were visited just briefly; these could be part of a future study on the formation. Area 8 could not be visited due to some permit restriction that could not be overcome. The offshore area itself (Ishat island) was not visited either due to the lack of an opportunity (boat ride), however if such opportunity presents itself in the future, the author’s website will be updated with the new information. http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar Areas 1 & 2 were selected for mapping purposes because of the following main reasons: Proximity to a main road No permit required to access the land B No mining activities (except in area 2; however the current gypsum quarrying activities are kept to a minimum) A small sector within area 1 was studied by several authors in the recent past, such as Dill et al (2005 & 2007) and Al Saad (2002a)

A C D

In order to assess and measure all the GPS points the author either walked to or drove to each of the localities described. The only available days of the week available to do field work were Friday’s. A typical Friday started with an early rise at 6AM and arrival in the field by 8AM. Return to Doha was normally just before sunset at 6PM. The evenings of the following week were used to compile, map and document the gathered field information. The geology and paleontology of the Dam Formation in Qatar has been summarized in the present pdf document. However, the pictures taken during the course of our exploration and the accompanying interactive GoogleEarthTM file which was created to map the various geological levels of the formation and help us position all our GPS Points, give a better representation of the extensive work accomplished. We recommend the reader to make good use of them. All coordinate points were accurately measured (+/- 3m) using a Garmin GPSmap 60CSx. Qatar does have a Map Datum [the Qatar National] and a Position Format [the Qatar National Grid -QNG], however it was decided at the start of this project to use the WGS 84 Map Datum with decimal degrees (dd.ddddd) for ease of use by all our readers, wherever they might be in the world. In the present publication, we are using the sub-divisions of the Dam Formation established by Dill et al (2005 & 2007) as described further below. An attempt is also made to unify the sub-divisions presented by former authors with Dill’s more recent and thorough investigation. We have mapped only the Members and sub-Members of the Dam Formation. We did not map the loosely occurring Pliocene/Hofuf gravels and the Quaternary sands covering it. Where the Dam Formation is overlaid by these sediments, we have attempted to correlate the hidden member(s) with the nearest exposed outcrops. When consolidated Pliocene/Hofuf sands/gravels were found, a GPS reading was taken. Note: To learn more about the loosely occurring Pliocene/Hofuf gravels and the interesting phenomenon of ventifacts, please read Appendix 11.2.1 Finally, GoogleEarthTM was selected as the GPS point locater and mapping software of choice for several reasons: • • • •

Easily and freely accessible and downloadable worldwide; Simplicity of use; Offers regularly updated satellite images which can be used to correlate the strata of the exposed Dam Formation and to observe the natural and manmade changes that have occurred over a given time period. Compatibility of GoogleEarthTM with all Garmin GPS

GoogleEarthTM, however, is not the package we would have selected for an in-house surface mapping project. We find that this program has not yet reached its full capacity as a mapping software, especially when comes to polygon colour-infilling. Several flaws were indeed encountered with this feature; these make it difficult to deliver a professionally looking product for a project similar to the one at hand. Therefore, you will notice that the geological sub-units of the Dam Formation were mapped without polygon colour-infilling. Instead, thick coloured contour lines were used to delimitate the top of every sub-units, as seen in Tables F1 & F2 and fig 11.4.4.

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Fossils of the Miocene Dam Formation of Qatar

F - CONVENTIONS AND MAPPING LEGEND - GoogleEarthTM Colours of Contour lines

Dam Sub-Units

GPS Points numbering system

BLACK

Top of Abu Samrah

From 7001 to 7999

DARK BLUE

Top of Upper Al-Nakhsh

From 6001 to 6999

ORANGE

Top of Middle Al-Nakhsh

From 5001 to 5999

YELLOW

Top of Lower Al-Nakhsh

From 4001 to 4999

PURPLE

Top of Upper Salwa

From 3001 to 3999

PALE BLUE

Top of Middle Salwa

From 2001 to 2999

GREEN

Top of Lower Salwa

From 1001 to 1999

Table F-1: Mapping conventions. Example: GPS point “A1_5001” means locality 5001 of the Middle Al-Nakhsh Member in Area 1, while “A2_3005” means locality 3005 of the Upper Salwa Member in Area 2.

Locality of a general geological nature Important fossil echinoderm (sea urchin) site Less important fossil echinoderm (sea urchin) site Important fossil dugong/sirenian remains site Less important fossil dugong remain site or potential area to explore for dugong remains Important fossil bivalves site (normally the base of Upper Salwa) Less important fossil bivalves site (normally the base of Upper Salwa) Well developed [large] Stromatolite mounds (top of Middle Al-Nakhsh) Weakly developed Stromatolite mounds (top of Middle Al-Nakhsh) Miocene lithified sand dune/interdune (aeolianite) Consolidated or unconsolidated Miocene sand which has not developed into a dune or interdune feature “Desert Rose” forming at the surface of this Holocene sabkha (no digging required) The author’s notes about a non-geological item found at that locality A known geographical point of Qatar Table F-2: Icons used for the GPS points in GoogleEarthTM http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar

Fig. F-1: The eight onshore and one offshore areas of the Dam Formation in Qatar

G - DISCLAIMER This research was compiled for your enjoyment only. The author does not take any responsibilities for injuries or accidents that may be inflicted to the amateur or professional fossil hunter during a field trip in locations described in this document. The reader should always apply common sense while in the field and be prepared accordingly for the outdoors. It is also the reader’s responsibility not to venture on land(s) that belong to the Government, especially those currently used for military purposes. It is important to note that the author did not get any special permit from the Government to visit the localities mentioned in this publication. It was assumed from the beginning that there was no restriction whatsoever to visit them. After further insight, however, the author recommends the reader not to visit Area 8 (we did not visit it either) and the southern portion of Area 3 near the Qatar – Saudi Arabia border unless the appropriate authorizations have been secured.

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Fossils of the Miocene Dam Formation of Qatar

1.0 Previous Surface Geological and macropaleontological investigations of the Dam Formation • • •

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Philby, H. St J. (1933) reports the first fossil find in the Miocene of Eastern Arabia (in what would be later named the “Dam Formation”). Its locality was at “Qarn Abu Wail” which is today separating Qatar with Saudi Arabia. Steineke and Koch (1935) introduce the name of “Dam” in an unpublished Aramco report. Thralls and Hasson (1956) formalized the Dam Formation. The type location of the Dam is at Jabal al Lidam in Saudi Arabia (Lat 26º 21’N, Long. 49º 27’E) about 60 km west of Dhahran where the lower part of the type unit crops out (fig 1.1). The lower beds of the formation were measured in the eastern face of Jabal al Lidam and the upper part of the 89.8m interval were measured at Al Umayshir (Lat 26º 17’N, Long. 49º 24’E). At these two localities, it consists mainly of marl, chalky limestone and clay, interbedded with thin beds of sandstone. It is unconformably overlain by the Hofuf Formation (fig 1.2) Powers et al (1966) recorded echinoderms, molluscs, ostracods, corals, fossil wood, vertebrate fragments, crab claws and foraminifera from the Dam formation carbonates (see his section in fig. 1.2) Cavelier (1970a&b) subdivided the formation into the lower and upper Dam subformations (figs 3.7 to 3.11) Johnson et al (1971) spent 10 days in the field investigating the Miocene Dam Formation in Qatar with an emphasis on determining the regional dip by recording elevation and location of reliable marker beds on both flank of the ridge. Sugden et al (1972) describes all the surface and sub-surface formations of Qatar; including the Dam. Kier (1972) studies the tertiary echinoderms (including the Dam Formation) of Saudi Arabia Cavelier (1974) summarizes the fauna and lithology of the Dam Formation and all the others outcropping at the surface of Qatar Dr. J. Roman (1976) published his study on the Eocene and Miocene echinoderms of Qatar in which he describes specimens from the Dammam and Dam Formations in localities such as Zekreet (Eocene) and Qarn Abu Wail (Miocene). Seltrust (1980) described the result of their 1978-79 field work to map the country of Qatar which had been commissioned by the Director General of the Industrial Development Technical Centre. All of the outcropping formations, from Tertiary to Recent age, are described systematically and identified fossils are listed. A supplementary part of this programme was the production of an updated geological map, at scales of 1 : 100,000 and 1 :200,000, using as a base the new 1 : 100,000 topographic maps, prepared in 1980 by Hunting Surveys Limited for the Ministry of Public Works, Engineering Services Division. Thomas et al. (1982) studied the the remains of rodents and larger mammals, reptiles and birds from the Dam Formation of the As-Sarrar region in Saudi Arabia. Abu-Zeid and Khalifa (1983) modified Cavelier’s work and divided the formation into members “A” and “B”. They also investigated the clay components of the Dam formation in Qatar. Hunting (1983) were commissioned in 1982 by the industrial Development Technical Centre, Doha to produce and interpret a digitally enhanced Landsat Multispectral Scanner (MSS) false colour mosaic. The format and scale (1 :200,000) of both the mosaic and the interpretation map were to match a photogeological map of Qatar produced by Hunting Geology and Geophysics Limited in conjunction with Seltrust Engineering Limited (see above). This study of Landsat has confirmed the regional geological picture built up during http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar

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• • • • •

•

•

•

the earlier photogeological work. It also stressed that collapse structures due to solution of evaporites are more widespread in Qatar than hitherto thought. Hilmy et al (1987) studied the petrography and sedimentology of the argillaceous rocks of the Dam in Qatar Irtem (1986) provided detailed study on the stromatolites that occur in the lower part of the Miocene Dam Formation in Saudi Arabia. He concluded that the Dam Formation consists of three upward-deepening cycles in Al Lidam area and was deposited in a shallow subtidal to lower intertidal environment Hewaidy (1991) studied for the first time the foraminifera of the formation in the Jebel AlNakhsh and Al-Kharrarah areas where they were dated as Burdigalian-Helvetian (Early to Middle Miocene). El-Kassas (1992) studied the natural gamma radioactivity of all Qatar. He concluded that the cause of radioactive anomalies recorded in the Lower Dam limestones is mostly the presence of some vertebrate remains (bones, teeth and coprolites) rich in phosphate. Khalifa and Mahmoud (1993) identified three types of algal stromatolites in member “B” (or Al-Nakhsh member equivalent of Dill et al) of the Dam Formation at Khashm Al-Nakhash. They proposed a protected tidal environment for the deposition of the formation. Jones & Racey (1994) published facies distributions of the Miocene in the Middle East Al-Saad and Ibrahim (2002) studied aspects of stratigraphy, micropaleontology and paleoecology and found that microfossils are predominantly benthic foraminifera and are represented by 38 species of which most are milioline and one is a larger form. They also stratigraphically subdivided the Dam Formation in Qatar into two new formal members. The basal Al-Kharrara Member [or Salwa member as defined by Dill et al] is made up of limestone, marl, and claystone, and the overlying Al-Nakhash Member is a cyclic assemblage of carbonate, evaporite, and algal stromatolite facies. This study grouped the lithofacies into four major types of which limestone, subdivided into six subfacies, is dominant (Fig.3.6). It concluded that Al-Kharrara member was deposited in warm (25°30°C), clear, shallow waters of the inner neritic zone (0-35 m) that had an elevated salinity (35%-50%) and a vegetated substrate. It also concluded that Al-Nakhash member was probably formed in an oscillating, very shallow-marine environment (0-10 meters deep, including tidal flats), under warm climatic conditions that eventually led to the accumulation of evaporites and algal stromatolites. López-Antoñanzas (2004) and López-Antoñanzas et al. (2004) studied three types of rodents from fossiliferous continental localities of the Dam Formation in the As-Sarrar region of Saudi Arabia. These sites are located about 10 km N-NW of As-Sarrar (26º 59’ 01’’ N; 48º 23’ 14’’ E), less than 90 km from the coast of the Arabian Gulf and about 250 km N-W of Al Hofuf. Teeth and jaw remains were studied Al-Enizi et al. (2006) analyzed samples of recent foraminifera from the nearshore Arabian Gulf and compared them with similar foraminiferal biocomponents of the Dam Formation carbonates at Jabal Midra Al-Janubi. His study indicated that the foraminiferal fossils in the Dam Formation commenced deposition following a slight marine transgression over an eroded Palaeogene surface during the Middle Miocene, under highly adverse, hypersaline conditions. Successive small-scale marine transgressions, with normal salinity, led to foraminiferal colonization and the accumulation of foraminiferal wackestones, packstones and grainstones. These minor fluctuations led to the development of shoaling-upwards cycles, in which the foraminifera and grain sizes responded to increasing energy conditions as well as slight elevations in salinity, as evidence by the concentrations of hypersalinetolerant miliolid foraminifera. Dill et al (2005) and Dill et al (2007) subdivided the succession of sedimentary rocks subjacent to the Hofuf Formation over the Khashm Al-Nakhsh area in Qatar into seven 9 http://leblanc.jacques.googlepages.com/fossilhome

Fossils of the Miocene Dam Formation of Qatar

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lithofacies associations (fig. 3.12a&b). These lithofacies associations were stratigraphically grouped from top to bottom into three members called Abu Samrah, Al Nakhsh, and Salwa Members. Al Nakhsh and Salwa Members both allowed for a refinement of the stratigraphy, each comprising an upper, middle, and lower unit. It is this sub-division that will be used in the present publication. LeBlanc (2008) in his fossil guide to the Tertiary formations of Qatar summarized in general terms the geology and paleontology of the Dam Formation Puls, Jameson & Kozar (2008) put together a carbonate workshop for the Oil & Gas Industry which includes a study of the Dam Formation.

Fig 1.1: Location of the Type Section of the Paleogene-Neogene Formations in the Arabian Peninsula, including the Jabal Al-Lidam locality for the Dam Formation (Al-Sharhan, 1995) http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar

Fig 1.2: Description of the Dam Formation at the type locality of Jabal Al Lidam, Saudi Arabia (Powers et al, 1966)

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Fossils of the Miocene Dam Formation of Qatar

2.0 Regional Geology of the Dam Formation The Dam Formation in Qatar is equivalent to the Dam Formation in UAE and Saudi Arabia and the Lower Fars formation in Iran (Asmari), Iraq and Kuwait. (figs 2.1 & 2.2). The formation in Saudi Arabia and UAE, however, represents a continental environment of deposition as opposed to the one in Qatar which is clearly marine (fig. 2.3). Dill et al (2007) have refined the stratigraphy of the Dam Formation from previous studies by analyzing the Strontium isotopes in all the members of the formation. Their study has yielded a late Aquitanian to early Burdigalian age of sedimentation for the Dam Formation in Qatar. As seen in fig 11.2.8, this would give an age of the formation between 18 and 22 million years.

Fig 2.1: Generalized geological map of the Arabian Peninsula showing (in pink) all the Miocene (and Pliocene) occurrences in relation to Qatar (modified from Al-Enezi et al. 2006).

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Fossils of the Miocene Dam Formation of Qatar

Fig 2.2: Correlation of the Lower Miocene sedimentary sequences along the northeast boundary of the Arabian Platform (Dill et al., 2007) In Qatar, the Dam Formation rocks occur in two discontinuous belts in the southwestern part of the peninsula and forms some of the highest ground (figs. 2.4, 3.2 & 3.3). The more western belt extends southwards, on both sides of the continuation of the Dukhan anticline, from the vicinity of Umm Bab to the border beyond Abu Samrah. The second group of outcrops extend from north of Sawdaa Natheel, in the vicinity of Qulay al Bin Said and Hamir, northeastwards to beyond Al Kharrarah and nearly to the main Doha-Abu Samrah road. The present distribution of this outcrop area is believed to be structurally controlled in part. Dam Formation rocks are also preserved in post-Miocene collapse structures such as at Karanah, Al Markhiyah and Mukaynis (Seltrust (1980)) The Dam Formation strata are occasionally jointed and commonly sub-horizontal with gentle dips indicating post-Miocene movement particularly of the Dukhan anticline. A particular feature of the succession is the development of numerous small domes and basins where relatively steep dips are characteristic. This feature is especially prevalent towards the north of Ti's Karanah (Seltrust (1980)) The Dam formation has unconformable contacts with the underlying and overlying formations. It overlies the Middle Eocene limestone of the Dammam Formation and is overlain by the Late Miocene to Early Pliocene conglomerate and sandstone of the Hofuf Formation (LeBlanc (2008))

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Fossils of the Miocene Dam Formation of Qatar

Fig 2.3: Depositional environments of the Miocene formations in the Arabian Peninsula (Ziegler, 2001). Note the Dam formation with its marine facies (brown) in Qatar and its equivalent continental environment in Saudi Arabia (yellow)

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Fossils of the Miocene Dam Formation of Qatar

Figure 2.4 : Sketch map of the onshore Miocene rocks of Qatar. The Dukhan Anticline extends in NNW–SSE direction along the western coast of Qatar. The dotted bold lines delimit the occurrence of sulphate in the underlying Eocene Rus Formation. The surface expression of the cross-section in fig. 3.2 is marked in the map by the transect A–B (Dill et al. 2005).

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Fossils of the Miocene Dam Formation of Qatar

3.0 - Detailed stratigraphy and Environment of Deposition of the Dam Formation in Qatar 3.1 - GENERAL 0) The Dam Formation in Qatar represents a complete sabkha sequence in Miocene sediments from offshore to continental deposits (Dill et al, 2005). 1) Calcareous and evaporitic sediments (gypsum, celestite) of the Dam Formation in Qatar reflect deposition under subtidal through supratidal conditions, which towards the base and the top of the series are replaced by an environment of deposition more akin to a modem beach. (Dill et al, 2007). 2) All carbonate and siliciclastic sediments younger than the Middle Salwa were subjected to strong dolomitisation, excluding the uppermost part of the Abu Samrah Member. (Dill et al, 2007). 3) The bivalves form a coquina between 1 and 2 m thick [ex.: Upper Salwa, Abu Samrah, etc..] with shells dissolved away by post depositional solution, a fact which applies to nearly all invertebrate fossils found in the Qatar limestones where natural casts are found (echinoids and bryozoa being the exception). The coquina seems to be a "death assemblage" since counts of the articulated valves showed them to be a very small proportion of the isolated valves counted. This unit could be strike walked over several kilometres (Whybrow, 1987) 4) Strike in the Miocene is approximately parallel to the ridge because elevations recorded for the top shale [see Upper Salwa below] on each side of the ridge do not vary a great deal (Johnson et al, 1971) 5) The general dip in the scarp area [Khashm Al-Nakhsh and north of it] (Fig 3.5) is approximately 0.5º to 1º in a direction just south of west (Johnson et al, 1971) 6) Within the Miocene beds there is no evidence of reversal of westward dip. However, the shale outcrop in the flat coastal plain is quite extensive which might either be a result of the leveling out of the Miocene beds, or a result of the suggested westerly thickening of the bed, or a combination of both effects (Johnson et al, 1971)

3.2 - SALWA MEMBER (General) 1) Consists of heterolithic siliciclastic-calcareous sediments which were laid down under meso-tomicrotidal conditions (Dill et al, 2005). 2) Stromatolites are not present in this member (LeBlanc; this publication). 3) In Khashm Al-Nakhsh, it is composed mainly of shale, marl, limestone and some sand intercalations with echinoids, pelecypods and abundant burrows. (LeBlanc; this publication). 4) In Kharrarah, it is composed mainly of limestone and marl with some small sized echinoids and crabs. The thickness is 21 metres (Hewaidy, 1991) (Fig. 3.6) 5) the [Salwa] Member was deposited in warm (25°-30°C), clear, shallow water within the inner neritic zone (0-35 m deep) with salinity levels from 35 to 50 ppt (Al-Saad et al, 2002a). 6) Some of the beds are particularly fossiliferous, one of the most noticeable being a thin bed of limestone crowded with a species of oyster [Ostrea latimarginata & Placuna Placenta]. This bed can be seen towards the top of the formation on the road from Karanah to Umm Bab where it crosses the southern edge of Ti's Karanah. (Seltrust (1980)) 7) Another feature of the formation is the sporadic occurrence of fossilised vertebrate bones (Seltrust (1980)). 8) The clayey facies, often greenish or reddish in colour, which is predominant in the southwest tends to be substituted in part eastwards by whitish clayey limestones. The clay beds reach 4 - 5 metres in thickness, and can best be observed in the [QNCC sand] quarry at Wadi al Huwaylah south of Umm Bab, where they are extracted for use in cement manufacture. (Seltrust (1980)) http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar 9) Fossils are numerous in these predominantly marine beds and include molluscs (Clementia papyracea, Cardium, Cardita, Conus, Turritella, Anomia, Ostrea latimarginata, Pectinidae, Cypraea, Natica). Corals, echinoderms [Fibularia], Foraminifera and Bryozoa have also been recorded, together with crabs and shark and reptile teeth and bones (Seltrust (1980)) 10) The largest number of radiometric anomalies in Qatar (45%) are associated with marly and phosphatic limestones of the Lower Dam Formation [Salwa Member], but none of them has significant radioactivity. The cause of radioactive anomalies recorded in the Lower Dam limestones is mostly the presence of some vertebrate remains (bones, teeth and coprolites) rich in phosphate. (El-Kassas, 1992) 3.2.1 - Lower Salwa 1) The Lower Salwa is a silicate-dolomite-calcite sequence. The base is a deeper marine environment (Fine-grained siliciclastics) while the top stratum (Calcitic clay-rich marlstone) is an inter-tidal to beach environment (Dill et al, 2005 & 2007). 2) The ichnofossil assemblage is characterized by straight and branched burrows in sediment composed of Cardita debris. Trace fossils are ubiquitous in lithofacies association I. The organisms burrowed their shaft and tunnels in a low to moderate energy regime. These crawling and grazing feeding trails were described from less turbulent waters (restricted) carbonate platforms at water depths between 5 and 25 m (Dill et al, 2005). 3) Horizontal stratification with even bedding planes and bedsets measuring up to 1 m is widespread particularly in the siltstones and fine grained sandstones of the Lower and Upper Salwa Members (Dill et al, 2005). 4) Rock colors with bright gray and brownish tints indicate well-oxygenated conditions (Dill et al, 2005). 5) According to Cavelier (1970), a sandstone unit in the Dam Formation was said to contain “Mammal bones & teeth” . (Whybrow, 1987a) 3.2.2 - Middle Salwa 1) Some fine-grained siliciclastics in this Salwa lithofacies associations developed planar cross stratification. The ripple-laminated beset suggest a rather low water level and well-oxygenated bathymetric conditions. The ripples in the bedsets are akin to herringbone cross-lamination and common to tidal environments (Dill et al, 2005). 2) Most likely the environment was the distal part of a tidal delta complex (Salwa 4) while a lagoonal environment prevailed in Salwa 2 & 3 (fig 3.12a&b). The water depth reached a maximum in the Salwa 2 and Salwa 3 (approximately 20 m) (Dill et al, 2005). 3) Bonebeds full of shark teeth, locally, containing also invertebrate fossil hash came into being at the base of the cyclothems (Dill et al, 2005). 4) Impressive quantity of the echinoderm Fibularia damensis are found in white (chalk) limestone beds (LeBlanc, this publication) (see Chapter 4.2.2). Cavelier (1970) and Whybrow (1987a) call this limestone the “button-bed”. 5) Part of the Middle Salwa has also been interpreted as a restricted platform sedimentary unit. The top strata, however, are interpreted as a beachrock (intertidal environment) very much like the lithologies in the Lower Salwa (Dill et al, 2007). 6) Red and green rock colors observed in this sub-member indicate varying oxidising and reducing conditions. The basin began deepening during the passage into the Middle Salwa Member. The state of oxygenation deteriorated (dysaerobic reducing conditions), so that part of the environment is described as lagoonal (Dill et al, 2005). 7) From the sequence stratigraphic point of view, the maximum flooding surface is likely to lie within the Middle Salwa Member (Dill et al, 2005).

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Fossils of the Miocene Dam Formation of Qatar 3.2.3 - Upper Salwa 1) Horizontal stratification with even bedding planes and bedsets measuring up to 1 m is widespread particularly in the siltstones and fine grained sandstones of the Lower and Upper Salwa Members (Dill et al, 2005). 2) Some fine-grained siliciclastics of the Salwa lithofacies associations developed planar cross stratification (Dill et al, 2005). 3) Red [shale] beds are particularly widespread in the Upper Salwa, locally alternating with dark gray and green [shale] beds (Dill et al, 2005). 4) The red and green shale beds are by far the most reliable marker which occurs at the top of the marly sequence [base of Upper Salwa]. This marker is clearly seen at the base of the ridge on the coast side, about 10 to 12 feet thick [about 3.5m] in most areas underlying a chalky bed five or more feet thick [1.5m]. On the east side of the ridge the shale outcrop is less clearly seen and the thickness of the shale sequence appears to be less (Johnson et al, 1971) 5) Ostrea, known to be widespread in estuaries and tidal flats, paves the way from the subtidal environment of the Salwa Members into the inter- to supratidal subenvironments of the Al Nakhsh Members. The fauna that created the ichnofossils had their habitat in the subtidal to lower intertidal or shoreface environments (Dill et al, 2005). 6) An extensive bed of Ostrea Latimarginata and Placuna sp. occurs at the base of a green shale (Johnson et al, 1971)

3.3 - AL-NAKHSH MEMBER (General) 1) Formed under macrotidal conditions with sub-to-supratidal depositional environments passing into continental ones. Celestite, gypsum, and microbial mats (stromatolites) are very widespread in these sabkha sediments. Crystals of gypsum and the thickness of stromatolites tremendously increase towards younger sediments indicating thereby a close genetic link between growth of microbial domes and gypsum precipitation (Dill et al, 2005) 2) Thirty-three (33) metres thick in Khashm Al-Nakhsh (Dill et al, 2005) 3) This member is the only one with Stromatolite occurrences (LeBlanc; this publication). 4) Stromatolites evolve from centimeter-thick LLH stromatolites in the lower part to giant SH stromatolites in the upper part of the Al Nakhsh Member. (Dill et al, 2005). 5) It shows cyclic sedimentation (Puls et al, 2008) 6) In Khashm Al- Nakhsh, it is composed of limestone, marl, stromatolitic limestone and evaporites (LeBlanc; this publication). 7) The stromatolites are frequent and concentrated in certain horizons and the evaporites consist mainly of gypsum towards the base and of celestite towards the top. Some limestone horizons are rich in mollusc shells and casts. (Hewaidy, 1991). 8) In Kharrarah, it is mainly composed of limestone and some evaporite intercalations (celestite). No stromatolites are recorded. (Hewaidy, 1991). (Fig. 3.6) 9) The environment of deposition is transitional between normal marine and hypersaline evaporitic conditions. Corbula, Cardita, and the Cerithidae seemed to be very tolerant as to such very inhospitable conditions (Dill et al, 2005). 10) A warm littoral to sabkha (hypersaline) environments of deposition (Al-Saad et al, 2002a) 11) Clay facies, which are quite prominent in the Abu Samrah area, tend to be replaced by a carbonate facies [more to the north] which accompanies the change from marine to lagoonal conditions (Seltrust (1980)) 12) A wide variety of fossils occur [in the Al-Nakhsh] reflecting the more varied environment. These include molluscs (Ostrea latimarginata, Chamis senatoria, Clausinella persica, Hydrobia, Natica, Lucina, Capsa lacunosa, Tellina biparta, Cardiocardita, Cerithidae, Cardium, Lima, Modiola), echinoderms [Fibularia], diplodonts, Bryozoa, crabs, sharks teeth and Foraminifera (Seltrust (1980)). http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar 13) A cyclic succession of clay, marl, chalk, limestone and gypsum was deposited - the gypsum (now recrystallised) varying from massive 2 metre thick beds to thin nodular horizons. Further north and at Kharaij, Ti's Karanah, Al Huriyah and Huraythi, thin beds and nodules of strontium sulphate (celestite) occur commonly associated with a thin variegated green to red clay horizon at the base of the Upper Dam [base of Upper Salwa?]. It would appear from their mapped distribution that the gypsum and celestite - were formed under differing circumstances since in general they do not occur in the same locality (Seltrust (1980)). 3.3.1 - Lower Al-Nakhsh 1) At 48 m (fig 3.12a&b), LLH stromatolites appear in the Lower Al Nakhsh with tepee structures and centimeter-thick laminae. At 50 m, patches of columnar microbial structures (SH), covering several hundreds of square meters developed on top of LLH stromatolites. The individual columns form a sort of a stromatolite pavement. Tidal channels are indicated in the sedimentary record by the bioclastic pure limestones in the lower section of each cycles (subtidal) (Dill et al, 2005). 2) There is one type of stromatolite which does not fit well in this pattern of LLH and SH microbial/stromatolitic structures (Fig. 4.3.4a). This stromatolite extends horizontally across several square meters and is akin to the LLH stromatolites. Some concentric ring structures are randomly distributed among an irregularly-shaped network. In places, these rings have a central knob or a column erected like a broken tree trunk. These were interpreted in terms of microbial mat blisters and gas escape structures. The ring structures in an overall network are produced by degassing processes. The microbial mats are expanded to form mat blisters. After the leathery skin of the mat is being destroyed by the gas overpressure the structure collapses and the circular remains get preserved. These biogenic decay structures are held to be indicative of a rather low rate of sedimentation. Otherwise such delicate structures would have not been preserved (Dill et al, 2005). 3.3.2 - Middle Al-Nakhsh 1) The clay and siltstones are rich in [anhydrite] nodules (Dill et al, 2005). 2) The climax of stromatolites growth is reached in the Middle Al Nakhsh with as much as 2 m in diameter and 0.5 m in height (Fig 4.3.4f). The maximum size of stromatolites (SH) is achieved in beds immediately underneath the boundary between the Middle and Upper Al Nakhsh Member, where domal structures measuring 2 m across cover a wide platform [as mapped by the author]. Internally, these domal structures (or thrombolite buildups–microbial mounds) consist of a dense irregularly-shaped network (Dill et al, 2005). 7) Transitional types between SH and LLH stromatolites occur [at the base of the Middle AlNakhsh]. Their internal structure closely resembles that of oncoids exfoliating in an onion-shell style (figs 4.3.4d & e) (Dill et al, 2005). 3.3.3 - Upper Al-Nakhsh 1) The Upper Al-Nakhsh is brown and red in colour with thick gypsum seam. Celestite and Bassanite also occur (Dill et al, 2005). 2) There are no burrows or textures which might indicate that fauna was responsible for the bioturbation (Dill et al, 2005). 3) It is the most landward (inland sabkha) equivalent of the Al-Nakhsh (Dill et al, 2005). 4) Mega cross-bedding in the Upper Al-Nakhsh, with foresets dipping at an angle of 27º, suggests that these clastic sediments are of aeolian origin (Fig 3.1 and Chapter 6.3) (Dill et al, 2005). 5) The red bed facies in the Upper Al-Nakhsh with gypsum-bearing coarsening-upward cycle represents the maximum regression following the supratidal regime of the Middle A1-Nakhsh.

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Fossils of the Miocene Dam Formation of Qatar It passes into mottled argillaceous calcrete, which evolved on top of shoals in the sabkha or may grade into arenaceous aeolian deposits (Dill et al, 2005). 6) The beds of massive gypsum are only locally present as one moves northwards along the scarp from [Khashm Al-Nakhsh]; also these beds seem to show some of the strongest anomalous dips (Johnson et al, 1971)

Fig 3.1: How the Khashm Al-Nakhsh (area 1) could have looked like at the close of the Al Nakhsh member deposition. (modified from Al Bowardi et al. 2005)

3.4 - ABU SAMRAH 1) The marine calcareous sediments were deposited in a microtidal wave-dominated environment. Dissolution of Eocene evaporites at depth governed the lithofacies differentiation in the Miocene Dam Formation” (Dill et al. 2005). 2) Eight (8) metres thick in Khashm Al-Nakhsh (Dill et al, 2005) 3) Irregular burrows occur and a shell bed marks the boundary between the Abu Samrah and AlNakhsh Members. This fossiliferous layer is contained in a thinly bedded sequence of calcareous and siliciclastic rocks (Dill et al, 2005). 4) There are no vertebrate remains [except for shark teeth] (Dill et al, 2005). 5) A great variety of cross-bedding types attest to fluctuating energy regimes (Dill et al, 2005). 6) In the Abu Samrah Member the marine setting has almost completely turned from a tidedominated into wave-dominated beach environment (Dill et al, 2005). 7) Hydrobia is a snail that needs a wet habitat to be active either covered by seawater or by moving in fluid layers for low-tide conditions. Not surprisingly, these gastropods appear in a great number in the Abu Samrah Member as the supratidal/continental environment of the Upper AlNakhsh became re-inundated (Dill et al, 2005). http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar 8) The calcareous beds immediately beneath the unconformity, which is overlain by fluvial gravely sediments of the Pliocene Hofuf Formation, were named beach rocks (Dill et al, 2007). 9) Thin ripple marked sandstones have been observed near the top in the An Nafkhah - Qarn Abu Wail area indicating a coastal depositional environment (Seltrust (1980))

Fig 3.2 : Two cross-sections of approximate “A – B” transect location in fig. 2.4 (top - Puls et al 2008; bottom - Seltrust, 1980)

Figure 3.3: The Dam Formation exposed on “Khashm al Nakhsh” along Salwa Road in SW Qatar (Area 1).

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.4: Location of the three schematic sections drawn by Johnson et al, 1971, as illustrated in fig. 3.5 below, together with our corresponding areas 1, 5 and 7

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.5: Schematic cross-sections of the Dam Formation at three localities in western Qatar (fig 3.4) (modified from Johnson et al, 1971)

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.6: Al Kharrarah section (Area 4) compared with Al Nakhsh and nearby sections (area 1).(modified from Hewaidy (1991) and Al Saad (2002a)) http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar

The five figures (3.7 to 3.11) below are composites of Cavelier (1970) and Dill et al’s (2007) subdivisions of the Dam Formation at two geographical locations while figure 3.12 show Dill et al’s (2007) original stratigraphic column over Khashm Al-Nakhsh.

Fig 3.7: Lithology and color code legend used in the composite figures 3.8 to 3.11 below (Cavelier, 1970; colors established by the author) http://leblanc.jacques.googlepages.com/fossilhome

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.8: Composite Stratigraphic column on the eastern flank of Hazm Mishabiyah (see appendix “Glossary & Coordinates”) showing the Upper Dam Formation of Cavelier (1970) and the subdivisions of the Al-Nakhsh member by Dill et al. (2007)

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.9: Composite Stratigraphic column of the Southern flank of the hill (24.687492°N and 50.865029°E) located 1.5 kms NNE of Qarn Abu Wail showing the Upper Dam Formation of Cavelier (1970) and the subdivisions of the Abu Samrah & Al-Nakhsh members by Dill et al. (2007)

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.10: Composite Stratigraphic column on the eastern flank of Hazm Mishabiyah (see appendix “Glossary & Coordinates”) showing the Lower Dam Formation of Cavelier (1970) and the subdivisions of the Salwa member by Dill et al. (2007)

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Fossils of the Miocene Dam Formation of Qatar

Fig 3.11: Composite Stratigraphic column of the Southern flank of the hill (24.687492°N and 50.865029°E) located 1.5 kms NNE of Qarn Abu Wail showing the Lower Dam Formation of Cavelier (1970) and the subdivisions of the Salwa member by Dill et al. (2007)

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Fossils of the Miocene Dam Formation of Qatar

Fig. 3.12a: Litholog of the Miocene Dam Formation and its depositional environments. All depth-related data are given in metres, all dimensions in the litholog are given in centimetres (Dill et al. 2007). See also our poster 30 http://leblanc.jacques.googlepages.com/fossilhome

Fossils of the Miocene Dam Formation of Qatar

Fig. 3.12b (Continued from previous page). See also our poster http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation)

4.0 The macrofossils of the Dam Formations in Qatar Table 4.1 below summarizes the fossil content of the Dam formation. Each fossil type is discussed in more details in the sub-chapters that follow.

Table 4.1: Macrofossils of the Dam Formation in Qatar Subphylum/Class

Name / Note

Fossil Type

Type Locality

4.1 - Vertebrates 4.1.1 – Pisces / Fish

4.1.2 - Mammals

Sharks

Teeth

A3_2023

Rays (Aetobatus?)

Pavement teeth

A1_4038

Teleosts (Diodon and unidentified) Sirenia (Dugong)

Tooth plates and Vertebrae Ribs & vertebrae Teeth and other parts

??

4.1.3 - Reptiles 4.2 – Marine Invertebrates 4.2.1a – Leucosiidae (crabs) 4.2.1 - Arthropods 4.2.1b Callianassidae (mud shrimp) 4.2.2 – Echinoderms / Sea Urchins

4.2.3 Corals / Scleractinia 4.2.4 - Bryozoa

4.2.5 - Mollusks

4.2.5a – Bivalvia

Typilobus/Leucosia xanthoids, portunoids and callapids

claw, carapace

A3_4001 A3_2040 A1_2115, A3_1019 N/A N/A

Claws

A1_4009

Callianassa

claw, carapace

A3_2035

Goniocidaris noellingi Agassizia persica Fibularia damensis Opechinus costatus Common in the Lower Salwa Steginoporella Phidoloporidae (or Sertella) Anadara Anomiidae Barbatia Capsa

Spines shell or "test" shell or "test" shell or "test"

N/A A1_4016 A1_2010 A3_4010

Shell Shell Shell Shell

Cardiidae

Shell

Carditidae

Shell

Chlamys Clausinella persica Clementia senatoria (veneridae) Corbicula sp. Corbula sp. Diplodonta Limidae Lucina Mactridae Mytilidae

Shell Shell

Shell Shell Shell Shell Shell Shell Shell

Ostrea latimarginata

Shell

Pectinidae Placuna Tellina

Shell Shell Shell

Colonial Corals

A1_1077 & 1078 N/A A3_2035

Shell

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N/A N/A N/A N/A Lower Salwa, Abu Samrah Lower Salwa, Middle Al-Nakhsh N/A Abu Samrah Lower Salwa, Middle Al-Nakhsh N/A Middle Al-Nakhsh N/A Lower Al-Nakh N/A N/A Lower Al-Nakhsh A1_3028 & Lower Al-Nakhsh Upper Salwa A2_3001, A3_2027 N/A

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Table 4.1 (Continue): Macro Fossils of the Dam Formation in Qatar Subphylum

Class

Name / Note Acteocina Balanidae Cerithiacea

4.2.5 - Mollusks

4.2.5b -Gastropods

Cerithiidae Conidae Fissurellidae Hydrobiidae Naticidae Turritellidae Xenophoridae

Fossil Type Shell Shell Shell

Type Locality N/A N/A N/A A2_2040 & Lower Al-Nakhsh A1_1034 N/A Abu Samrah Middle Al-Nakhsh Lower Salwa Lower Salwa

Shell Shell Shell Shell Shell Shell Shell

4.3 - Miscellaneous LLH SH SS unknown

4.3.1 - Stromatolites

A2_5022 A1_4002, A1_5060 A1_5005 A1_4008

4.4 - Plants Unidentified

A3_2037

Please respect all the fossil sites that you visit or discover. Bringing back home more than necessary will be a waste. Keeping the sites clean and as intact as possible for others to enjoy should be your priority. Please do not collect or damage the vertebrate sites mentioned in this publication, especially those with fossil dugong remains; they are being studied by the Qatar Museum Authority (QMA). If you do discover more vertebrate sites, please report them either to QMA or to the author (who will forward the information to QMA).

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The Miocene Guide of Qatar, Middle East (Dam Formation)

4.1 - Vertebrates 4.1.1 – Pisces (Sharks, Rays & Teleosts) The available publications on the Dam Formation give the impression that shark teeth are plentiful in the Miocene of Qatar. Cavelier (1970) mentions them as being “fairly abundant” while ElKassas (1992) also mentions “The cause for radioactive anomalies recorded in the Lower Dam limestones is mostly the presence of some vertebrate remains (bones, teeth and coprolites) rich in phosphate”. More recently, Dill et al 2005 & 2007 place the shark teeth at different levels within their stratigraphic section over the Al-Nakhsh Hill and surrounding area. While discussing the Middle Salwa geology, the latter states “Bonebeds full of shark teeth, locally containing also invertebrate fossil hash, came into being at the base of the cyclothems”. The author, however, had very little luck in finding the bonanza of Miocene vertebrate teeth stressed in these publications over the large area of his research. The only specimens found during his one year exploration period were three shark teeth from the Middle and Upper Salwa Members (figures 4.1.1 & 4.1.2 and picture at A3_3018, however, according to Otero et al 2001 the latter could also be a Hepsetidae which is a type of Pike fish which, strangely enough, lives in freshwater), and a beautiful large toothplate (figs 4.1.3) of a Myliobatis (a type of ancient stingray) together with a smaller one (not shown) from the Lower Al-Nakhsh Member.

Fig 4.1.1: Shark tooth. (A1_2118)

Fig 4.1.2: Shark tooth (Galeocerdo?). (A3_2023)

Fig 4.1.3: Front and back of specimen found at locality A1_4038. From Dr. Iyad S. Zalmout of the Museum of Paleontology at the University of Michigan: "A unique specimen of a batoidae lower jaw (Pavement Teeth in Articulation). I think it is myliobatid Jaw". From Dr. Friedrich Pfeil: "that´s an almost complete toothplate of a Myliobatis sp. - a very nice one! With 135 named species of which 78 could be valid names, it is impossible to give a correct species name, not at the moment. However, this is an important specimen for later determination.". http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Miocene Myliobatis toothplate drawings

Fig 4.1.4:

Fig 4.1.5:

1a) Oral surface of lower dental pavement, somewhat worn, and showing line of 1a) Oral surface of the upper dental pavement of an adult longitudinal striae or fissures of the gano- individual, the anterior end (shown uppermost in the figure) dentine radiating backwards and outwards. fractured and imperfect. 1b) Transverse view of the same specimen at 1b) Transverse view of the same specimen, taken across its its posterior end (across the bottom of drawing posterior end (at bottom of drawing 1a) la) 2a) Oral surface of imperfect lower dental pavement, the anterior end shown uppermost. 2b) Transverse view of the same specimen. 3) Oral surface of imperfect lower dental pavement, somewhat worn, and showing curved outline of the anterior depression due to wear. 4) Portion of large caudal spine of an eagle or sting-ray.

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The Miocene Guide of Qatar, Middle East (Dam Formation) Teleostei (such as Trouts, Salmons, Groupers and Barracuda) is one of three infraclasses in class Actinopterygii, the ray-finned fishes. This diverse group, which arose in the Triassic period includes 20,000 extant species in about 40 orders; most living fishes are members of this group. The other two infraclasses are Holostei and Chondrostei. In earlier publications, teleosts from the Dam were always described as “undetermined” (Fig 4.1.6b). The author, however was able to identify with more accuracy one genus from this infraclass of fish. Species of the genus “diodon” (fig 4.1.6a) are usually known as porcupinefishes or balloonfishes. Fish of this genus have two-rooted, moveable spines (actually modified scales) distributed over their bodies and beak-like jaws, used to crush their hard-shelled prey (crustaceans and molluscs)

Fig 4.1.6a: Fish in the genus Diodon can inflate themselves (bottom; www.wikipedia.org ), making their spines stand perpendicular to the skin. When inflated they pose a major difficulty to their predators: a large diodon fully inflated can choke a shark to death. The material that was found in the Dam Formation (as shown above; A3_4001) consists of two relatively thin trituration/masticatory tooth plates each formed by a series of four or five slightly convex plates, most of which are well exposed along the trituration surface. (Drawing from Otero et al (2001))

Fig 4.1.6b: Vertebrae of unidentified teleosts (A3_2040)

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The Miocene Guide of Qatar, Middle East (Dam Formation)

4.1.2 – Mammals (Sirenians/Dugongs) The modern dugong (Dugong dugon) is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the oncediverse family Dugongidae; its closest modern relative, Steller's Sea Cow (Hydrodamalis gigas) was hunted to extinction in the 18th century. It is also the only sirenian in its range, which spans the waters of at least 37 countries throughout the Indo-Pacific, though the majority of dugongs live in the northern waters of Australia between Shark Bay and Moreton Bay. In addition, the dugong is the only strictly-marine herbivorous mammal, as all species of manatee utilize fresh water to some degree. Like all modern sirenians, the dugong (fig 4.1.7) has a fusiform body with no dorsal fin or hindlimbs, instead possessing paddle-like forelimbs used to maneuver itself. It is easily distinguished from the manatees by its fluked, dolphin-like tail, but also possesses a unique skull and teeth. The dugong is heavily dependent on seagrasses for subsistence and is thus restricted to the coastal habitats where they grow, with the largest dugong concentrations typically occurring in wide, shallow, protected areas such as bays, mangrove channels and the lee sides of large inshore islands. Its snout is sharply downturned, an adaptation for grazing and uprooting benthic seagrasses. The IUCN lists the dugong as a species vulnerable to extinction (source www.wikipedia.org )

Fig 4.1.7: Physiognomy of dugongs and manatees

It has been much easier for the author to find dugong remains in the Dam Formation than it has been for sharks. These have been found in the Lower Al-Nakhsh sub-member and at all the levels within the Salwa Member. In total, seventy-one (71) sites have been discovered so far; some of which deserving to be protected and preserved (A1_1029 and the whole sectors around A1_2115 and A3-1015 are good examples). The main body parts found are ribs and vertebrae, however one skull part could be determined (Fig 4.1.17) Miocene dugong remains in Qatar were known previously in the literature (Whybrow, 1987a) however there did not seem to be an accurate cataloguing of their localities by any institution incountry or abroad. I hope that this publication will change all this. The author also believes that some dugong bones were misinterpreted as being reptile bones by earlier authors. NOTE: On June 14th 2009, the author handed-over all the Miocene & Eocene dugong bones in his possession to the Qatar Museums Authority (http://www.qma.com.qa/eng/ ) which had been designated earlier during the year by the government as the official Qatari institution to catalogue and preserve the paleontological remains found in the country (together with conducting its normal archeological duties) http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig 4.1.8: A1_1029. At least seven dugong ribs and two vertebrae on a mound of a yellowish limestone

Fig 4.1.9: A1_2112. The first dugong rib locality found by the author

Fig 4.1.10: A1_2115. A large rib and two vertebrae.

Fig 4.1.11: A1_2119. Proximal rib of some heavy weight sea cow in a white limestone

Fig 4.1.12: A1_3035. Very brittle ribs laying in the green shale at the base of the Upper Salwa Member.

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Fig 4.1.13: A1_3065. Broken bones and one vertebra

Fig 4.1.14: A1_4018. “It looks like a sternal element, and could be a xephisternum (the wider edge is the proximal end towards the skull, the Fig 4.1.15: A1_4019. Several broken-up bones broken side is distal or toward the tail, and the including a possible skull fragment (top right). side with slight keel is ventral); This is too flat (pers. Comm.., Dr. Zalmout) for a Protosiren, and may fit with Eotheroides or Eosiren sternal morphology” (Dr. Zalmout)

Fig. 4.1.16: A1_4138. One vertebra

Fig 4.1.17: A1_4039. "Palatal view of right posterior corner of a sea cow skull, exactly at the squamosal, part of the pterygoid and part of the palatine." (Identified by Dr. Zalmout)

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Fig 4.1.18: An important sector was discovered by the author within Area 3. Over 47 localities of fossil dugong remains ribs and vertebrae were found in the Lower Salwa together with one locality in the Middle Salwa. Note: The shark tooth shown in figure 4.1.2 above was found in locality 2023 together with dugong remains

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4.1.3 – Reptiles Cavelier (1970) mentions the occurrence of reptile teeth and other reptile remains (together with shark teeth) in his Lower Dam Member, which would place it somewhere in the Lower or Middle Salwa. Unfortunately, our investigation did not reveal any of these. While the author does not deny the possibility of finding fossil reptiles in the Dam formation, he believes that several “reptile remains” reported in earlier documents were wrongly interpreted. It is believe that several of these remains belonged to those of sirenia/dugongs.

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4.2 – Marine Invertebrates The term "marine invertebrates" is used to describe animals found in a marine environment which are invertebrates: lacking a notochord. In order to protect themselves, they may have evolved a shell or a hard exoskeleton, but this is not always the case. As on land, invertebrates make up a huge portion of all life in the sea; a small portion are found in the Dam Formation and are discussed below:

4.2.1 – Arthropods An arthropod is an invertebrate that has an exoskeleton (external skeleton), a segmented body, and jointed attachments called appendages. Among others, they include the insects, arachnids, and crustaceans (crabs & shrimps). 4.2.1a – Leucosiidae (Crabs) Crabs (figs 4.2.2 & 4.2.3) are but a small picture of the overall diversity of the Crustacea. They represent only one infraorder [Brachyura] within one order [Decapoda] within one superorder [Eucarida] within one subclass [Eumalacostraca] within one class [Malacostraca] of the six currently recognized classes of the Crustacea (Fig. 4.2.1) Most Decapoda are marine, some are found in brackish water, few live in fresh water, and only some, such as some Brachyura (crabs), are adapted to life on land. The text that follows will discuss only those fossil crabs that lived in the marine environment since it is obvious that the sediments of the Miocene Dam Formation (especially the Middle Salwa in which they strived) are of this type Fossil crabs of the World (Marine environment) Crabs are common in Tertiary and Upper Cretaceous shallow-water deposits, but their usually fragmental remains rarely attract attention. Crabs living on rocky shores have little chance of preservation. Grapsidae, which are common today, are rare fossils probably for this reason. Crabs living on soft sand and clay and others adapted to coral reefs are more common, while burrowers in shifting sands of the tidal zone are rare or entirely unknown as fossils (e.g., Hippoidea). Other burrowers are distinctly favored in preservation, with the result that the picture of fossil littoral and sublittoral communities is biased. A distinctive fauna lives today in the phytal, in algal and other marine plant growths; fossil Oxyrhyncha (a type of crab) may indicate this environment. Others live on muddy ground below wave base. Paguroidea (hermit crab [not a true crab]), which also have strongly calcified claws, are fairly common in shallow water sediments from Jurassic to Recent. They are known not only as skeletal remains (chelae and fingers) but also from their effect on molluscan shells. Crabs are also found in reef limestones. In the Eocene the fauna of similar habitats is more modern, and in the Miocene it is close to the present Indopacific fauna, with Daira and other xanthoids dominant, associated with Calappa (all crabs). As can be expected, the thin-shelled Trapeziidae (crab), Caridea (shrimp), and Stenopodidea (shrimp), which are common among coral reefs today, are not preserved in this environment. An entirely different association is found in calcareous shales and thin-bedded limestones. Most of them are rich in fish remains. These shales contain benthonic macrurans (crabs, lobsters, crayfishes, shrimps, and prawns) with short legs, associated with nectonic macrurans, which have long legs.

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The Miocene Guide of Qatar, Middle East (Dam Formation) Stratigraphic Distribution In the Tertiary a gradual approach to the modern fauna is found, with a rapid advance in numbers and diversification of crabs corresponding to a reduction in reptant macrurans. Recent Indopacific genera and families are widespread in mid-Tertiary sediments, because of the warmer climate of this period. The primitive Dromiacea and Kaninidae, however, showed a remarkable reduction during this period, while the Oxyrhyncha appeared for the first time and flourished. The Xanthidae became widespread and varied but their Early Tertiary genera differed significantly from the Late Tertiary representatives, and many Late Tertiary crabs have survived to the present. Callianassa (see Chapter 4.3.1b on “mud shrimps”) chelae are almost ubiquitous in Tertiary sediments. "Crabbeds" filled with carapaces of Xanthopsis or Harpactocarcinus and other similar genera are widespread in Lower Tertiary warm-water deposits.

Fig 4.2.1: Classification of the crabs (Martin et al. 2001). More information can be seen on http://decapoda.free.fr/search_data.php http://leblanc.jacques.googlepages.com/fossilhome

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Fig 4.2.2: Crabs are characterized by a broad flattened cephalothorax covered by a hard carapace with a small abdomen concealed beneath it, short antennae, and five pairs of legs, of which the anterior pair are large and pincerlike.

Fig 4.2.3: Technical terms and measurements http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) Fossil Crabs of the Dam Formation The fossil crabs of the Dam Formation belong to the Leucosiidae (fig 4.2.4) Family and Xanthoid, Portunoid and Calappid (fig 4.2.14) Superfamilies. They are found at different levels but most commonly in the Middle Salwa and Lower Al-Nakhsh together with the Callianassa (mud shrimp) also described in this publication The Leucosiidae are also known as “Pebble crabs”. Those living today hide in small pools, along stream banks, in mud-sand, broken-shell and coral bottoms. They live in shallow waters to a depth of 160m. They are slow-moving and hide under soft mud during the day. As such, they are rarely seen. They feed on small animals in the muds.

Animalia Arthropoda Malacostraca Decapoda Leucosioidea Leucosiidae Acanthilia Actaeomorpha Callidactylus Ebalia Heteronucia Iliacantha Leucosia Lithadia Myra Myropsis Nucia Oreotlos Persephona Randallia Speloeophorus Uhlias

Fig 4.2.4: The various genus belonging to the Family Leucosiidae (left) and several species of modern Leucosia (right). From Galil (2006).

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The Miocene Guide of Qatar, Middle East (Dam Formation) 4.2.1b - Callianassidae (Mud Shrimps) “The claws [figs 4.2.11 and 4.2.12] look like Callianassa-type claws [mud shrimps], of two different types. Beyond that, it is not really possible to determine the genus and species. Callianassid claws are often quite common decapod elements, and they may or may not be associated with other types of decapods.” (April 8th 2009; Personal communication; Dr. Carrie E. Schweitzer, Department of Geology, Kent State University, Ohio) Subphylum: Class: Subclass: Superorder: Order: Suborder: Infraorder: Superfamily: Family: Subfamily: Genus:

Crustacea Malacostraca Eumalacostraca Eucarida Decapoda Pleocyemata Thalassinidea Callianassoidea Callianassidae Callianassinae Callianassa

Callianassa, which is also mentioned by Whybrow (1987a), belongs to the infraorder of the Thalassinidea (decapod crustaceans) that live in burrows in muddy bottoms of the world's oceans. They have few vernacular names such as "mud lobster/shrimp" and "ghost shrimp". Callianassa creates complex burrow systems in mud sediments from the lower shore to the shallow sublittoral. The burrows (figs 4.2.9, 4.2.10 & 4.2.13), which have been recorded up to 81 cm deep, consist of a multi-branched network of tunnels connected to several inhalant shafts, each terminating in a funnel shaped opening to the surface. Recent molecular analyses have shown that Thalassinidea is most closely related to Brachyura (crabs) and Anomura (hermit crabs and their allies). The fossil record of thalassinideans reaches back to the late Jurassic. There are believed to be 556 extant species of thalassinideans in 96 genera, with the greatest diversity in the tropics, although with some species reaching latitudes above 60° north. About 95% of species live in shallow water (Some Callianassa even live in mudflats and muddy sand beaches at low tide level) with only three taxa living below 2000 m. A modern mud shrimp (Callianassa filholi) lives in a permanent burrow (fig 4.2.9) including turning chambers, side rooms for storing feces and pieces of shell, with multiple entrances and an exit at the top of a low mound. A male and a female normally occupy a burrow. The large hairy first legs and the smaller second pair form a sieve used to strain detritus food from the water current created by the swimming limbs on the underside of the abdomen. When feeding the shrimp moves close to one of the entrances. The nippers have the shape normal for a crab or shrimp and in the male one of them (right or left) is very large. The female has an enlarged second abdominal segment. Digging is done with the first, second and third pairs of walking limbs and the spoil is carried to an entrance held in the last pair of mouth appendages. Adult length is up to 60 mm. They are transparent and colourless, except for tinges of vermilion.

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig 4.2.5: Several body parts of Callianassa subterranean . Nguyen (2003)

Fig 4.2.6: Callianassa californiensis (wikipedia)

Fig 4.2.7: Callianassa tyrrhena . (wikipedia)

Fig 4.2.8: Callianassa tyrrhena (wikipedia)

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig 4.2.9: Shrimp burrows. Example from the Miocene of Spain. Seilacher (2007)

Fig 4.2.10: Mud shrimp Trace fossils in limestone; seen after a rain, A1_5093. See also Fig 4.2.13

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Dam Formation mud shrimps (Callianassa)

Fig 4.2.11: Complete mud shrimp claw (A3_2035)

Fig 4.2.13: 3D burrow remain of a mud shrimp later cemented by iron oxides, including hematite. Organic matter related to the burrow organisms provides a locally reducing environment that mobilizes the iron. Iron is precipitated at the interface upon contact with oxidizing water. (A3_2035). (see also chapter 4.2.3 on corals)

Fig 4.2.12: Partial mud shrimp claw (A3_2036)

Fig 4.2.14: (A1_4009). Communication dated May 18th 2009 with Dr. Carrie E. Schweitzer: “The plate of multiple claws has several taxa. The ones with entire mani, i.e., the three closest to the ruler and the three above them are callianassids [mud shrimp]. The isolated fingers, however, are a mixture. The one at the very top (opposite the ruler) looks xanthoid [crab] or portunoid, [crab] based upon the large molariform teeth on the occlusal surface. There is one in the middle with a large tooth on the proximal end, which could be calappid [crab] The others could be callianassid. Of course, all of these could be typical of a tropical environment!”

Note: How to differentiate between mud shrimps (callianassidae) and Leucosiidae (Pebble crabs) claws: Communication dated May 18th 2009 with Dr. Carrie E. Schweitzer: “Callianassid claws are more

rectangular than leucosiid claws, which themselves are bulbous and if you look at the proximal margin, it is quite sinuous in the leucosiid. This is not the case in the callianassid. The fingers in the leucosiids are "spindly" which we don't see in callianassids either” http://leblanc.jacques.googlepages.com/fossilhome

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4.2.2 – Echinoderms (Sea urchins) Echinoderms are a phylum of marine animals found at every ocean depth, from the intertidal zone to the abyssal zone. They appeared near the start of the Cambrian period and have no freshwater or terrestrial representatives. Starfish, Brittle stars, crinoids, Sea urchins and Sand dollars all fall under this phylum The Echinoderms are important both biologically and geologically: biologically because few other groupings are so abundant in the biotic desert of the deep sea, as well as the shallower oceans, and geologically as their ossified skeletons are major contributors to many limestone, such as the ones in the Dam Formation, and can provide valuable clues as to the geological environment. The echinoderms of the Dam Formation (fig. 4.2.17) are fossilized Sea urchins (fig. 4.2.15) belonging to four species of which the following two are the most common: one is the small (1 cm in diameter) Fibularia damensis (Figs 4.2.16 & 4.2.21) found in the Middle Salwa Member in association with mud shrimps (Chapter 4.2.1b) and shell fragments, and the second is the larger (1-2 cm in diameter) Opechinus costatus species found normally in the Lower Al-Nakhsh Member (Figs 4.2.18 & 4.2.26). In both cases their shell, or "test", is round and, as per their living counterpart, it was also spiny, but these spines can very rarely be found in the Dam limestones in which they were buried. Fig. 4.2.16 shows a picture of a living "Echinocyamus" which is the most likely look alike of Fibularia Damensis. The limestone bed in which “Fibularia damensis” is found in the Dam formation is commonly called the “Button-bed” because of the huge quantity of these echinoderms that are found in it. Paleontological studies conducted around the world in sediments dating to Burdigalian tell us that after the sudden drop of temperature in the Lower Oligocene, the global temperature began to increase. The Burdigalian had a warm climate and the temperature increased even further in the upper Burdigalian, in which the Middle Salwa member belongs.

Fig 4.2.15: Drawings showing different views and shapes of Sea urchins

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Fig 4.2.16: Comparing a living Echinocyamus pusillus (1) with a Miocene Fibularia Damensis (2 to 10) From Kier (1972) and http://www.habitas.org.uk/marinelife/species.asp?item=ZB3880

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Fig 4.2.17: The echinoderms of the Dam Formation (Roman J., 1976) 1 – 12 = spines of Goniocidaris noellingi from NNE Qarn Abu Wail 13 – 15 = Agassizia persica from Qarn Abu Wail 17 – 19 = Fibularia damensis from An Nafkah 20 = Opechinus costatus from Hazm Mishabiyah

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Fig 4.2.18: Opechinus costadus Hazm Mishabiyah in Upper Dam / Lower Al-Nakhsh. (Kier, 1972)

Fig 4.2.19: Agassizia powersi (Samples 1-2). (Kier, 1972) (fig. 4.2.25)

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Fig 4.2.20: Trace fossil styles of echinoderms over time according to their environment (Seilacher, 2007). The echinoderms of the Dam formation lived in a “Shelf ” environment.

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Fig 4.2.21: Fibularia Damensis. A3_2001

Fig 4.2.22: The “button-bed” A1_2010 / A3_2001

Fig 4.2.23: Fibularia Damensis outcrop A6_1001.

Fig 4.2.24: The “button-bed” A1_2010 with shell frafment

Fig 4.2.25: Weathered Agassizia powersi A1_4016. (see fig. 4.2.19)

Fig 4.2.26: Opechinus costatus. A3_4010

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4.2.3 – Corals (Scleractinia) A common lithology of one of the limestones within the Lower Salwa sub-member is biolithite, also called “reef rock”, which represents the wave resistant core of a barrier reef (Fig 4.2.27). The occurrence of biolithe in this member attest to the lower/normal (<48ppm) salinity of the sea at this time. In comparison, today the Gulf of Salwa, west of Qatar often exceeds 50ppm.

Fig 4.2.27: Sketch describing the three parts of a reef; Biolithite – The core of the reef. Micrite – In the sheltered lagoon and in deep water offshore. Sparite – Near the reef where waves and currents rework the carbonate material By definition, a biolithite is a carbonate rock formed of organisms that grew and remained in place, comprising a rigid framework of organisms (corals, gastropods, etc..), together with associated debris. A reef represents a typical biolithite. Two types of corals found in the Lower Salwa biolithite are shown below.

Fig 4.2.28: A type of Scleractinia coral Fig 4.2.29: A type of Scleractinia coral (A1_1078) (A1_1077) Scleractinia, also called Stony corals, are exclusively marine animals; they are very similar to sea anemones but generate a hard skeleton. Much of the framework of coral reefs is formed by scleractinians. There are two groups of Scleractinia, however, the only one that builds reef are the Colonial corals found in clear and shallow tropical waters. Other good localities in the Dam formation where to find Colonial Corals and other reef-inhabiting life forms, such as gastropods, are along the ridge at A1_1034 and above the anhydrite nodule level at A4_5002 (Fig. 4.2.30) http://leblanc.jacques.googlepages.com/fossilhome

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Fig 4.2.30: Another type of Scleractinia coral (A4_5002). A very extensive horizon of such corals overlays the anhydrite nodule level; proving that the sea level rose immediately after the formation of the anhydrite nodules and making the sea deep enough for the corals to thrive.

The occurrence of oxidized bio-forms, such as burrows of mud shrimps (fig 4.2.13) and corals (Fig 4.2.31) is very common in the Dam Formation, especially in the Middle Salwa member. Sometimes, whole reef-like colonies get mineralized by colloform Fe/Mn oxide-hydroxides.

Fig 4.2.31: Ironized Reef-like sessile foraminiferal colonies (A2_2028_06 & A2_2028_4)

Fig 4.2.32: Sketch showing in profile reef-like sessile foraminiferal colonies mineralized by colloform Fe/Mn oxide-hydroxides. (Reading et al, 1982)

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4.2.4 - Bryozoa Bryozoa are colonies of tiny colonial animals called zoids and appear as gelatinous globs up to the size of a football. Bryozoa are not corals. Most species are marine animals. They are often attached to submerged surfaces such as tree branches, roots, rocks, pilings, docks, etc. Sometimes, a clump that has broken loose can be found free-floating or washed up near the shoreline. The colony consists of thousands of individual animals each living within their own tube (aperture). The living tubes are the size that a sewing needle might make. Sometimes the outer surface is covered with distinctive bumps or ridges (monticules). Colony shapes vary from delicate open mesh fronds to branching forms, massive mounds, and heavy dense fronds. Sometimes one colony will show multiple forms. Two families are found in the Dam: Phidoloporidae and Steginoporellidae More: http://www.ucmp.berkeley.edu/bryozoa/bryozoa.html or http://bryozoa.net

Fig 4.2.33: A3_2035. (Also found in the Abu Samrah member). In an email received April 9th 2009 from Dr. Paul Taylor of the Natural History Museum (UK): http://www.nhm.ac.uk/research-curation/staffdirectory/palaeontology/cv-5472.html “I can confirm that the two images you sent of possible bryozoans are indeed bryozoans. Given their age, they will be phidoloporid cheilostomes (Family Phidoloporidae), a group sometimes also called reteporids or sertellids (http://bryozoa.net/cheilostomata/phidoloporida e/index.html ). In order to identify them further it is necessary to see the fine details of their zooids, and even then generic determination can be difficult if surface preservation is not pristine.”

Fig 4.2.34: A modern Bryozoa. In the waters of Qatar today, Thalamoporella and Parasmittina, are locally abundant in the sediment. They live on the stems and fronds of brown weeds, which can be detached and float to beaches, or even far inland during periodic flooding of sabkhas. These algae can be transported to particularly remote, restricted environments such as the south of the Gulf of Salwa, where they disintegrate and deposit their encrusting Bryozoa. Articulated species seem unable to withstand salinities higher than 50 ppm; only one such species was found sporadically alive in the Gulf of Salwa. However, several living encrusting types were noted in these restricted areas.

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4.2.5 - Mollusks Other than the macrofossils already described in the previous chapters, the Dam Formation abound in several other, but not so sought after, fossils. For the present chapter, the author has compiled all the names of the fossil mollusks found in the Dam Formation by previous authors and has illustrated them with either his own collected specimens (which are few) or Recent specimens representing the closest affinity to the Miocene species . So, in no particular order, we have:

4.2.5a - Bivalves

From the Miocene Dam Formation

Fig 4.2.35 - Placuna placenta (A2_3001, A3_2027b)

Fig 4.2.36 - Ostrea Latimarginata (A type of oyster shell) (A1_3028)

Fig 4.2.37 – A Mytilidae or Modiola from the Dam (left) at A7_3020, and a Recent example (right) of Amygdalum watsoni. Mytilidae can be found from exposed rocky outer coasts to sandy bottoms. As an invader it typically requires rocky coastlines with a high rate of water flow. Most species are restricted to bays and estuaries. They normally exhibit a high salinity tolerance, being able to live in seawaters with salinities of 45 ppt to less than 10 ppt. Low seawater temperatures less than approximately 12°C appear to trigger mass mortality. http://www.discoverlife.org/mp/20q?search=M ytilus+galloprovincialis http://leblanc.jacques.googlepages.com/fossilhome

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Fig 4.2.38 – A Veneridae from the Dam (left) at A7_3020 and a modern example (right) of Clementia papyracea

Fig 4.2.39 – Tellina examples from the Dam (left) at A1_2064 and a Recent example of Tellina alternata

Modern equivalent, or from the Miocene of other localities

Fig 4.2.40 - Lucina nassula (Conrad, 1846) Woven Lucine Low tide in tidal pool

Fig 4.2.41 - Mactridae (Lutraria lutraria) It burrows in mixed soft substrata, from the lower shore to about 100 m (mud dweller) http://www.marinespecies.eu/species.php?speci es_group=mollusca&id=784

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Fig 4.2.42 - Telliniidae (Capsa Lacunosa) from the Miocene of France

Fig 4.2.43 - Pectinidae (Pecten ziczac)

Fig 4.2.44 - Chlamys_tehuelchus

Fig 4.2.45 - Anomiidae (Anomia ephippium)

Fig 4.2.46 - Cardiidae (Trachycardium muricatum)

Fig 4.2.47 - Carditidae (Cardita crassicostata) LS

Fig 4.2.48 - Corbulidae (Corbula patagonica)

Fig 4.2.49 - Limidae (Antarctolima pygmaea)

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Fig 4.2.50 - Clausinella fasciata

Fig 4.2.51 - Barbatia novaezelandiae

Fig 4.2.52 - Anadara transversa

Fig 4.2.53 - Diplodonta semiaspera

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4.2.5b - Gastropods

Fig 4.2.54 - Turritellidae (Turritella cingulata) Typically found in the intertidal zone at the water's edge at a mean distance from sea level of -7 meters. http://zipcodezoo.com/Animals/T/Turritella_co mmunis/

Fig 4.2.55 - Cerithiidae (Ataxocerithium pullum) Today's cerithids are shallow intertidal to subtidal species, typically occurring at 1 m or less although some reports indicate some specimens have been collected from as deep as 2.6 m. It can be found in seagrass meadows and on unvegetated soft sediments. http://www.sms.si.edu/IRLspec/Cerithium_mus carum.htm A specimen from the Dam Formation was also found at locality A2_2040 but not illustrated

Fig 4.2.56 - Conidae (Conus fergusoni) Cone snails are predatory gastropods that live in shallow reef waters. They kill their prey with venom which they inject via radula teeth like small harpoons. The venom consists of numerous neurotoxic peptides that act pre- and post-synaptically to give rise to neurological symptoms of weakness, lack of co-ordination and disturbance of vision, speech and hearing. http://www.avru.org/compendium/biogs/A0000 61b.htm A1_1034

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Fig 4.2.57 - Xenophoridae (Xenophora solaris) Carrier shells inhabit tropical waters and are found from shallow down to extremely deep waters (On the bottoms of the continental shelf, upper slope and from the shallow subtidal waters). http://www.geocities.com/Eureka/Gold/9440/xe nop/xenecolPG.htm

Fig 4.2.58 - Naticidae (Natica [Glyphepithema] unifasciata) Today’s Naticidae live in shallow water, in depressions lined with muddy sand, occasionally on sparse seagrass beds. http://www.ciesm.org/atlas/Naticagualteriana.ht ml Fig 4.2.59 -Hydrobiidae (Hydrobia ulvae) Typically found on muddy sand, in estuaries and salt marshes. Sometimes also in lagoons and other areas of reduced salinity. Frequently associated with seagrass beds. Highest densities found mid-tidally but has been recorded down to 100 m depth. A small spiralling shell with six whorls. Up to 6 mm high but more typically around 4 mm. The shell is brown to yellow in colour. The body of the snail is a clear grey frequently with various pigment spots. http://www.marlin.ac.uk/species/Hydrobiaulvae .htm

Fig 4.2.60 -Fissurellidae (Fissurella [Diodora] volcano) They inhabit the mid to lower-intertidal zone, fixed to the underside of rocks. On rocks exposed by the low tide. http://www.articlearchives.com/sciencetechnology/biology/1487265-1.html

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The Miocene Guide of Qatar, Middle East (Dam Formation) Fig 4.2.61 -Balanidae (Balanus aquila) Member of the Balanus genus are normally found from the mid-shore to the sublittoral on rocks and artificial structures and is sometimes common in wave exposed situations. Also present on ships' hulls. Up to 30 mm in diameter and 30 mm tall, Balanus are recognised by their tapered, volcano-like shape. The shell wall consists of 6 purplish plates that are often vertically ridged, and sometimes separated at the apex leaving a jagged lip. Inside the operculum aperture, the tissue is marked with bright colours of pink, purple and blue. The tergoscutal flaps are brown to purple in colour, with blue and white spots. http://www.marlin.ac.uk/species/Balanusperfor atus.htm

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4.3 - Miscellaneous 4.3.1 - Stromatolites Definition Stromatolites are not fossils in true sense but they are stony structures constructed by organisms, such as algae and cyanobacteria.. They are produced by the carbonate precipitating and sediment binding activities of the successive mats of algae. They occur in rocks from Precambrian to recent and are found growing today off the coasts of the Bahamas and Australia. Environment of deposition The presence of stromatolites indicates that the sediments were deposited in a very shallow water environment (nearshore) and might have formed in a tidal flat environment or lagoons of tidal regions. The tidal flat is essentially a mudtrap and in arid climates such as Qatar, an area of high saline water. After deposition of stromatolite bearing carbonates, topographically restricted marine environment seems to have developed in the area during the Miocene. This restricted environment seems to have favoured hypersaline hot brines. Uses Apart from their use for biostratigraphic correlation and zonation, the stromatolites have proved to be good indicators of environmental changes and physiographic setting of the depositional site of the carbonate sediments. Stromatolites are used in biostratigraphic correlation, paleoenvironmental analysis and their association with phosphates, uranium, iron, manganese and magnesite have given them the economic importance. Classification Over the years several authors who studied stromatolites came up with their own scheme to classify them. The one that will be used in this research is the one from Logan et al (1960, 1964). Logan et al. proposed a descriptive nomenclature of structural formulae, which are combinations of initials of adjectives, adverbs and nouns (Table 4.3). The classification rests on the arrangement of basic geometric units (hemispheroids and spheroids), their lateral linkage, and their stacking. It is the first to emphasize the importance of synoptic morphology of the laminae (fig. 4.3.1), that is, how the algal structures appeared at any one time (fig. 4.3.2).

Fig. 4.3.1: Formation of laminae in stromatolites

Synoptic morphology of a lamina. H = height of stromatolite; h = relief of lamina. The laminae represent the microbathymetry during an interval of time at which each was at the active interface between already bound sediment below and the moving water with suspended particles above. It is at or near the interface, not at places already deeply buried, where biotic activity takes place, particles accumulate, the shape develops and inheritance is determined. http://leblanc.jacques.googlepages.com/fossilhome

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TABLE 4.3:

Classification of stromatolites by Logan, Rezak and Ginsburg (1964). Type

1)

Symbol

Laterally linked hemispheroids a. Close linkage (spacing between heads less than diameter of heads) b. Spaced linkage (spacing greater than diameter of structures)

LLH LLH-C

2)

Discrete, vertically stacked hemispheroids a. Constant radius b. Variable basal radius c. Inverted stacked hemispheroids (added to Logan’s classification by Kendall & Skipwich [1968, page 1042] to accommodate polygonal algal mats)

SH SH-C SH-V SH-I

3)

Spheroidal structures (oncoidal) a. Inverted stacked hemispheroids b. Randomly stacked hemispheroids c. Concentrically stacked spheroids

SS SS-I SS-R SS-C

4)

Compound forms a. Comprised of macrostructures (e.g SH) and microstructures (e.g. LLH) b. Vertical succession of different types (e.g. LLH growing into SH, and back into LLH types)

LLH-S

SH / LLH LLH Æ SH Æ LLH

Fig. 4.3.2: Some illustrations of Logan et al (1964) classification of Stromatolites (left) and their common names (right)

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Fig 4.3.3a (left): Lithological column of the Dam Formation at Khashm Al-Nakhsh indicating the vertical distribution of different stromatolite types (Khalifa et al, 1993). See also Fig 3.12a&b Note: Member “A” = Salwa member; and Member “B” = Al-Nakhsh & Abu Samrah members Fig 4.3.3b (Right): Depth zonation of stromatolite formation The cryptalgal laminites are made up of laminated fabric which results from the alternation of thick organic-rich layers and algal-rich dark laminae. Primary algal mats characteristically wrinkled into a series of small domes; the hemispheroids are linked laterally to other hemispheroids within the mat terrain to form type LLH stromatolites. The columnar type SH stromatolites are formed by the vertical stacking of discrete hemispheroidal laminae and are not linked to any other hemispheroids. The type SH stromatolites of Khashm Al-Nakhsh area probably formed by successive algal growth upon pre-existing original irregularities on an exposed intertidal erosion surface

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The Miocene Guide of Qatar, Middle East (Dam Formation) Fig. 4.3.4:

Stromatolites found in the Al-Nakhsh member of the Miocene Dam Formation in Qatar (Displayed from bottom to top of Al-Nakhsh member) A) concentrically structured stromatolites of unknown classification. Dill et al (2005) interpret them as microbial mat blisters caused by gas which

raises the thin microbial mats. After collapse blister mash down and form ring-shaped structures. Some harder cores have also survived this decay. A1_4008. This type of structure also occurs in the Eocene Rus Formation at a Mesolithic tool fabricating locality NW of Dukhan. In this case, the round structures and their centers were transformed into chert through a diagenesis process; (Pictures: Area01_4008_RusFmEx-01, Area-01_4008_RusFmEx-02)

B) SH in the Lower Al-Nakhsh member. This columnar type has a vast aerial extension in the Dam Formation. Columnar stromatolites may laterally grade into more domal structures. It occurs in protected basins with rather high tidal range under arid climatic conditions. A1_4002

C) LLH stromatolites and centimeter-thick laminae in clayey D) SS-C. Oncoid-like stromatolites with marlstones of the Middle Al Nakhsh Member. A2_5022 typical onion-shell exfoliation structure at the base of the Middle Al Nakhsh Member. A1_5005

E) SS-C (left) and SH / LLH (right). The internal structure F) SH. The maximum size of stromatolites of the SH / LLH closely resembles that of the SS-C. is achieved in beds immediately underneath the boundary between the Middle and A1_5029. Upper Al Nakhsh Member where domal Two fields of such stromatolites were also discovered at structures or thrombolite buildups– microbial mounds,, measuring 2 m across localities A7_5001 to A7_5004 and A7_5005 to A7_5006 cover a wide platform. A1_5060.

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Living Stromatolites Fig. 4.3.5:The "high-stress" environment of the Exuma Cays is created by the tremendous tidal currents and the 1 m tall sand waves they produce that regularly bury the Bahamian stromatolites. The stromatolite domes in a tidal channel off Lee Stocking Island are half buried by carbonate sand. The giant Bahaman stromatolites are composed primarily of finegrained carbonate sand (ooid sand) that is trapped and bound by the filamentous cyanobacteria Schizothrix sp.. (Alles, 2006)

Fig. 4.3.6:These domal stromatolites (A) are intertidal, while the oncoidal stromatolites (B) are subtidal. Hamelin Pool, at the south end of Shark Bay in Australia, is one of only two places in the world (the other being the Bahamas) with living marine stromatolites. Stromatolites are able to survive in the area because Hamelin Pool's water is twice as saline as normal sea water and sea grasses and many other forms of life cannot survive there. Hamelin Pool is actually a landlocked marine basin partially separated from Shark Bay by the Faure sill. This has helped to produce the hypersalination which in turn has ensured that the cyanobacteria remained isolated from fish and animals that would feed on them. (Alles, 2006) Fig. 4.3.7:Very small stromatolites growing at the present day on an old steel drum that has sunk into a soft sabkha at Umm Said, Qatar. The iron does not seem to inhibit the cyanobacterial growth. A hard or raised surface for attachment seems favourable for stromatolite growth. http://www.soton.ac.uk/~imw/QatarSabkhas.htm

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4.4 Plants There is no doubt that fossil plant remains occur in the Dam Formation (the dikakas of the Upper Al-Nakhsh member are good examples for instance), however they definitely are not found in great quantities and large sizes. The chances of finding large plant samples such as tree trunks or large branches (such as in Ad Dabtiyah, Whybrow 1987b) are very slim, to non-existent. Small species of plants growing in a Miocene mangrove is probably the best that one can expect (fig 4.4.1).

Fig 4.4.1 : Undetermined plant material (the pores and structure can be distinguished) probably representing the bark of a species growing in mangroves (A3_2037). These samples were found loose on a white limestone. They probably came from the layer above the limestone which is known to represent a beach / intertidal environment. Note that for some time the author thought they looked like eggshell fragments of a large bird, such as ostriches, as described by Bibi et al (2006) in the UAE; however, this personal diagnosis was later disproved. Fig 4.4.2 : Two thin-sections of the undetermined plant material in Fig 4.4.1. (Thanks to Jeremy Jameson for the preparation of this slide and others

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The Miocene Guide of Qatar, Middle East (Dam Formation)

5.0 – The Main Minerals 5.1 – Gypsum (Read also chapter 5.2 on “Nodular Anhydrites”) One of the softest minerals known to exist, gypsum is a gray to white-colored mineral that can be easily scratched with a fingernail, and is referred to chemically as a hydrous calcium sulfate. Some of its other, perhaps more familiar, names are based on its various forms of occurrence. For example, alabaster is a massive form; satin spar is a fibrous variety; and selenite is its crystalline form. Gypsum often occurs in varying proportions with anhydrite (calcium sulfate), a slightly harder and more dense mineral that lacks water in its chemical make-up (see "anhydrite" in chapter 5.2) Both gypsum and anhydrite belong to an interesting group of minerals called evaporites, which are sedimentary deposits composed of salts precipitated from sea water. Evaporites form in shallow or near shore marine and lake environments where evaporation has produced an unusually high concentration of dissolved salts, and where there is little or no circulation of fresh water. The precipitation of sediment from these hypersaline brines is associated with hot and relatively dry climatic conditions. In the marine setting, marginal and restricted basins with extensive coastal sabkhas are important. Present environments are in the Red Sea (continental rifting) and Arabian Gulf (continental collision). Gypsum has several principal uses. Ground gypsum is added to Portland cement to slow the setting time of the cement. Pulverized gypsum, and to a lesser extent anhydrite, is used in agriculture as a soil conditioner and as an animal-food additive. The best known use of gypsum is as the principal ingredient in the manufacture of wallboard and plaster. This is possible because of gypsum's unique property of rehydrating with the addition of water after having been ground, calcined (baked to a powder), and mixed with other wallboard ingredients. Anhydrite is considered a contaminant in this case because it cannot be hydrated like gypsum. The general genetic model hinges on the deposition of soluble minerals by evaporation in salt lakes (Salinas) and low-lying salt flats (sabkhas – as is the case for the Dam Formation) and in generally shallow marine basins restricted from circulation with the world ocean and suffering from a deficit of input of fresh water, and by precipitation from subsurface brines in both marginal marine and inland arid basins.

Fig. 5.1: Process 1: Explaining how evaporite (gypsum and salt) deposits are formed http://leblanc.jacques.googlepages.com/fossilhome

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Fig. 5.2: Process 2: Evaporite precipitation in a restricted ocean

Fig. 5.3 & 5.4: Process 3: High evaporation from the surface of the flat “pumps” seawater landward and up through the sediment where evaporites are deposited (fig. 5.6). Left: a sabkha in Umm Said; Right: looking for gypsum desert rose in the Dukhan sabkha As mentioned above, the evaporitic cycle is currently at work in the Arabian Sea, however, in order to understand well the mechanism involved, let’s use a fictional and drastic example in which the geological activity in the Straight of Hormuz, located between Iran and the United Arab Emirates, increases suddenly to cause either the sea bottom of the Straight to rise up or the Straight itself to be blocked by huge amount of rocks and debris. Since no or very little influx of fresh water occur in today’s Arabian Sea and that the sea is located in a very arid climate, the consequences of this geological activity would result in the creation of a gigantic closed evaporitic basin stretching from the Straight of Hormuz to Kuwait. As such, with time the minerals to be precipitated at the bottom from seawater would follow a pattern according to their sensibility to dissolution: first would be the aragonite mineral and carbonates (such as dolomite) then the gypsum (sulphate), halite (salt), sylvite (potassium) and tachyhydrite. As these minerals precipitate, the density of the brine would increase through evaporation until no water is left (Fig 5.1) http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) Gypsum almost universally is associated with anhydrite (such as in A2_5006) because economic deposits of gypsum normally result from near-surface rehydration of anhydrite. Gypsum represents the stable phase of calcium sulphate at the surface, whereas anhydrite represents the stable phase at depth. Gypsum and anhydrite deposits commonly are interbedded with, or rest upon, limestone or dolomite. In some areas a continuous deposit of gypsum and anhydrite may occur, but in most places gypsum and anhydrite are interbedded with “red beds” limestone (as in the Dam Formation), dolomite or salt. The gypsum deposits of the Dam Formation in Qatar: Two mechanisms are known to have formed the gypsum beds in the upper portion of the Dam Formation: the first one was the deposition of gypsum in a supratidal environment such as in a sabkha (see http://www.soton.ac.uk/~imw/Qatar-Sabkhas.htm ); the second was when the ground waters came in contact with buried gypsum beds (from the Miocene or Eocene) and these were then carried in solution to the surface where they were re-precipitated in existing rock fractures or as a replacement mineral for other dissoluble minerals. With regards to the unique occurrence of large (+1m) gypsum crystals, Dill et all (2005) offer the following explanation: “Stromatolitic structures [see chapter 4.3.1 on stromatolites] were crucial as to the permeability and porosity for the percolating fluids. A tremendous increase in the size of SH stromatolite may be recognized along with an increase in thickness and crystal size of gypsum. The giant gypsum crystals resulted from an early diagenetic reaction at shallow depth. Freshwater and seawater fluids involved in this process lead to a dissolution and recrystallization of earlier marine evaporites.” Also, Drs. Cornelis (Cees) Kok, Head of Geology Laboratory at Qatar Petroleum, answered the following in an email dated June 17th 2009 upon my request to comment on Dill et al (2005) theory above : "There are a number of issues: 1) There must have been a very steady, very rapid supply of CaSO4 dissolved in water. Seawater alone through evaporation would not contain enough dissolved CaSO4 to "feed" the giant crystal growth; an additional source from already deposited evaporitic Gypsum could be postulated as this additional source. Because seawater already contains Gypsum to its natural saturation point, freshwater, which can carry more CaSO4 must have played a role. So yes, I can accept (part of) Dill et al (2005) explanation. The crystals must have had the accommodation space to form, so a shallow (uncompacted) environment like the Desert roses is very likely. We then must explain the prevailing lateral accretion rather than a vertical accretion. This probably reflects the physiochemical-hydrological layering in the shallow sediments. 2) I do not know of any other places with similar crystals of Gypsum. The Messinian in Sicily contains large cauliflower crystallization features, beautifully exposed on the Southern most tip of the island along the beach. You should see it at sunset! However, these are probably formed in a supersaturated brine at the bottom of a rapidly desiccating Mediterranean (Waterfall at Gibraltar, the Messinian salinity crisis). They do not reach the same horizontal span. Some samples should be taken to look for growth lines and irregularities in growth in the various arms of the crystals. I do not think there is a biologic connection to them”. A very good example of the dissolution & re-precipitation/crystallization process that Dill et al mention is shown in the satellite image in Fig. 5.5 where the beds of the Dam Formation in our http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) entire Area 2 are shown as being completely convoluted, giving the appearance of a large doline. These convoluted beds are explained by the dissolution of buried gypsum and subsequent collapse of the Miocene layers above (Fig. 5.7). Since several beds of gypsum occur within the Al-Nakhsh (and underlying Rus formation) the dissolution & re-precipitation process must have taken place at several occasions within the period of deposition of this member. It is important to note that in our Area 2, the Qatar National Cement Company (QNCC) is currently mining the re-precipitated gypsum (see bottom-left corner of fig. 5.5)

Fig 5.5: Satellite image of Area 2 showing the convoluted beds of the Dam Formation. This phenomenon is due to the dissolution of buried gypsum beds and subsequent collapse of the Miocene layers above. Note the QNCC gypsum quarry at the bottom left corner.

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Fig 5.6: Typical selenite and gypsum environments and facies (Schreiber, 2008)

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Fig 5.7: Principal features of Solution collapse (Hunting, 1983) http://leblanc.jacques.googlepages.com/fossilhome

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Fig 5.8: Large dissolution holes or “dolines” can Fig 5.9: A ancient doline in the Middle Salwa form in highly gypsiferous material (this modern Member of the Dam Formation. (A1_2014) example is not from Qatar)

Fig 5.10: Large doline in the Middle Salwa Fig 5.11: Large gypsum crystal (A1_5002) Member of the Dam Formation. (A1_2046)

Fig 5.12: Large radial gypsum crystals (A1_5003)

Fig 5.13: Large radial gypsum crystals still inplace (A1_5019)

More information on gypsum can be found at: http://en.wikipedia.org/wiki/Calcium_sulfate http://en.wikipedia.org/wiki/Gypsum

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The Miocene Guide of Qatar, Middle East (Dam Formation) The gypsum deposits of the Dam Formation in Saudi Arabia: The only deposit of economic importance in the Miocene Dam Formation of Saudi Arabia is at Khashm Umm Huwayd (Fig. 5.14) about 54 km Northwest of our Area 2, just across the Bay of Salwa. This locality, which consists of six beds of massive gypsum each 20 to 50 cm thick intercalated in a clayey carbonate sequence, also shows the convoluted beds from a satellite image. The gypsum content averages 85 percent; impurities are mainly carbonates and clay and the anhydrite content is less than 5 percent. Resources are estimated at 9.6 Million tons and since they have no overburden they are easily accessible. Gypsum slabs are quarried for use as a cement retarder by the Saudi Cement Company of Al Hofuf.

Fig. 5.14: Gypsum occurrence and quarry locality in the Dam Formation of Saudi Arabia. http://www.sgs.org.sa/index.cfm?sec=74&sub=196&sub2=217&pageNumber=2

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5.2 - Nodular anhydrite or chicken-wire structure (Read also chapter 5.1 on “Gypsum”) Nodular anhydrite is a diagenetic structure in calcium sulfate evaporates. It is a type of anhydrite deposit where seeping ground water gradually deposited large amounts of anhydrite in the sediment, replacing most of it, so that a cross-section of it looks somewhat like the coarse wire netting often used to confine poultry (Fig.5.21) The creation of Nodular anhydrite first starts with the deposition of gypsum, a type of evaporite mineral (See chapter 5.1 on Gypsum). Although gypsum is common in Recent evaporitic sediments and primary gypsum is preserved in some Neogene evaporite formations that have been buried to only relatively shallow depths (as it is the case for the evaporites of the Dam Formation), it is characteristically not found in borehole cores taken from evaporites at depths greater than approximately 1000 metres where anhydrite is normally the only calcium sulphate mineral present. It is therefore generally believed that gypsum becomes unstable in consequence of the increase in rock temperature which accompanies burial and that at some critical depth, determined by the local geothermal gradient and the salinity of the connate waters, it is made over into anhydrite (Process 1 discussed below). However, anhydrite is also known to occur in comparative abundance in certain present day and Neogene evaporites, where some of it demonstrably formed by syndepositional alteration of gypsum (Processes 2 and 3 discussed below).

Process 1: Nodular anhydrite and deep burial In the gypsum-anhydrite diagenetic cycle shown in fig. 5.15 below, gypsum is converted to anhydrite upon burial, and then the anhydrite is usually reconverted to gypsum as it makes its way to the surface again. It is during this process that the chicken-wire mosaic is created (see fig. 5.16). When gypsum is replaced by anhydrite, there is a 38% loss in volume, because of the great difference in density between the two minerals. So there is great extra compaction on the way down. Conversely, on the way up the anhydrite is reconverted to gypsum, provided that extra water is available. This expansion tends to cause even more local deformation of the deposit. The change from anhydrite to gypsum on the way up is usually delayed until the near-surface zone of influence of surface groundwater is reached. Note: this process is not believed to have been at work in the Dam Formation

Fig. 5.15: The gypsum-anhydrite diagenetic cycle http://ocw.mit.edu/NR/rdonlyres/Earth--Atmospheric--and-Planetary-Sciences/12-110Spring2007/D20F3F03-555E-4EBA-AD9D-BFAF5AF8A3C5/0/ch6.pdf

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Fig. 5.16: The gypsum-anhydrite cycle showing mineral and textural changes, from the surface, into the subsurface and on uplift. ( http://opencourseware.kfupm.edu.sa/colleges/cs/es/geol464/files%5C5-_Handouts_Lec13.pdf ) The main sites of marine sulphate precipitation today is in the high intertidal and supratidal zones. Gypsum is being precipitated displacively within the sediments as discoidal, rosette, selenite and twinned crystals from less than 1 mm to more than 25 cm in size. Dolomitization of carbonate particles is commonly associated with gypsum precipitation, as a result of the increased Mg/Ca ratio. Gypsum is the most common precipitate within the sediments of inland sabkha, where it forms the familiar desert roses. If the evaporation is sufficiently intense then with increasing concentration of pore fluids across the sabkhas, the gypsum crystals are hydrite crystals. Continued displacive precipitation of anhydrite results in closely packed nodules with host sediment. The nodular texture produced is referred to as chicken-wire anhydrite.

Process 2: Nodular Anhydrite Formed by Syndepositional Alteration of Gypsum in Present Day Sabkhas. Anhydrite is forming at the present day on a regional scale in the inland sabkha of Dukhan in Qatar (Figs 5.18 & 5.22) (Al-Youssef et al. 2003 & 2006) and coastal sabkha of ABu Dhabi in the UAE. The anhydrite is characteristically nodular and the nodules grow displacively (Fig 5.17), mostly in the sediments of the supratidal facies. Some of the nodules clearly arose by alteration of earlier formed gypsum, but others evidently without gypsum precursors. Further, anhydrite nodules have been seen to hydrate to gypsum as a result of dilution of the sabkha brines following heavy rainstorms, but those are uncommon events and the gypsum is made back into nodular anhydrite http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) within a few months as high salinities become re-established. Irrespective of their origin all of the nodules have essentially similar crystal fabrics.

Fig. 5.17: Where gypsum crystals commence to undergo alteration to anhydrite, cavernous hollows develop in them which are occupied by loose accumulations of tiny anhydrite crystals. The corroded appearance of the hollows leaves little doubt that the change from one mineral to the other was a dissolution/precipitation process. As alteration proceeds each gypsum crystal is made over into a loose mass of anhydrite crystals that first roughly pseudomorph it, but as more and more anhydrite crystals are added the pseudomorph swells out into a nodular mass that ultimately loses all resemblance to its parent. The nodules appear to grow by nucleation of new crystals within the framework of earlier formed ones, and as the new crystals grow they push the others aside and those in turn displace the surrounding host sediment. The anhydrite nodules are remarkably pure, and that purity is a measure of the efficacy of the platy shapes of the crystals in pushing the surrounding sediment aside. Where anhydrite nodules grow in close proximity to one another and coalesce, the displaced sediment comes to form partitions between them and gives rise to the familiar mosaic or chicken wire appearance. (Shearman, 1983) In the north-eastern sector of the Dukhan sabkha (Salt lake) (fig. 6.5.6) Al Youssef et al (2006) report the following percentage of evaporite with values almost double to those outside of the Salt Lake sector: Anhydrite - 33% (or 48% excluding clastic and carbonate minerals). It occurs as white nodules at a shallow depth of about 20 cm below the surface. Algal (microbial) mats are present below the anhydrite nodules. Salt - Second dominant evaporite (no % mentioned) which forms both at surface and shallow depth Gypsum - 11% (or 22% excluding carbonates and clastic minerals). It occurs as crystals and crystal fragments at different depths within the sediments, mainly above the groundwater level. The shape of these crystals include lenticular and sublenticular, acicular, elliptical, semi-elliptical, prism-like, pyramidal, pseudo-tetragonal and intergrown crystals http://leblanc.jacques.googlepages.com/fossilhome

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Fig 5.18: Vertical distribution of carbonate-algal-evaporite facies across sabkha. (Butler G. 19??)

Process 3: Nodular Anhydrite in Neogene Evaporites Many of the Neogene evaporites exposed at outcrops in Qatar include beds of unaltered primary gypsum. They are generally thick massive beds of competitively grown gypsum crystals which are clearly subaqueous in origin. Field work by previous authors indicate that at no time had they been buried to depths of more than a few hundred metres and those depths were evidently insufficient to carry them out of the stability field of gypsum. In some places the beds of primary gypsum enclose nodules of secondary gypsum (Figs 5.19 & 5.20), but the secondary gypsum carries tiny corroded relics of anhydrite crystals and those demonstrate that the nodules were originally nodules of anhydrite. The hydration of the anhydrite to gypsum was a late effect caused by introduction of meteoric water during exhumation of the rock. The relationships of the former anhydrite nodules to the primary gypsum which encloses them leaves no doubt that the nodules formed by alteration of the primary gypsum. The frequency of the nodules varies from bed to bed. They are absent from many beds, sparsely scattered in others where they are usually developed at particular levels; but they are so abundant elsewhere that only mere vestiges of the original gypsum remain. The extent of alteration varies randomly from bed to bed in any stratigraphic succession, and the change clearly took place on a bed by bed basis. The only reasonable conclusion is that the change from gypsum to nodular anhydrite was the result of changes in the chemistry of the interstitial brines penecontemporaneously with deposition.

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Fig 5.19: Primary gypsum in part made Fig 5.20: Syndepositional nodular anhydrite, now over into nodular anhydrite; now secondary gypsum, formed by alteration of a primary secondary gypsum (Shearman, 1983) gypsum laminite (Shearman, 1983)

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http://www.soton.ac.uk/~imw/Qatar-Sabkhas.htm Fig. 5.21: Chicken-wire structure in secondary Fig. 5.22: Displacive nodules of anhydrite have gypsum seen on a polished outcrop (not from formed in the muddy sand of the capillary zone a Qatar) few centimetres beneath the thin surface halite crust at the margin of the Dukhan sabkha. These http://www.soton.ac.uk/~imw/Qatarare modern analogues for the anhydrite nodules Sabkhas.htm that are common in ancient evaporite deposits

Figs 5.23: Top pictures and bottom left: Anhydrite nodules of the Middle Al-Nakhsh at “Conical Hill”, as named by Whybrow (1987) A4_5001, probably formed under “Salt Lake” conditions. The mineral “Celestite” is also associated with the nodules. Bottom right: A5_5002 (“normal” sabkha conditions) http://leblanc.jacques.googlepages.com/fossilhome

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6.0 – Geological features 6.1 - Beachrocks Beachrock is defined as "the consolidated deposit that results from lithification by calcium carbonate of sediment in the intertidal and spray zones of mainly tropical coasts." They consist of multiple units, representing multiple episodes of cementation and exposure. Beachrock that forms below the foreshore has an upper surface slope that tends to mimic that of the seaward dipping (4 10°) internal beach bedding. Beachrocks are restricted to warm tropical seas, in essence the same latitudes to which coral reefs are restricted. They are created by the rapid cementation of beach sediments in the intertidal zone which leads to the formation of characteristic lithified structures; such as internal laminations caused by grain-size variations, seaward-dipping layers and bubble-shape voids. Beachrock units form under a thin cover of sediment and generally overlie unconsolidated sand. They typically consist of multiple units, representing multiple episodes of cementation and exposure (fig 6.1) On retreating coasts, outcrops of beachrock may be evident offshore where they may act as a barrier against coastal erosion. Beachrock presence can also induce sediment deficiency in a beach and outsynch its wave regime. Because beachrock is lithified within the intertidal zone and because it commonly forms in a few years, its potential as an indicator of past sea level is important. Beachrocks are located along the coastline in a parallel term and they are usually a few meters offshore. They are generally separated in several levels (Figs 6.1 & 6.2) which may correspond to different generations of beachrock cementation. Thus, the older zones are located in the outer part of the formation when the younger ones are on the side of the beach, possibly under the unconsolidated sand. They also seem to have a general inclination to the sea. There are several appearances of beachrock formations which are characterized by multiple cracks and gasps. The result from this fact is an interruptible formation of separated blocks of beachrock, which may be of the same formation. The length of beachrocks varies from meters to kilometers, its width can reach up to 300 meters and its height starts from 30 cm and reaches 3 meters. Different colors of the formation indicate different zones. Following the process of coastal erosion, beachrock formation may be uncovered. Coastal erosion may be the result of sea level rise or deficit in sedimentary equilibrium. One way or another, unconsolidated sand that covers the beachrock draws away and the formation is revealed. If the process of cementation continues, new beachrock would be formed in a new position in the intertidal zone. Successive phases of sea level change may result in sequential zones of beachrock. Beachrocks in the Dam Formation of Qatar are found mainly in the Lower and Middle Al-Nakhsh Member where they display clasts of other broken up and reworked rocks, together with the very familiar oolites (Chapter 6.2). In the Lower Salwa, however, there are some localities where multiple unit beachrocks are exposed and can easily be observed from space; the sector around A1_1014 (Figure 6.4), which displays a general orientation going from Southeast to Northwest, is one of them. In these beachrocks can be found rib remains of Miocene dugongs, ironized deformed cross-beds, coral debris, burrows and other interesting features. (Another similar locality is at A3_1050).

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Fig 6.1: Simplified representation of how a beachrock is formed. (Shinn 2004)

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Fig 6.2: Holocene (A & C) and recent (B) beachrock off the coast of the Bahamas (Shinn 2004)

Fig 6.3: Oolitic beachrock from the Dam Formation showing clasts and other debris. (A1_5017)

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Fig 6.4: View of Lower Salwa multiple unit beachrocks (sub/inter tidal) from space in Area 1. At location A1_1015 can be found a rib from a Miocene dugong.

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6.2 - Oolites Oolites (fig. 6.5) are a type of ooids (oolites, pisolites, oncoids, and oncolites) and are formed by a series of concentric layers surrounding a nucleus. They generally form in agitated marine environments including tidal sand bars or tidal deltas between barrier islands (see also appendix “A”). Qolite sands form important reservoirs, of which the Permian Khuff Formation of Qatar is one of the best known. Most recent ooids from modern marine settings like the Bahama Banks exhibit concentric coatings that have an organized microstructure of tangentially arranged aragonite needles. However, some recent ooids from the Arabian Gulf in the vicinity of Qatar have a radial fabric of needles. A similar fabric is common to most ancient ooids. The size of ooids is controlled by rate of precipitation and abrasion. Oolites generally range between .5 and 1mm in diameter. Ooids with asymmetric coatings and superficial oolites form in quiet water. Occasionally broken radial ooids may act as the nuclei for other ooids suggesting that the radial Fig 6.5: The several types of oolites. fabric is developed during deposition. Breakage is common in oolites that collect on salt flats http://strata.geol.sc.edu/thinsections/caco3where halite precipitation has weakened the ooids.html radial fabric. During our field investigation of the Dam Formation it was observed that oolites were always in close association with beachrocks (see chapter on beachrocks)

Fig 6.6: Oolites. Area-01_5017b

Fig 6.7: Depositional setting of oolites

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6.3 - Aeolianite Some definitions Aeolianite: A near-coastal landward feature composed of cemented dune sands. Those with a rich content of carbonate have a pale yellow, sometimes almost white, colour in contrast to the reds and deeper yellows of quartz-rich dune sands. The colour contrast is possibly because contained shell fragments are almost white in color, but more likely because light-colored sands may never have been in the physical environment where reddening seems to occur – at the level of a fluctuating water table. Dikakah: Sand drifts in and around scrub vegetations. Dune: Accumulation of wind-blown sands that possesses one or more slipfaces. Its size is dependent on the availability of sand and the ability of the wind to carry sand to the top without removing it again. The finest sand grains are usually found at the crest. There are several types of dune; barchan dunes are one of them. Interdune: A geometric surface commonly enclosed or at least partially bounded by dunes or other eolian deposits such as sand sheets. Sediments in an interdune area may include both subaqueous and saubaerial deposits. A sabkha, for instance, is a type of evaporite interdune. It is frequent in trenches of modern interdune sediments to reveal a thin unit of interdunal sediments underlain by sediments of a preexisting dune or some other facies (Fig. ??). The recognizability of interdune sediments increases roughly in proportion to the degree of enclosure of the interdunes. Nonenclosed interdunes between widely spaced dunes, 0.8 to 1.6 km apart, have sedimentation features resembling sand sheets.

Several aeolianites occur within the Upper Al-Nakhsh Member of the Dam Formation in the surveyed areas (Areas 1 and 7); however, only two show features typical to sand dunes. The first one, which is also the best preserved (A1_6005), has been briefly described by Dill et al 2007 as (fig. 6.3.3) “Red, fine-to-medium grained sandstones (A) with planar cross bedding are separated from subjacent sandstones, and (B) of the same lithology by an uneven reaction surface. The red bedsets on top of the reaction surface display largescale trough cross-stratification with a tangential basal contact. Sand ripples are common. They occur only near the tangential basal contacts of foresets, immediately above the first-order bounding surfaces”. A further analysis by Dr. Jeremy Jameson of ExxonMobil (personal communication) has also determined that the whole feature (38 metre in length) is a lithified aeolian dune sand overlayed by an inter-dune sand, as seen at the bottom and top respectively of fig. 6.3.2. Very fragile dikakah can also be observed in small quantities (Fig. 6.3.4). These dikakah are ringed by small crystals, thought to have crystallized when sulphates in the water were not absorbed by the plants’ roots; such crystal sheaths may have cutoff the supply of water to the plant and led to its death (Glennie 2005). The second location (A1_6016) was discovered by the author and is located 1.2 kms north from the first locality. The red Aeolian sands are present on the eastern flank of the Al-Nakhsh Hill and partly buried by the Hofuf gravels (Fig. 6.3.7). While not as spectacular as the first locality, this sand also shows the typical features of a sand dune, including some dikakah as decribed above. Locality A7_6001 is a good example of a windblown sand which has never developed into a dune (see picture in photo album). It occurs at the center of a doline and is shown as a small patch of a consolidated and laminated sandstone. Loose weathered red sands also occur in the doline. This locality represents a sand which was blown over an open and flat area. http://leblanc.jacques.googlepages.com/fossilhome

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Fig. 6.3.1: A 38m long aeolianite; Area-01_6005

Fig. 6.3.2: Area-01_6005 showing the dune sands overlaid by an interdune deposit. The erosional contact is obvious

Fig. 6.3.3: See Dill et all’s description above

Fig. 6.3.4: Aeolianite displaying dikakahs (Area-01_6005)

Fig. 6.3.5: A sedimentary feature in the interdune (Area01_6005)

Fig. 6.3.6: Plants growing on a modern dune; once fossilized, the roots and small branches will form dikakahs

Fig. 6.3.7: Area-01_6016 showing the second aeolianite. Use vehicle on top of the hill as scale (top left corner)

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Fig. 6.3.8: Cross-sectional view, parallel to wind direction, showing lenticular relationship of interdune deposits to barchanoid dunes (Ahlbrandt et al, 1981)

Fig. 6.3.9: Hypothetical model to explain complex cross-stratification patterns in transversal sections of barchan dunes. A) Oblique bird's eye view of barchan showing longitudinal and transversal sections of internal (cross-) stratification. B) Temporal change in dominant wind direction shifts barchan sideways and forward, and migrates internal cross-stratification in transversal sections as shown. C) Complex transversal cross-stratification patterns may arise from minor but repeated shifts in dominant wind direction. (Weijermars, 1999a)

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6.4 - Hummocky Cross Stratification A reason geologists get excited when they see Hummocky cross stratification (HCS) is that it’s a fantastic indicator of a particular environment — a subaqueous environment shallow enough to feel the effects of waves. They occur in shelf conditions but also on the shoreface and in the surf zone. Hummocks are three-dimensional low-angle features of several meters long and a few decimeters high. Hummocks are preserved in deposits with hummocky cross stratification (HCS) as low-angle planar bedding, commonly in bundles reflecting the length and migration of the hummocks. They will typically be found in a stratigraphic succession sandwiched between offshore shale/siltstone and shoreface and/or delta-front deposits. How Hummocky cross stratifications form: HCS are believed to form as a result of combined flow which only occurs when a current is generated by a storm at the same time as high-amplitude waves reach deep below the surface. During the few days prior to a big storm, energy accumulates on the lagoon side of a barrier bar (fig. 6.4.1). When the storm hits the area, the current in the tidal channel becomes much stronger than in the normal daily tide activity in the said channel. The strong current takes sand out of the lagoon (red lines) into the deeper water (blue lines) in temporary suspension and as it is deposited the oscillatory motion caused by the waves results in deposition in the form of hummocks and swales (Fig 6.4.3). Then the resuspended sediments quickly settle as a series of laminae to more or less drape the undulating topography. If the area is receiving sediment, say from the strong bottom currents scouring closer to shore, the next big sea floor slap won't scour down as deeply, thus allowing a series of hummocky cross beds to be preserved (see figures below). It is also possible that as a storm wanes, successively weaker waves suspend less and less sediment, thus allowing the sequence to be preserved. (modified from Prothero and Schwab) Fig 6.4.1: One possible example for the creation of Hummocky cross stratifications - the overflow of a Miocene lagoon cutting through an intertidal / barrier bar during a storm.

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Fig 6.4.2 HCS occur in fine- to medium-grained sand and typically below fair weather wavebase by larger waves produced during storms

Fig 6.4.3 Diagram showing the two different types of current flow involve in the creation of HCS

Fig 6.4.4: Block diagram of one of the common styles of HCS

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Fig: 6.4.5: HCS overlaying a columnar stromatolite horizon (Locality A1_4022)

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6.5 - Tepee Structures One distinctive feature of peritidal limestones is the tepee structure. Tepees are disruptions of the bedding into "pseudoanticlines" and in plan view the tepee crests form a polygonal pattern. Tepees occur on the scale of tens of centimetres to several metres across. They mostly form on intertidalsupratidal flats as a result of the cementation and expansion of the surface-sediment layer. Upward movement (resurgence) of ground water, marine or meteoric, is a contributory factor in some cases. Elongate cavities (sheet cracks) commonly form beneath the uplifted slabs and in these, pisoids may form, as well as vadose cements such as dripstone and flowstone. These tepees usually are associated with planar stromatolites, desiccation cracks and intraclast conglomerates. Modern examples of these tepees, some with the spelean-pisoid association, occur on supratidal flats and around saline lakes in South and Western Australia. Tepees also form in the submarine environment, for example, where hardground surfaces have expanded through the cement precipitation. These are well developed off the Qatar Peninsula.

Fig 6.5.1: The anatomy of tepees

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Fig 6.5.2: Example of tepee formation on Barrier islands (Kendall 2005). However, they can also form in a sabkha environment. (figs. 6.5.6 & 6.5.7)

Figs 6.5.3 and 6.5.4: Sketch comparing mode of formation of tepees in crusts and tepees in caliche layered host rocks. In "A", lateral expansion results from early cementation in cracks and pores, minerals transformations, etc, and results in lateral displacement. In "B", caliche is introduced by way of the initial crack and is deposited in the shales, causing expansion and vertical displacement

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Fig 6.5.5: Tepee structures and LLH stromatolites and centimeter-thick laminae in clayey marlstones of the Lower Al Nakhsh Member

Fig 6.5.6: The author standing over the “Salt Lake” portion of the Dukhan sabkha which displays halite Fig 6.5.7: A closer look at a tepee structure being polygonal features. Tepee structures are being formed formed in today’s Dukhan sabkha in Qatar (picture by Dr. Jeremy Jameson)

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7.0 – Acknowledgments Other than my wife who has always been very supportive of this demanding hobby, I am indebted to several individuals for their unwavering support, insight, enthusiasm, and generosity to help me bringing this document to the public attention. I thank especially: 1) Professor Dr. habil. Harald G. Dill ( www.hgeodill.de ) from the Federal Institute for Geosciences and Natural Resources in Germany for answering the initial questions I had with regards to the fossils and geology of the Dam Formation in Qatar; 2) Dr. Jeremy Jameson, Sedimentologist at ExxonMobil, for his considerable time and attention to answer all my geology and sedimentology related questions every time I returned from field trips. Thanks also to him for the thin-sections of the Middle Salwa wood samples described in the document together with their photographs. 3) Mr. Hussain Al-Ansi, Head of Geology Studies at Qatar Petroleum, for reviewing and commenting on the content of this publication; 4) David D. Puls, Reservoir Geoscientist at ExxonMobil, for recommending me and allowing me to participate in a Carbonate Workshop sponsored by ExxonMobil for Qatar Petroleum employees. This workshop was a turning point in opening my eyes and mind to the processes at work in the creation of a sabkha 5) Dr. Cornelis (Cees) Kok, Head of the Geology Lab at Qatar Petroleum, for sharing his knowledge on the foraminifers (fossil and recent) of Qatar and his insight on mineral deposition and the burrowing activities of organisms living in marsh environment; 6) Dr. Iyad S. Zalmout, vertebrate paleontologist at the University of Michigan (http://www.paleontology.lsa.umich.edu/Directory/individual.html?person=Zalmout ), for identifying all the sirenian/dugong bone material described herein. His wide knowledge on marine mammals and all the fossil dugong sites in the world, including those nearest to Qatar (Egypt and Pakistan), was invaluable. 7) Dr. Friedrich Pfeil ( http://www.pfeil-verlag.de/ef1.html ) and Dr. Iyad S. Zalmout, paleontologist at the University of Michigan, for identifying the specimen found in the Lower Al-Nakhsh sub-member as a myliobatis toothplate; 8) Dr. Paul Taylor of the Natural History Museum (UK), for his identification of the bryozoa: http://www.nhm.ac.uk/research-curation/staff-directory/palaeontology/cv-5472.html ; 9) Dr. Carrie E. Schweitzer, Department of Geology of Kent State University, for identifying and commenting on the samples of crabs and shrimps found in the Dam formation; 10) Dr. Faysal Bibi (Yale University) and Dr. Thomas A. Stidham (Department of Biology, Texas A&M University), for commenting on whether a sample found in the Middle Salwa was of eggshells or wood. (www.briankraatz.com/bpk/CV_files/Bibi_et_al_2005.pdf ) 11) Dr. Raquel López Antoñanzas, "Museo Nacional de Ciencias Naturales" in Spain, for commenting on some fossils found in the Dam, and allowing the use of pictures and text from her Doctorate thesis. Dr. Antoñanzas is currently conducting a study on a 10kg sand sample of the Upper Al-Nakhsh dune (A1_6005) described in chapter 6.3. Her interest is to find small vertebrate remains. http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) 12) Mr. Faisal Al-Naimi, Director of the Antiquities Department at the Qatar Museum Authority (QMA) (http://www.qma.com.qa/eng/index.php/qma/home ) for commenting on the provenance and use of a flint (archeological artifact) found at one locality within our Area 2. QMA is also to be thanked for officially receiving and storing all our Miocene and Eocene dugong bone material collected over the past 2.5 years. 13) Mr. James Kuzych, wellsite geologist at Qatar Petroleum, for showing me a Rus Formation Mesolithic site in northwest Dukhan where structures similar to the “blister” stromatolites of the Dam Formation can be seen. 14) Mrs Frances Gillespie for allowing to re-print her 1998 article on the archeological site of Jarr Umm Tuwaim 15) Mr. Dave Smith, QA/QC engineer at Maerks Oil, for pointing out to me the anhydrite nodule localities surrounding A4_5001.

I hope I have not forgotten anybody. If I did be assured that it was not intentional. I value very much the help I received from all.

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8.0 –Recommendations and Conclusions 8.1 - Recommendations One of the reasons this research was undertaken was to recommend to the State of Qatar some localities worth protecting/preserving for the benefit of more studies and/or enjoyment by the public at large and future generations. We sincerely believe that some of the localities recommended below could become one day as important as those localities in Saudi Arabia mentioned earlier in the text, and play an important role in presenting a better picture of the Arabian Peninsula’s past as a whole for that Period. So far, in Qatar, the term "cultural heritage" has been applied mainly to archeological structures or past human activities and remains. To our knowledge, the country does not have yet a list of paleontological sites deserving to be preserved and protected. Decision on the particular sites selected to be protected corresponds ultimately to the political authorities of a nation. Normally, palaeontologists play an important advisory role before the political authorities in selecting the relevant sites and providing the most adequate measures to protect them; however, Qatar does not have any paleontologists in its ranks. For the time being, it can only rely on the collaboration of its local and expatriate population together with cultural and professional associations and Institutions such as the Qatar Museum Authority (QMA), the Qatar Natural History Group and the Qatar Geological Society to spread the knowledge and importance of protecting similar sites. In short, we must all be social players in this arena. The four selected sites below are our recommendations for protection. We are not asking the government of Qatar to designate them as "protected sites" but we do recommend them for protection if the authorities have already a plan in mind to include paleontological sites in their Cultural heritage laws. If this is the case, an expert paleontologist should conduct a thorough study of each site before giving his own recommendation to the country. Until such designation is made official (if ever), we are asking the weekend fossil enthusiasts visiting these sites to please approach them with the awareness of responsible individuals. Do not collect any remains, do not litter and drive on any of the sites and, if you do find new specimens/localities, report them to either the author or the Qatar Museum Authority (QMA). Our recommendation of sites which deserve to be protected for the patrimony of the country are: Geological feature 1) The Upper Al-Nakhsh dune/interdune sediments at locality A1_6005. This 38 metre long feature is the only one in Qatar of this time period and as well preserved. Quarrying nearby should be prohibited. Paleontological remains 1) The whole sector around A3_1019, as show in figure 4.1.18, contains important and large quantities of fossil dugong remains. The author also believes that these remains, once studied by expert paleontologists, will lead to dugong fossil teeth and/or skull that will allow to put a name on the species of these animals that roam the Miocene sea. 2) Locality A1_1029 contains at least seven (7) dugong ribs and two vertebrae on a small limestone mound 3) The sector around locality A1_2115 should be protected and investigated more. Several dugong remains were found within a limited range.

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8.2 - Conclusions The Miocene Dam formation in Qatar has revealed itself has an important repository of both unique geological features and paleontological remains. It has all the preserved characteristic features of an ancient sabkha and is a prime candidate to be studied by petroleum geoscientists in order to understand similar sub-surface carbonate deposits, such as the Jurassic Arab-C&D reservoirs in Qatar, in which important quantities of oil & gas have accumulated. In Saudi Arabia the faunal remains and the geological features encountered are both characteristic of terrestrial environments of deposition. A gradual change, however, is noticed some distance south and west of the Qatar-Saudi Arabia border where a marine influence becomes apparent. In Qatar, all terrestrial influences have disappeared, except may be in the uppermost Abu Samrah Member at some locations to the south. The shallow marine environment of the Dam in Qatar is demonstrated by all the characteristic geological features (beachrocks, ooids, stromatolites, crossbeds, etc…) and faunal & floral remains (marine mammals, mollusks, echinoderms, fish, arthropods, bryozoa, corals, etc…) that it left behind. It is hoped that the fossil enthusiasts will be pleased with this new publication. It offers several new localities to visit that can make for few interesting weekends of discovery and be used by the reader as points to start his own exploration of the Dam Formation. The author, in the meantime, will probably continue investigating the areas that were least explored for this document. Indeed, in the next year or so, we expect to look at areas 4, 5, 6 and 7 in more details and update (or use addendum) the present document with new uploads to the website. With regards to Area 8, we can only hope that one day we will be granted access to it; however, for the time being, this hope is very faint. Lastly, we would like to visit the Ishat Island to complete our study of the Dam Formation over accessible areas in Qatar but unfortunately, so far it has not been possible to find a boat ride for a period of one day or two over a weekend. We would ask that if there is somebody out there with enough boating experience and an interest in geology/fossils willing to share a day/weekend of adventure with me to please let me know On this note, I leave you. Wishing you all several enjoyable days of discoveries in this beautiful part of the world Jacques LeBlanc [email protected]

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9.0 - References Abu-Zeid, M. and H. Khalifa, 1983. Sedimentological and paleoenvironmental aspects of the Miocene succession in Jebel Nakhash, Qatar, Arabian Gulf. Neues Jahrbuch fur Geologie und Palaontologie Monatshefte, v. 7, p. 334-399. Ahlbrandt Thomas S., Fryberger Steven G. (1981). Sedimentary features and significance of interdune deposits. In: Recent and ancient nonmarine depositional environments: Models for exploration. Society of Economic Paleontologists and Mineralogists. Special Publication No. 31. Al Bowardi Mohammad et al (2005). The Emirates; a Natural history. Published with the support of: The Environment Agency, Abu Dhabi, (previously known as ERWDA), Al-Enezi , Saleh Ben Sfoog ben Marzoog (2006). Comparison of recent and Miocene foraminifera from Saudi Arabia. King Fahd University of Petroleum and Minerals. 156 pages. Mater thesis. https://eprints.kfupm.edu.sa/10564/ Al-Husseini, M.I. 2008. Middle East Geologic Time Scale. GeoArabia, v. 13, no. 4, p. 11 and 185188 (with 3 charts) http://www.gulfpetrolink.net/mepr/StratNoteMEGSindex.htm Al-Saad, H. and M. I. Ibrahim (2002a). Stratigraphy, Micropaleontology, and Paleoecology of the Qatar Miocene Dam Formation, Qatar. GeoArabia, v. 7, no. 1. Al-Saad Hamad, Nasir Sobhi and Sadooni Fadhil (2002b). Stratigraphy and sedimentology of the Hofuf Formation in the State of Qatar in relation to the tectonic evolution of the East Arabian Block. N. Jb. Geol. Palaont. Mh., Vol. 7, Pgs 426-448 Al Sharhan A.S., Nairn A.E.M. (1995). Tertiary of the Arabian Gulf: sedimentology and Hydrocarbon potential. Palaeogeography, Palaeoclimatology, Palaeoecology. Volume 114, Pages 369-384 Al-Youssef, Mariam (2003). Mineralogy, Geochemistry and origin of Quaternary sabkhas in the Qatar Peninsula, Arabian Gulf sabkha, PhD dissertation Southampton University, 438 pp. Al-Youssef Mariam , Stow Dorik A. V. , West Ian M. (2006). Salt lake area, northeastern part of Dukhan Sabkha, Qatar. In: Sabkha Ecosystems, Springer Netherlands, Volume 42. Pages 163-181. http://www.springerlink.com/content/q87u45551q694870/ Alles David L. (2006). Stromatolites. 28 pages. http://fire.biol.wwu.edu/trent/alles/Stromatolites.pdf Babikir A. A. A., C. C. E. Jackson (1983). Ventifacts distribution in Qatar. In: Earth Surface Processes and Landforms. Volume 10 Issue 1, Pages 3 - 15 http://www3.interscience.wiley.com/journal/112716092/abstract Butler Godfrey P. (in the 1990’s but exact year unknown). Holocene gypsum and anhydrite of the Abu Dhabi sabkha, Trucial coast: an alternative explanation of origin. [the publication type is unknown, however Mr. Butler worked for Esso in Houston, Texas] Cavelier Claude (1970a): Geologic description of the Qatar Peninsula (Arabian Gulf). Publ Government of Qatar, Dept of Petroleum Affairs [39 pp]. http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) Cavelier Claude (1970b). Geological survey and mineral substances exploration in Qatar. Bureau de Recherches geologiques et minieres. Cavelier Claude (1974). Le tertiaire du Qatar en affleurement. In : ASIE, Volume III, Fascicule 10 b 3. Union Internationale des sciences geologiques (1975) Dill, H.G. R. Botz, R., Z. Berner, Z., D. Stüben, D., Nasir S., and H. Al-Saad, H., (2005). Sedimentary facies, mineralogy, and geochemistry of the sulphate-bearing Miocene Dam Formation in Qatar. Sed. Geology, 174/1-2, 63-96. www.sciencedirect.com or www.geo.edu.ro/~sedim/Cursuri/Petr-sed-Tehn/2005-174-63.pdf Dill, H.G. and Friedhelm Henjes-Kunst (2007): Strontium (87Sr/86Sr) and calcium isotope ratios (44Ca/40Ca-44Ca/42Ca) of the Miocene Dam Formation in Qatar: tools for stratigraphic correlation and environment analysis. GeoArabia, Vol. 12, No. 3 El-Kassas I.A., (1992). A geostatistical study of gamma radioactivity at some anomalous localities in Qatar Peninsula, Arabian Gulf. J. King Saud University Volume 4 Science (1) p. 101-112 http://digital.library.ksu.edu.sa/V4M196R586.pdf Galil, B.S. 2006 Contributions to the knowledge of Leucosiidae VI. Soceulia gen. nov. (Crustacea: Brachyura). Zool. Med. Leiden 80(6):71-79. Glennie Kenneth W. (2005). The Desert of Southeast Arabia. GeoArabia Special Publication; Hardbound, 215 pages, over 200 colored illustrations, photos and satellite images. ISBN 99901-0489-1. http://www.gulfpetrolink.net/publication/sp.htm Hewaidy, A., 1991. Contribution to the stratigraphy of Miocene sediments in Qatar. Middle East Research Center, Ain Shams University, Egypt, Earth Science Series, v. 5, p. 160-170. Hilmy E.M., Abu Zeid M.M., & Al-Kuwari A. (1987). Petrography and sedimentology of the Miocene argillaceous rocks in Qatar, Arabian Gulf. – M.E.R.C Ain Shams Univ. Earth Sci. Ser. I: 169-179 Hunting Geology and Geophysics Limited (1983). Geological interpretation of digitally enhanced Landsat Imagery of Qatar. Project No. 220224. Government of Qatar, Industrial Development Technical Centre. Irtem, O., 1986. Miocene Tidal Flat Stromatolites of the Dam Formation, Saudi Arabia. King Fahd university. Petroleum minerals, res. inst., Dhahran.. Arabian Journal of Science and Engineering, v. 12, no. 2, p.145-153. http://cat.inist.fr/?aModele=afficheN&cpsidt=8195473 Johnson J.A.D, Storey M.W (March 1971). (H/109.672/20281)

Field Survey in Qatar, 15th – 25th March 1971.

Jones, R. W., and Racey A., 1994, Cenozoic Stratigraphy of the Arabian Peninsula and Gulf, in Simmons, M. D. ed. Micropaleontology and hydrocarbon exploration in the Middle East. Chapmon and Hall, pp. 273-303. Kendal C.G.S.C (2005). A series of online PowerPoint presentation at http://strata.geol.sc.edu/

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The Miocene Guide of Qatar, Middle East (Dam Formation) Khalifa, H. and M. Mahmoud, 1993. New occurrence of algal stromatolites and benthic Foraminifera from the Miocene of Al-Nakhsh area, southwest Qatar Peninsula: Implication on their palaeoenvironmental meaning. Arabian Gulf Journal of Science research, v. 11, no. 3, p. 325-338. Kier, Porter M. (1972): Tertiary and Mesozoic Echinoids of Saudi Arabia. Smithsonian contributions to paleobiology, No. 10 http://www.sil.si.edu/smithsoniancontributions/Paleobiology/ LeBlanc J. (2008). A Fossil Hunting Guide to the Tertiary Formations of Qatar, Middle-East. http://leblanc.jacques.googlepages.com/fossilhome Logan, B.W., Rezak, R., Ginsburg, R.N. 1964. Classification and environmental significance of algal stromatolites. J. Geol., 72, 62-83. LÓPEZ-ANTOÑANZAS, R. 2004. Neogene Ctenodactylidae, Thryonomyidae, and Zapodidae (Rodentia) from the Middle East: systematics, phylogeny, biostratigraphy, palaeogeography, and palaeoecology. Unpublished PhD thesis, Muséum national d’Histoire naturelle, Paris, 323 pp. LÓPEZ-ANTOÑANZAS, R, Sevket Sen 2004. Ctenodactylids from the Lower and Middle Miocene of Saudi Arabia. Palaeontology, Vol 47, Part 6. Pgs 1477-1494 Martin Joel W., Davis George E. (2001). An updated classification of the recent Crustacea. http://web.vims.edu/tcs/LACM-39-01-final.pdf Nguyen NGOC-HO (2003). European and Mediterranean Thalassinidea (Crustacea, Decapoda). ZOOSYSTEMA • 25 (3) Publications Scientifiques du Muséum national d’Histoire naturelle, Paris. www.zoosystema.com or http://decapoda.nhm.org/pdfs/20428/20428.pdf Otero Olga, Gayet Mireille (2001). Palaeoichthyofaunas from the Lower Oligocene and Miocene of the Arabian Plate: palaeoecological and palaeobiogeographical implications. Palaeogeography, Palaeoclimatology, Palaeoecology 165, 141–169 Peter C. K. (1985). Supratidal and lagoonal carbonate models in the Arabian Gulf. Robertson Group Philby, H. St. J. (1933). The Empty Quarter. 433 pages. London Powers R.W., L.F. Ramirez, C.D. Redmond, E.L. Eleberg, Jr. (1966). Geology of the Arabian Peninsula, Sedimentary Geology of Saudi Arabia, United States Geological Survey Professional Paper 560D, 147 pages Prothero and Schwab (year unknown). Lecture 9: THE BEACH. http://pkukmweb.ukm.my/~kamal/sedimentologi/pantai-1.pdf Puls Dave, Jameson Jeremy, Kozar Mike (Nov 2008). Miocene Dam Formation; Miocene outcrop description exercise. Part of a carbonate workshop sponsored by ExxonMobil in Qatar. Puls David D., Jameson Jeremy, Kozar Mike, Al-Ansi Hussain, LeBlanc Jacques (2009). The Dukhan Sabkha: A Modern Analog for the Arab C Carbonate Reservoir, Dukhan Field Integrated Study, Qatar. International Petroleum Technology Conference (IPTC), Doha, Qatar (In Press: to be presented in December 2009). IPTC paper 13629

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Sedimentary Environments and facies.

Blackwell Scientific

Roman, J. 1976. Echinides éocènes et miocènes du Qatar (Golfe Persique). Ann. Paleont. Invertebr., 62, 49–85. Schreiber B. Charlotte, Lugli S., Babel M. (2008). Evaporites through space and time. Geological Society of London. Special paper 285. Seilacher Adolf (2007). Trace fossil analysis. 238 pages. ISBN-13, 978-3-540-47225-4 Springer Berlin Heidelberg New York Seltrust Engineering Limited (1980). Qatar Geological Map: explanatory booklet Shearman D.J. (1983). Syndepositional and diagenetic alteration of Primary gypsum into anhydrite. Sixth international symposium on salt; Volume 1. Salt Institute. Shinn Eugene A. (2004). The Mystique of Beachrock. http://mgg.rsmas.miami.edu/rnggsa/shinnfinal.pdf Sugden W. Standring A.J. (1972). Stratigraphic lexicon: Qatar Peninsula. In : ASIE, Volume III, Fascicule 1O b 3. Union Internationale des sciences geologiques (1975) Tayyib Mohammed A. (2007). Depositional setting impact on the Portland cement production quality of the Dam Formation, Saudi Arabia. Thesis of Graduate Studies; King Fahd University of Petroleum & Minerals. 144 pages Thomas H., Sen S., Khan M., Battail B, and Ligabue G.. (1982). The Lower Miocene Fauna of AlSarrar (Eastern Province, Saudi Arabia). Atlal 5(3a):109-136 [A. Turner/H. O'Regan/H. O'Regan] Thralls, H. W. and R.C. Hasson (1956). Geology and oil resources of eastern Saudi Arabia. 20th International Geology Congress, Mexico and Symposium sobre Yacimentos de Petroleum and Gas, V. 2, p. 9-32. Tleel, J.W. (1973). Surface Geology of the Dammam Dome, Eastern Province, Saudi Arabia. American Association of Petroleum Geologists Bulletin, v. 57, no. 3, p. 558-576. Weijermars Ruud (1999a). Quaternary Evolution of Dawhat Zulum (Half Moon Bay) Region Eastern Province, Saudi Arabia. GeoArabia, Vol. 4, No. 1. Weijermars Ruud (1999b). Surface Geology, Lithostratigraphy and Tertiary Growth of the Dammam Dome, Saudi Arabia: A New Field Guide. GeoArabia, Vol. 4, No. 2 Whybrow, P.J. (1987a). Miocene geology and palaeontology of the United Arab Emirates and the State of Qatar (Arabian Gulf): the closure of Tethys and mammal `migrations’ between Afroarabia and Eurasia. M.Phil Thesis. Reading University, Reading. 136 pp. Whybrow, P.J. (1987b). Miocene geology and palaeontology of Ad Dabtiyah, Saudi Arabia. Bulletin of the British Museum (Natural History), Geology. Vol 41 No 4 29 Ziegler, M. A. (2001). Late Permian to Holocene paleofacies evolution of the Arabian Plate and its hydrocarbon occurrences: GeoArabia, v. 6, pp. 445-504. http://leblanc.jacques.googlepages.com/fossilhome

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10.0 - Recommended Literature General Al-Hajari Saif (1990). Geology of the Tertiary and its influence on the Aquifer System of Qatar and Eastern Arabia. University of South Carolina. Degree of Doctor in Philosophy in the Department of Geological Sciences. 250 pages Andrew Peters, Hamilton W. R., Whybrow P. J. (1978). Dryopithecines from the Miocene of Saudi Arabia. Nature 274, 249 - 251 (20 July 1978); http://www.nature.com/nature/journal/v274/n5668/abs/274249a0.html Bell R.T. (1996). Evaporites; in “Geology of Canadian Mineral Deposit Types. Geological Survey of Canada, Geology of Canada. No. 8, p. 121-127. Bibi Faysal, Shabel Alan B., Kraatz Brian P., Stidham Thomas A. (2006). New fossil ratite (Aves: Palaeognathae) eggshell discoveries from the Late Miocene Baynunah formation of the United Arab Emirates, Arabian Peninsula. Palaeontologia Electronica. http://palaeo-electronica.org Chan, Marjorie A. and Parry, William T. (year unknown but past 2001). Rainbow of Rocks. Mysteries of Sandstone Colors and Concretions in Colorado Plateau Canyon Country. Dept. of Geology and Geophysics, 135 S. 1460 E. - University of Utah, Salt Lake City, UT 84112-0111. http://geology.utah.gov/online/pdf/pi-77.pdf Dill, Harald G.: Sobhi Nasir and Hamad Al-Saad (2003). Lithological and structural evolution of the northern sector of Dukhan anticline, Qatar, during the early Tertiary: with special reference to sequence stratigraphic bounding surfaces GeoArabia Volume 8, Number 2, P 201-226 Dill, Harald G, Friedhelm Henjes-Kunsta, Zsolt Bernerb and Doris Stübenb (2008). Miocene diagenetic and epigenetic strontium mineralization in calcareous series from Cyprus and the Arabian Gulf: Metallogenic perspective on sub- and suprasalt redox-controlled base metal deposits. Journal of Asian Earth Sciences, Volume 34, Issue 4, 30 April 2009, Pages 557-576. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VHG-4TG35P71&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1 &_urlVersion=0&_userid=10&md5=a9ff730647e2d39c4509be6acc85ca1d Dill, Harald G.; Kaufhold, Stephan (2008). Mineralogical and lithofacies-controlled variation of palygorskite in Neogene siliceous-calcareous coastal deposits in geodynamically stable (Qatar) and mobile settings (Uzbekistan). Neues Jahrbuch für Mineralogie - Abhandlungen, Volume 185, Number 2, November 2008 , pp. 143-160(18). http://www.ingentaconnect.com/content/schweiz/njma/2008/00000185/00000002/art00003?token= 004f1655ba6c0b5c5f3b3b476754486b3c257b51766c5f3f4f582a2f433e402c3568263c2bfec9c Elliott Graham F. (1960). Brachiopodes tertiaire d’Arabie et de Syrie. Bulletin de la Societe Geologique de France; 7ieme Serie, Tome 2, Pages 152-156 Fleming C. A. (1981). A new grapsid crab from the Upper Miocene of New Zealand. Journal of the Royal Society of New Zealand. Vol 11, No. 2, pgs 103-108. Garcia-Guinea J, Morales S, Delgado A, Recio C, Calaforra JM. Formation of gigantic gypsum crystals. J Geol Soc (Lond) 2002;159:347– 50.

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The Miocene Guide of Qatar, Middle East (Dam Formation) Hamilton W.R., Whybrow P.J., McClure H.A (1978). Fauna of fossil mammals from the Miocene of Saudi Arabia. Nature 274, 248 - 249 (20 July 1978); http://www.nature.com/nature/journal/v274/n5668/abs/274248a0.html Henson, F.R.S. (1950). Middle Eastern Tertiary Peneroplidae (Foraminifera). With Remarks on the Phylogeny and Taxomony of the Family. Wakefield, England, West Yorkshire Printing Co., 70 p. Houbolt, J.J.H.C., 1957. Surface Sediments of the Persian Gulf Near the Qatar Peninsula. The Hague, Netherlands, Mouton and Co., 113 pp. Kendall AC. Evaporites. In: Walker RG, James NP, editors. Facies models-response to sea level change. Geol Assoc Canada; 1992. p. 375– 409. M. M. Ashour (1987). Remote Sensing of Desert Sediments: Grain Size, Process and Dune Environment: Surficial deposits of Qatar Peninsula. Geological Society, London, Special Publications; v. 35; p. 361-367; DOI: 10.1144/GSL.SP.1987.035.01.24 http://sp.lyellcollection.org/cgi/content/abstract/35/1/361 Scoffin TP. An introduction to carbonate sediments and rocks. Glasgow. Blackie; 1987. [274 pp]. Smout, Alan Hilder (1954). Lower Tertiary foraminifera of the Qatar Peninsula. British Museum (Natural History). Turner, RJ. (2005). Beachrock, in Schwartz, ML, ed., Encyclopedia of Coastal Science. Kluwer Academic Publishers, The Netherlands. Pp. 183-186. Warren J.K., Kendall C.G. ST. C. (1985). Comparison of sequences formed in Marine Sabkha (subaerial) and salina (subaqueous) settings – Modern and Ancient. AAPG bulletin V. 69 No. 6, Pgs 1013-1023. Warren JK. Evaporites—their evolution and economics. Oxford. Blackwell; 1999. [438 pp]. Whybrow P. J., Hill A. (1999). Fossil vertebrates of Arabia - with emphasis on the Late Miocene faunas, geology and paleoenvironments of the Emirate of Abu Dhabi, United Arab Emirates Wright VP. A revised classification of limestones. Sediment Geol 1992;76:177–85.

Stromatolite Literature J.D. Aitken, 1967. Classification and environmental significance of cryptalgal limestones and dolomites, with illustrations from the Cambrian and Ordovician of SW Alberta. J. of Sedimentary Petrology, 37, 4, 1163-1178. T.D. Brock, 1976. Environmental microbiology of living stromatolites. In M.R. Walter, éd.: Stromatolites. Developments in Sedimentology, 20, Elsevier, 141-148. C.D. Gebelein, 1976. The effects of the physical, chemical and biological evolution of the earth. In M.R. Walter, éd.: Stromatolites. Developments in Sedimentology, 20, Elsevier, 499-515 S. Golubic, 1976. Organisms that build stromatolites In M.R. Walter, éd.: Stromatolites. Developments in Sedimentology, 20, Elsevier, 113-126.

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The Miocene Guide of Qatar, Middle East (Dam Formation) S. Golubic, 1976. Taxonomy of extant stromatolites-building cyanophytes In M.R. Walter, éd.: Stromatolites. Developments in Sedimentology, 20, Elsevier, 127-140. Hofmann H.J (1969). Attributes of stromatolites. Paper 69-39. Geological survey of Canada. 33 pages L.A. Hardie & R.N. Ginsburg, 1977. Layering: the origin and environmental significance of lamination and thin bedding. In L.A. Hardie, éd.: Sedimentation on the modern carbonate tidal flats of Northwest Andros Island, Bahamas. The John Hopkins University Press, 50-124. C.G. Kendall & Sir P.A. d'E. Skipwith, 1968. Recent algal mats of a Persian Gulf lagoon. J. of sediment. Petrology, 38, 4, 1040-1058. B.W. Logan, R. Rezak & R.N. Ginsburg, 1964. Classification and environmental significance of algal stromatolites. J. of Geology, 72, 1, 68-83. R. Park, 1976. A note on the significance of lamination in stromatolites. Sedimentology, 23, 3, 379393. P.E. Playford & A.E. Cockbain, 1976. Modern algal stromatolites at Hamelin Pool, a hypersaline barred basin in Shark Bay, Western Australia In M.R. Walter, éd.: Stromatolites. Developments in Sedimentology, 20, Elsevier, 389-411. B.H. Purser, 1980. Sédimentation et diagenèse des carbonates néritiques récents. Tome 1: les éléments de la sédimentation et de la diagenèse. Ed. Technip, 367 pp. B.H. Purser, 1983. Sédimentation et diagenèse des carbonates néritiques récents. Tome 2: Les domaines de sédimentation carbonatée néritiques récents; application à l'interprétation des calcaires anciens. Ed. Technip, 389 pp. E.A. Shinn, 1983. Tidal flat. In P.A. Scholle, D.G. Bebout, C.H. Moore, eds.: Carbonate depositional environments, AAPG Mem., 33, 708 pp.

On Gypsum, selenite and crystals (Recommended by Dr. Richard T. Bell, of the Geological Survey of Canada) Bain, Roger J (1990) GSA v 18, pp 447-450 McBride, Earle F ( 1991) AAPG v 75 - He shows some up to 2' ( gypsum, selenite and crystals). Schrieber, Lugli and Babel, "Evaporites Through Space and Time"; Geol Society of London Special Paper 285 (2008). Anything by Dave Kinsman is very useful.

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Websites Since these pages are out of our control, there is no guarantee that they will always be accessible. • • • • • • • • • •

http://decapoda.nhm.org/ www.wikipedia.org www.sirenian.org The oldest sirenian: http://news.nationalgeographic.com/news/2001/10/1010_jamaicaseacow.html Qatar – Sabkha, Salt lakes and other desert environments: http://www.soton.ac.uk/~imw/Qatar-Sabkhas.htm The Qatar Natural History Group: http://www.qnhg.org/ The Qatar Geological Society: http://www.qgeosoc.com/ http://strata.geol.sc.edu The management of gypsiferous soils: http://www.fao.org/docrep/t0323e/t0323e00.htm#Contents http://www.crienterprises.com/Edu_Evap_Coastal_Sabkha.html

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APPENDICES 11.1 - A brief introduction to Carbonates For the people unfamiliar with carbonates, we see it appropriate to summarize very briefly the conditions under which they form and how they get preserved. Carbonate sediments accumulate in areas of high biological activity and low terrigenous input. Although more common in shallow tropical seas, they are not restricted to these environments and quite extensive accumulations occur in temperate latitudes. The vast majority of primary carbonate sediment is produced biogenically, usually within the basin deposition. This contrasts strongly with clastic sediments which usually originate outside the basin of deposition. Inorganic formation of carbonates is of relatively minor importance. The five types of carbonates are Limestone, Dolomite (or dolostone), Chert, evaporites and coal. Carbonates sediments consist of grains and mud. (Peter, 1985) •

Grains can be conveniently subdivided into skeletal and non-skeletal types

Table 11-1: Grain subdivisions Major Types of Skeletal grains (from biological skeletons) Bivalve Gastropod Brachiopod Coral Bryozoan Stromatoporoid Algal debris Echinoderm Foraminifera

Non-Skeletal grains Ooids Pisoids Oncoids Intraclasts Lithoclasts Pellets Peloids

The skeletal grain types are the remains of organisms which secrete an external or internal calcareous skeleton. The type of skeletal grain closely relates to the ecologic environment and is an important indicator of depositional conditions. For example, reef building corals are restricted to specific conditions (tropical marine areas, shallow clear waters, etc..). Non-skeletal grain types form in various ways. Ooids and pisoids are aragonite concretions which form in agitated shallow tropical waters. Oncoids are grains coated in blue green algae which also form in shallow tropical waters. Intraclasts and lithoclasts are re-eroded fragments of already deposited lime sediments and limestone. Pellets are excreted material from many animals (gastropods, worms, etc..), and peloids are rounded lumps of carbonate mud of indeterminate origin. •

The other major constituent of lime sediments is mud.

This may, in part, form by direct precipitation of aragonite needles from seawater, but by far the majority of lime mud sediment forms from the mechanical abrasion or chemical breakdown of skeletal organisms, particularly green algae

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Figs 11.1.1 to 11.1.5: Environments of deposition, textures and components of carbonates (http://strata.geol.sc.edu ) http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) Sedimentary structures These are the “signature” of the depositional environments A. Bedding – the most common characteristic of sedimentary rocks 1. Layers of sedimentary rock – rocks tend to break along these planes 2. Thickness – thin, medium, coarse, massive (no bedding) 3. Types (see images below) Fig 11.1.6: Some examples of types of bedding

A. Horizontal. Laminated layers of siltstone B. Cross bedding. In the case above they are and shale (A1_2132) which reflect intermittent trough cross-beds reflecting scour and fill in a settling of particles from suspension. fluvial deposit. (A1_7006)

C. Graded bedding (A1_8001). Vertical D. Ripple marks or ripple laminations decrease of grain size within a layer; pebbles at (A1_3024) the bottom and smaller grains at the top. B. Stratigraphy – layers of different rock types 1. Indicates changes in sedimentary environment (Ex.: limestone over a shale) 2. Fossils – preserved sedimentary rocks, indicate evolution of organisms C. Diagenesis 1. Transformation from sediment to sedimentary rock a. Burial – compaction – cementation – lithification Diagenesis is any chemical, physical, or biological change undergone by a sediment after its initial deposition and during and after its lithification.

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The Miocene Guide of Qatar, Middle East (Dam Formation) These changes happen at relatively low temperatures and pressures and result in changes to the rock's original mineralogy and texture.

Environment of deposition A) Supratidal or Sabkha (fig 11.1.7): A salt encrusted plain which lies above normal high tide but within the range of high storm tides. The sediments consist of often pelleted carbonate muds with accumulations of bioclastic material. They are the result of high storm tides and onshore winds periodically flooding the supratidal plain such that sediments derived from the lagoon are redeposited. The characteristic feature of this environment is the development of early diagenetic anhydrite and dolomite replacing the host carbonate sediment. Typically, the anhydrite exhibits a nodular or chicken-wire texture [see the section on chicken-wire below]. (Peter, 1985) B) Intertidal: The zone between normal low tide and normal high tide. These deposits are particularly variable, depending on the angle of the slope, degree of protection, etc. Where the intertidal zone is a gently sloping area, then a mucilaginous spread of algal mats develops. The algae trap fine sediments and produce a laminated deposit. The intertidal zone is cut by tidal channels which over a period of time may migrate across the mud flats, leaving fining upwards sequences with basal scours and lag deposits Where the intertidal zone is steeper, a beach face, often capped by a beach ridge, may developed. The sediments that accumulate are cross bedded carbonate sands (bioclastic, peloidal, oolitic), although the cross bedding is frequently destroyed by bioturbation. Intertidal sediments may also be affected by “diagenetic” processes. Where carbonate sand is the dominant sediment, the carbonate grains may be cemented by aragonite to give a beachrock. Boring, and reworking of this material to produce lithoclasts, is common. The cemented intertidal rock may exhibit polygonal cracking and be heaved into tepee structures. The slabs forming the tepees may themselves be reworked. (Peter, 1985) C) Subtidal: Consisting of the zone below normal tide levels. It includes a range of environments from sheltered lagoon to open marine shelf. The typical lagoonal sediments comprise soft mud, which is commonly pelleted, with varying amounts of skeletal grains. In the highly saline restricted parts of lagoons, the sediments are homogeneous or finely laminated, with local development of evaporite minerals. Where the waters are less saline, burrowing organisms thrive and so the laminations are destroyed by bioturbation. Subtidal currents are often active both within and between channels, such that carbonate sand bodies consisting of winnowed peloids and micritised skeletal grains are developed. Algal mats also grow in subtidal conditions but are commonly destroyed by grazing gastropods. (Peter, 1985)

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http://www.crienterprises.com/Edu_Evap_Coastal_Sabkha.html

Fig 11.1.7: Sketch showing the Sediment and evaporite distribution within a typical Marine Sabkha http://strata.geol.sc.edu

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Fig 11.1.8: Outcrop and pit description form (Provided by Dr. Jeremy Jameson) During field work, all the carbonate characteristics described in the previous pages are described by the geologist on forms (fig. 11.1.8) specially designed to gather as much information as possible on all studied outcrops before it is compiled and integrated in the research. http://leblanc.jacques.googlepages.com/fossilhome

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11.2 - Little known facts about the Dam & Hofuf formations 11.2.1 – Ventifacts distribution in Qatar Ventifacts (Figs 11.2.1 to 11.2.5) are pebbles which have developed one or more flattened, often highly polished facets as a result of windblown sand abrasion. A Dreikanter is a ventifact that exhibits a characteristic three-faced pyramidal shape. The word Dreikanter is a German word meaning "a three-sider". Other forms of ventifacts are the eikanter, with one or two facets and one ridge (crest), and the ridge-shaped or roof-shaped ventifact with two dominant facets. The conditions to form ventifacts are close to ideal when there is an adequate but a not too great supply of tough abrasives carried in strong winds across vegetation-free ground littered with relatively soft rock fragments. These conditions have been met in all of our eight (8) areas of investigation where pebbles of the Hofuf formation (LeBlanc, 2008) have sustain constant sand abrasion due to the high winds occurring in this flat and barren land. No matter where you go during your Dam Formation fossil hunting trips, you will undoubtedly walk on ventifacts. Babikir et al (1983), studied the ventifacts in Qatar and came up with the following conclusions: 1) Ventifact distribution in Qatar is directly related to the proximity of the Hofuf formation (within a distance of about 5 kms). 2) Higher areas have big gravel counts and a low ratio of ventifacts while the low-lying plains have small gravel counts and a higher ratio of ventifacts. 3) In certain areas “ventifact field” were found where the density of ventifacts was as high as 30 per m2. Many of the ventifacts in these fields were buried beneath the surface suggesting that the ventifaction predates the present site conditions. 4) Other high ventifact density areas were discovered where the ventifacts have collected in shallow depressions or hollows on the limestone plateaux. Water action has washed these ventifacts, a high proportion of which are dreikanters, into the hollows, where they have been partially buried in fine alluvial silts (Fig 11.2.1). The “ventifact graveyards” (Fig 11.2.6) are generally only a few metres wide but contain large numbers of fine specimens. Beautiful dreikanters were collected from the graveyards. The average size of the ventifacts from the graveyards is about double that of ventifacts from other areas. 5) Most of the ventifacts are between 2 and 5 cm in size with smaller (1-2 cm) quartz dreikanters rather commoner. Larger ventifacts are uncommon but more easily spotted because of their size. Several specimens up to 14 cm have been found. 6) Ventifacts have been observed in all stages of development from an initial abrasion of one facet with a slight but definite crest, to completely finished highly polished “Brazil nut” type dreikanters exhibiting near perfect symmetry. Petrographic studies performed by Al-Saad et al. 2002b on the Hofuf gravels indicate that the material (including the ventifacts) include igneous, metamorphic, sedimentary rocks and quartz. All types occur in about equal abundance. Igneous rocks pebbles consist mainly of rhyolite and granite whereas basalt is subordinate. The igneous rock pebbles are similar petrographically to those of the Arabian Shield. Pebbles of metamorphic rocks are biotite gneiss and metagreywacke, similar to the metamorphic rocks that outcrop in the Arabian Shield. Sedimentary pebbles consist mainly of micritic and biomicritic limestones similar to Mesozoic and Tertiary carbonates of the Arabian Peninsula.

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Fig 11.2.1: Ventifact graveyard (Babikir et al 1983).

Fig 11.2.3: Ridge-shaped or roof-shaped ventifact with two dominant facets

Fig 11.2.4: Dreikanters

Fig 11.2.2: Ventifact

Fig 11.2.5: Pyramid shaped ventifact

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Fig 11.2.6: The distribution of ventifacts in Qatar according to their concentration. Note that the grid used is not the Qatar National Grid (QNG).

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11.2.2 - Why is there contamination of sulphate in the Hofuf formation: the answer lies in the Dam formation The construction boom that Qatar has been experiencing since about 10 years ago has increased the demand for concrete as a building material. The two main components of concrete are limestone and sand. The limestone is extracted from the widespread Eocene Dammam formation, while the sand comes from the very restricted Pliocene Hofuf formation. With the rate at which the sand is extracted from the known areas of Hofuf accumulation, it would be normal to assume that the quarry operators will be faced soon with finding other alternate sources of sand. The decision for the timing of this replacement source will be based mainly on three factors: 1) Are there more available areas of Hofuf sand? To our knowledge, all the known economical occurrences of Hofuf accumulation have already been assigned to operators; these are currently producing as quickly as possible in order to meet the high demand. 2) The Hofuf is composed of layers of gravel and sand. While the Hofuf may have accumulated in some areas, it does not mean that the sand is present in all of them in economical quantities. 3) The third and most important factor is the quality of the sand. While the sand may have accumulated sufficiently in certain areas to make its exploitation economical, further testing of the material may reveal a very high content of contaminants such as sulphate (mainly) and chlorite (to a lesser degree). These contaminants may render uneconomical the production of a site at current market price. In the few paragraphs below, we wish to explain the reasons behind the contamination of the Hofuf sand over the Khashm Al-Nakhsh - Wadi Al-Huwaylah ridge; Wadi Al-Huwaylah being the northernmost area with Hofuf sand and which is currently exploited by QNCC. It is located south of the town of Umm Bab. Please refer to the schematic diagram in fig 11.2.7. When the Hofuf gravels and sands were being deposited from South to North during the Pliocene, it eroded the members of the Dam formation with a higher erosion rate towards the north; therefore, the underlying Dam formation is today thinner in the north than it is in the south. The green shale of the Lower Salwa member is one of the uppermost layer of the Dam formation in Wadi AlHuwaylah, while it is overlaid by the other members of the Dam in Khashm Al-Nakhsh. As it is illustrated in fig 11.2.8 below, the Middle and Upper Al-Nakhsh sub-members of the Dam formation contain high concentrations of sulphate due to the presence of the mineral gypsum (calcium sulphate dihydrate, with the chemical formula CaSO4·2H2O). Since these two submembers were deposited under supratidal (sabkha) conditions, they contain also other evaporitic minerals such as salt (Sodium chlorite, NaCl). During the few million years that followed the deposition of the Hofuf, the sulphate and chlorite contained in the gypsum and salts got dissolved gradually with the percolating rain water and contaminated the overlying Pliocene sands through capillary pressure (pink colour in fig 11.2.7). This process re-deposited the gypsum as hard crust at one or various levels within the Hofuf sand. To conclude, when the Hofuf formation is found laying directly over the Salwa & Abu Samrah Members and the Lower Al-Nakhsh sub-member (which contain no or very little evaporites/contaminants) the sands of the Hofuf will be of a much higher quality. In the case of the Khashm Al-Nakhsh - Wadi Al-Huwaylah ridge, we estimate that the Hofuf sand located between Khashm Al-Nakhsh and a point 9 kms north of it, will be either too contaminated or too thin to be exploitable economically with standard methods. http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.2.7: Schematic geological representation of the Wadi Al-Huwaylah – Khashm Al-Nakhsh ridge explaining the reasons for the higher contamination of the Hofuf formation to the south. Khashm Al-Nakhsh is located at 24.874561°N and 50.907466°E, while the QNCC sand quarry at Wadi Al-Huwaylah is located at 25.063715°N and 50.833411°E http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.2.8: Stratigraphic column showing the lithology, age and environment of deposition of the Dam Formation (Dill et al, 2007). Note the high content of sulphate (dark green) in the Middle Al-Nakhsh and the Upper Al-Nakhsh members. http://leblanc.jacques.googlepages.com/fossilhome

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11.3 – Glossary & Coordinates of the main geographical localities Abu Samrah Al Huriyah Al Kharrarah Al Nafkah Artiodactyl Benthonic

Calappa

Cement

Chelae Colloform

Concrete Doha Doline Dreikanter Dukhan Hazm Mashabiya or Hazm Mishabiyah Khashm Al Nakhsh Macrura nektonic Packstone

24.742065°N and 50.847311°E in Area 3 25.11667° N and 50.93333° N in Area 7 24.904440° N and 51.175000° E in Area 4 24.837854° N and 50.888772° E in Area 2 Any member of the mammalian order Artiodactyla, or even-toed ungulates, which includes the pigs, peccaries, hippopotamuses, camels, chevrotains, deer, giraffes, pronghorn, antelopes, sheep, goats, and cattle. It is one of the larger mammal orders, containing about 150 species. of or relating to or happening on the bottom under a body of water Genus of crabs known commonly as box crabs, or shame-faced crabs. The name box crab comes from their distinctly bulky carapace, and the name shame-faced is from anthropomorphising the way their chela (claws) fold in in front of their face, as if hiding it in shame. There are thirty nine generally recognised species in the genus. Taxonomic sources disagree on the number of species, with some sources classifying several species from the genus Cancer as Calappa. http://en.wikipedia.org/wiki/Calappa_(crab) A binder, a substance which sets and hardens independently, and can bind other materials together. Cements used in construction are characterized as hydraulic or non-hydraulic. The most important use of cement is the production of mortar and concrete. Concrete should not be confused with cement because the term cement refers only to the dry powder substance used to bind the aggregate materials of concrete. Upon the addition of water and/or additives the cement mixture is referred to as concrete, especially if aggregates have been added. A pincerlike claw of a crustacean such as crab A texture often found in certain types of mineral deposits, where crystals have grown in radiating and concentric manner A construction material composed of cement as well as other cementitious materials such as fly ash and slag cement, aggregate (generally a coarse aggregate such as gravel, limestone, or granite, plus a fine aggregate such as sand), water, and chemical admixtures. 25.313848° N and 51.526980° E Depression formed as underlying limestone bedrock is dissolved by groundwater. Geologically speaking, it is the step before a sinkhole is created. A Dreikanter is a ventifact that exhibits a characteristic three-faced pyramidal shape. They typically form in desert or periglacial environments from the action of wind erosion. The word Dreikanter is a German word meaning "a three edger." 25.418318° N and 50.784015 E 24.737246°N and 50.895512° E in Area 3 24.875016° N and 50.903403° E in Area 1. Spelled “Khazm Al Nakhsh” in some publications A subdivision of decapod Crustacea, having the abdomen largely developed. It includes the lobster, prawn, shrimp, and many similar forms. The collection of marine and freshwater organisms that can swim freely and are generally independent of currents, ranging in size from microscopic organisms to whales Contains lime mud, but is grain supported. http://en.wikipedia.org/wiki/Packstone http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) "Odd-toed" or "odd-hoofed" mammals make up the Perissodactyla. Like the "even-toed" Artiodactyla, perissodactyls are unguligrades; that is, they walk on the terminal bones of the toes and have enlarged toenails forming hoofs. Unlike artiodactyls, perissodactyls either walk on three toes (like rhinos, tapirs, many extinct horses, and other extinct groups) or on a single toe (like recent horses). Perissodactyla Only seventeen species of perissodactyls remain on the Earth today, a shadow of the group's former glory. Perissodactyls were once much more diverse, including the enormous horned brontotheres, the bizarre browsing, clawed chalicotheres, and the largest land mammal of all time, the Eocene Indricotherium (formerly known as Baluchitherium). It stood five meters (over sixteen feet) tall at the shoulder. The part of a lake bottom covered by water shallow enough to permit the growth Phytal zone of rooted plants. 24.673075° N and 50.859539° E (Elevation: 57 m) in Area 3. Hill officially Qarn Abu recognized since 2003 as one of the points along the Saudi Arabia and Qatar Wail border Creeping or crawling Reptant Sawdaa 24.568333° N and 51.068333° E Natheel Sinkholes vary greatly in area and depth and may be very large. The two main varieties are those caused by the collapse of a cavern roof, and those caused by the gradual dissolving of rock under a soil mantle. Collapsed sinkholes generally have Sinkhole steep rock sides and may receive streams that then flow underground. Soilmantled sinkholes are generally shallower; they may become clogged with clay and hold a small lake. Rock material formed from consolidated mud or sediment that filled a hollow organic structure, such as a fossil shell. The fossil formed after dissolution of the Steinkern mold. Also known as endocast; internal cast. An unstable mineral, a hydrous chloride of calcium and magnesium with formula: Tachyhydrite CaMg2Cl6·12H2O. It is a rare component of marine evaporite salt deposits. Upon exposure to moist air it rapidly deliquesces and dissolves. One of three infraclasses in class Actinopterygii, the ray-finned fishes. This diverse group, which arose in the Triassic period, includes 20,000 extant species Teleosts in about 40 orders; most living fishes are members of this group. The other two infraclasses are Holostei and Chondrostei. Ţi`s al 25.009702° N and 51.043668° E just east of Area 7 Kir`ānah Ţiwār al 24.805560° N and 51.093330° E in Area 4 Huraythī To reduce to fine particles or powder by rubbing, grinding, bruising, or the like; Triturate pulverize 25.203187° N and 50.804425° E near northern portion of Area 6 Umm Bab Rocks that have been abraded, pitted, etched, grooved, or polished by wind-driven sand or ice crystals. These geomorphic features are most typically found in arid environments where there is little vegetation to interfere with aeolian particle Ventifact transport, where there are frequently strong winds, and where there is a steady but not overwhelming supply of sand. Elongated landform of weakly cemented rock that has been sculpted by the wind. Yardang Commonly found in groups. A flat-topped outcrop whose long axis is parallel to, and was sculpted by, the Zeuge / prevailing wind. Rather like a yardang but with a hard cap-rock. Plural Zeugen Zeugen http://leblanc.jacques.googlepages.com/fossilhome

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11.4 - How to load and use our geological mapping package in GoogleEarthTM

Fig 11.4.1: Once you have downloaded the KMZ file titled “2009_Dam Formation Study”, drag it to the “Temporary Places” folder in the pane on the left side of the GoogleEarthTM (GE) view as per image below. http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.4.2: The image will show eight empty areas, and the pane to the left will display in the “Temporary Places” folder eight sub-folders named Area-01 to Area-08. Each of these sub-folders can be expanded and their information viewed according to your selection (see next image) http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.4.3: Once Aera-01 has been expanded, more sub-folders appear. If you expand the folder “Area-01_Dill_Outline” and check the boxes next to its sub-folders, the black frame and blue line will appear as shown in the image. The black frame represents the area that Dill et al mapped in 2005 and 2007 while the blue line represents the cross-section that Dill et al used to come up with their stratigraphic column of the Dam Formation in 2005 and 2007. The red frame is our area 1 which we have mapped and investigated. You can elect to leave any of these frames and lines on or off just by checking or un-checking the small boxes to the left of each folder, placemark or GPS point (as will be seen below) http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.4.4: If the “Area-01_Mapping” folder is expanded and completely selected, our geological mapping of the Dam will appear. The colours used for contouring are detailed in chapter “F” at the beginning of this document. Each line can be turn on or off as required by just checking on or off the small boxes next to the appropriate sub-folders http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.4.5: If the “Area-01_GPSwayPoints” folder is expanded and completely selected, it will display all our GPS points in our Area 1. The subfolders under this folder, and the GPS points they contain, are named according to the naming convention described in chapter “F” at the beginning of this publication http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.4.6: If one of these points is clicked on once (either directly on the satellite picture or in the pane to the left) a geological and/or a paleontological description of the location can be viewed The above steps were just a quick way to familiarize you with how to navigate through our geological investigation of the Dam. Repeat these steps for the other areas in order to view all the information. Remember that only Areas 1 & 2 were mapped but Areas 3 to 7 were visited and some interesting points were also located. Area 8 was not visited because it requires a special permission that was not sought. http://leblanc.jacques.googlepages.com/fossilhome

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11.5 The Rock-Carvings at Jarr Umm Tuwaim The article below deals with the archeological site of Jarr Umm Tuwaim at our locality A5_2001. It was originally written in 1998 by Mrs. Frances Gillespie as a Qatar Natural History Group article and is here reproduced in its entirety with some changes as requested by the author. The changes (and additional notes) have been outlined in blue. We did not have access to the original color pictures therefore we used the black & white copies that we had. You can look at our own pictures (6) in our photo album If you have any questions in relation to this article, please contact Mrs. Gillespie directly.

A STUDY OF SOME BEDOUIN ROCK-CARVINGS IN SOUTH-WEST QATAR Frances Gillespie APRIL 1998 [email protected] Qatar Natural History Group REPORT ON THE SURVEY AT JARR UMM TUWAIM MARCH 1998 On 27-28 March 1998, members of the Qatar Natural History Group participated in a comprehensive field survey of a circular area of approximately 3 km radius, centred on Jarr Umm Tuwaim. This is an isolated single outcrop of heavily-weathered limestone rising some 6 km from the desert floor at its higher, southern end, and honey-combed with large natural cavities, some of which have formed shallow caves under the rock and are used by camel herdsmen as shelters. The rock lies some 7.5 kms east of the coast, in an area known by some local informants as Wadi Al Hawolah. The map reference is 25 01. 606N 050 52. 706E. In February 1996 the Chairman of the NHG, John Bell, had first noted the presence of a variety of petroglyphs on the upper surface of the rock. A preliminary recording and photographing of the carvings was carried out in 1996. In the absence of any known local name the members of the NHG felt at liberty to give it the appellation “Bell Rock” for ease of reference, however it was later changed to Jarr Umm Tuwaim by the official archeological authorities of Qatar The survey, which was carried out by several teams, included a geological surface survey of the area, a flora and fauna survey and a look at possible archaeological sites in the area, plus a record of the carvings on the rock. To the best of our knowledge this has not previously been undertaken, and there is no reference to this particular set of rock-carvings by the Danish, British and French teams of archaeologists who conducted surveys between the mid-1950s and the end of the 1970s. The carvings are confined to an area at the southern end of the rock. A boulder bearing some carvings has broken off and lies on the slope below. The carvings consist: A) A variety of wasm [camel-brands]; B) Double rows of cup marks, often referred to by archaeologists as "game-boards"; C) Several single or paired cup marks; D) A single small, shallow oval pit. At the northern end of the rock we excavated a reservoir which was used for collecting rainwater. This will be described in detail later on. http://leblanc.jacques.googlepages.com/fossilhome

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Fig. 11.5.1: Jarr Umm Tuwaim archeological site. The site sits on the Miocene rocks of the Middle Salwa member of the Dam Formation (Colored geological map from Hunting, 1983)

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Fig 11.5.2: Jarr Umm Tuwaim with the “Mancala boards” and “Wasms” http://leblanc.jacques.googlepages.com/fossilhome

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Fig 11.5.3: Sketch plan of Jarr Umm Tuwaim

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The Miocene Guide of Qatar, Middle East (Dam Formation) Jarr Umm Tuwaim is a natural landmark visible from a considerable distance, which stands at a height of 59m above sea-level in an area of sand and gravel, dotted with "dreikanters" (multifaceted wind-etched pebbles) (see chapter 11.2) and supporting a variety of vegetation. On all sides of the Rock lie long, low, wind-scoured outcrops of limestone. An extensive search of these failed to reveal any other manmade markings. It seems that the superior height of Jarr Umm Tuwaim above the surrounding, otherwise rather featureless landscape made it a natural focal point for the pastoral peoples who have travelled this area for many centuries. The area is still used for camelgrazing. On the flat land to the east of Jarr Umm Tuwaim, at a distance of 200-500 m, were a number of grave sites (See locality “One pre-islamic grave” in our Google Earth file for Area 5): low cairns piled with rocks. These are presumed to be pre-Islamic as they are all orientated north-south. Puzzlingly, one grave has a distinctly "Islamic" look about it, being long and narrow with an upright head and footstone. More research needs to be done on these. We had understood that Islamic graves are always aligned east to west, but perhaps this is not always the case. A local man, who passed by while we were there, told us that there are many bedouin graves to the west of the Rock, but we have not yet located these. Located close to the Rock on its east side are two adjacent circles of stones, each about 3m in diameter. These might be the remains of burial cairns or possibly of some kind of structure. Again, only surmise is possible until such time as research and possibly excavation is undertaken by experts. Surprisingly, there is a total absence of pot-sherds around Jarr Umm Tuwaim. The presence of these might have yielded a clue as to the date of the carvings.

Rock-Carvings in Qatar The carvings on Jarr Umm Tuwaim must be evaluated within the wider framework of Qatari petroglyphs, two areas of which have been researched and documented. The rock-carving sites of Qatar, which bear many unique features, are all on low outcrops of limestone around the northern and eastern coasts of the country, between A1 Furaihah, a short distance north of Zubara Fort, and Al Wakra on the east coast, where the carvings occur on a large jebel south of the town. [Since 1991 this jebel has been enclosed by a security fence to protect the radar station on the rock, so the carvings are not now accessible to the public.] Without exception, the dozen or so rock-carving sites around the coast are all adjacent to, or within sight of the sea. This makes the carvings on Jarr Umm Tuwaim unique, in that they are located in the southwest, far from any other carvings, and are more than 7 km from the sea. Hitherto, the few studies carried out on rock-carving sites in Qatar had emphasized their association with sea-going peoples, and had noted the similarity of many of the carvings to those on coastal sites as far away as the north of Scotland! Clearly, in the light of our recent discoveries, this approach will need to be reconsidered.

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Fig 11.5.4: Carvings at the southern end of Jarr Umm Tuwaim

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The Miocene Guide of Qatar, Middle East (Dam Formation) The most varied and interesting of the petroglyphic sites is at Jebel Al Jusasiyah on the north-east coast, where in 1974 Hans Kapel painstakingly drew and recorded several hundred carvings. [Hans Kapel is the son of the late Danish pre-historian Holgel Kapel, author of the Atlas of the Stone-Age Cultures of Qatar. The Danish expedition had made a preliminary recording in 1956, fortunately so, since the jebel has since been extensively damaged by quarrying. Here, on a range of low limestone outcrops, Kapel recorded an astonishing 333 "game-boards", mostly consisting of two parallel rows of seven circular shallow holes or cups, although some had more than two rows or a larger number of holes. There were also "rosettes", usually composed of nine holes around one central hole. In addition to these were a total of 124 ship drawings in bas relief, showing long boats, pointed at each end and powered by oars, some with anchors of stone or metal. There were also 17 linear engravings of ships, some identifiable as Portuguese in style and therfore not earlier than the fifteenth century AD., or as battil and bagulah, the largest of the ocean-going Arab dhows. Besides the huge range of carvings at Jebel Al Jusasiyah there were several deep circular pits cut into the rock and at least two large, shallow circular or rectangular basins, apparently intended to hold water or some other liquid. Between 1981 and 1984 Prof D.F. Hawkins, a British consultant on the staff of Hamad Hospital, undertook a study of the rock-carvings at Al Furaihah on the north-west coast. This was published in the National Museum's journal Arrayan. The limestone outcrops at Al Furaihah extend 350 m from north to south and 100 m in the other direction, and are situated 1 km north of Zubara Fort. [There are also a large number of similar carvings on an extensive outcrop of limestone nearer the coast, which have not as yet been recorded.] The predominant feature at Al Furaihah is the presence of hundreds of double rows of cupmarks, single or double cupmarks, and rosettes. There are also large, shallow basins as at Jebel Al Jusasiyah, and several carvings of footprints in the shape of a human footprint complete with toes. There is only one comparable example at Al Jusasiyah. In 1956 the Danish archaeologist P.V.Glob, together with T.G. Bibby, had visited Al Furaihah, the first archaeologists ever to do so. They noted the presence of a number of mysterious symbols: and Glob, rather over-enthusiastically, declared that "....these designs must undoubtedly be viewed as evidence of an ancient fertility cult, which bas survived in this area up to modern times." He also interpreted the cup-marks in the same way. It now seems certain that these cryptic symbols are in fact wasm [pronounced "washm"]: camel-brand marks used by the Bedouin nomads. [Geoffrey Bibby's humorous comment on this, when he re-visited the site with us last year, was that Glob was sometimes a little too apt to interpret things in terms of fertility symbols!] Common to all the rock carving sites in this country are the double rows of "game-board" holes, single holes, double holes linked with a channel, and deep circular or oval pits and basins. The ship carvings of Jebel Al Jusasiyah are unique. Few instances of wasm occur except at Al Furaihah and the outlying jebel north of it and adjacent to the coast, so it was with some excitement that we noted the presence of a large and varied number of wasm at Jarr Umm Tuwaim.

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Fig 11.5.5: Rock carving sites in Qatar

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The Miocene Guide of Qatar, Middle East (Dam Formation) 1. Jarr Umm Tuwaim - the Wasm

The domestication of the camel in Arabia goes back at least 3000 years. W.Facey in The Story of the Eastern Province of Saudi Arabia describes how, towards the end of the second millenium B.C., instability in Mesopotamia disrupted Gulf trade to the extent that sea-going trade, which had been developed and expanded by the wealthy and sophisticated civilizations of Dilmun and Magan, gradually declined and was replaced by overland trading routes using the domesticated camel as a beast of burden. By the late second and early first millenia B.C., trading settlements had sprung up on overland routes from the Yemen. From these caravanserai developed the great trading cities of the Arabian interior. Camel carvings appear on an Umm-an-Nar type tomb in the U.A.E., suggesting the importance of this animal to the people of the time. Climatic changes assisted the tendency towards camel pastoralism. Towards the end of the third millenium, the climate became drier. Some of the people practicing agriculture in the oases and wadis would have been forced to find other means of subsistence, which meant increasing their mobility. Gradually, the highly-specialized life of camel herding evolved. The initial use of the camel as a milk animal probably supplemented the herding of sheep and goats, and only later may its potential as a beast of burden have been realized. Over a thousand years later comes the first recording of the camel in battle, in the 9th century B.C., when camel-riding tribesmen carried out raids on the settled farmers of the oases. A large grazing animal such as a camel needs to range over a very wide territory in order to find sufficient food, particularly in the hot, dry summer when fresh vegetation is hard to come by, and so it was necessary from the start to find a way of clearly marking the ownership of each animal, to avoid disputes with other families or clans.

Fig 11.5.6: Camel carved on a stone slab, Umm an-Nar, third millennium B.C http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) The practice of branding the camel on the neck or thigh with a red-hot iron appears to be of immense antiquity. The photograph reproduced below shows fragments of clay models of camels from the city of Thaj in eastern Arabia, dating to the second half of the first millenium B.C. A number of small camel figurines were found, made of red or buff clay with a cream slip, and these particular fragments are inscribed with what appear to be wasm. This identification appears to be borne out by Klaus Ferdinand in Bedouins of Qatar, who observed that camels were always branded on the left side of the neck or on the left thigh. Iron tent pegs were sometimes used to carry out the marking. Burning with red-hot iron rods was also used as treatment for a variety of ailments and injuries both in camels and humans.

Fig 11.5.7: Fragments of camel figurines from Thaj, eastern Arabia, first millenium B.C. The brand-marks were known by a variety of traditional names, for example:

a gate:

a camel's chin rope:

a tool used for twisting camel hair into rope:

a bird's foot:

a musical instrument:

a comb:

a key:

a catapult:

scissors:

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig 11.5.8: Camels branded on the left thigh Some 250 km to the south-west of Jarr Umm Tuwaim lies the oasis of Yabrin in Saudi Arabia. T.G. Bibby in A Preliminary Survey in East Arabia 1968 recorded that on the roof of a low cave on Jebel Makhruq in the oasis were many wasm carvings. One resembles P.V. Glob's "fertility symbol" at Al Furaihah, and two others Umm Tuwaim.

and

are similar to the wasm on Jarr

Fig 11.5.9: Cave with wasm carvings, Jebel Makhruq, Yabrin, eastern Arabia

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig 11.5.11: Spatial distribution of the main tribal groups at the turn of the [20th] century in Qatar

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The Miocene Guide of Qatar, Middle East (Dam Formation) Jarr Umm Tuwaim appears to lie within the area of Qatar frequented by the Al Murrah nomadic people, and used by them for grazing their camels, sheep and goats [see map]. Dr. Anie Montigny, who spent 1978-1982 in Qatar studying the Al Na'im, remarked in conversation with me that the Al Murrah were often considered to be the most 'pure' of the true Bedouin, a powerful, warlike people who for centuries had seasonally migrated between Qatar and Saudi Arabia, long before modern political boundaries had come into existence. J.G. Lorimer in the Gazetteer of the Persian Gulf 1908 somewhat censoriously remarks that "the Al Murrah appear to be the wildest, most dangerous and least civilized of the nomad tribes in their part of Arabia, and to exist, to an appreciable extent, by plunder. They are said to be staunch friends to those whom they recognize as neighbors; but otherwise they are treacherous and untrustworthy, and they sometimes betray persons who take sanctuary with them." He adds that the principal wealth of the Al Murrah was in camels. He also mentions that very often they had to exist entirely without water, using the milk of their camels both for drinking and cooking, for example for boiling rice. The earliest European travel account of Qatar, written by the former British Indian army officer W.G.Palgrave in 1862-3, describes the predicament of the coastal dwellers, who lived by fishing and pearling and suffered constant raids by the Al Murrah and the Al Manasir tribesmen. The south of Qatar was dominated by these two tribes, the centre by the war-like Beni Hajir, who successfully deterred any European from venturing into the interior until 1913. The north was peopled by the Al Na'im, but all these territorial boundaries were, of course, extremely fluid by modern standards. It would seem that the purpose of the wasm carvings on Jarr Umm Tuwaim was to leave a permanent record of the nomadic peoples using this area and claiming it as their own. Perhaps the wasm should be seen, not merely as camel-brands, but as a declaration of the ownership of grazing rights in a particular area. The same brand-mark was doubtless in use for many centuries. On page 346 of Klaus Ferdinand's Bedouins of Qatar is a photograph of a master well-builder carving a sheikh's wasm into the newly-plastered side of a well. The Rock may have marked a resting-place on a migration route. It may also have served as a focal point for periodic clan gatherings. The presence of so many graves clustered around Jarr Umm Tuwaim suggests either that the people camped here for long periods or that they made a point of bringing their dead to be interred here. We may confidently say, therefore, that this isolated landmark was formerly of considerable significance to the Bedouin who roamed over this area.

2. Jarr Umm Tuwaim - The "Game-Boards" In common with all other rock-carving sites in Qatar, Jarr Umm Tuwaim bears many double rows of holes, some of which are connected by a channel, and some single holes. There is also a single large deep oval hole, similar to those at Jebel Al Jusasiyah and Al Furaihah, and what may be an unfinished "rosette". These are scattered over the southern end of the rock and one 10 x 2 row of cup-marks, measuring 1.8 m in length is the largest carving of this type I have come across anywhere in Qatar. A unique feature of the Jarr Umm Tuwaim "game-boards" is the presence of a single central hole half-way along between the two rows, plus a single circular hole at the end. The 1.8 m double row has in addition two separate holes at one side and one on the other. The weathered condition of the carvings makes it unlikely that they were created in the recent past but, as with all the petroglyphs of Qatar with the exception of the ships at Jebel Al Jusasiyah, it is impossible as yet to assign a date to them with any confidence.

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig 11.5.11: Large game-board at the southern end of Jarr Umm Tuwaim (length 1.08 m)

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The Miocene Guide of Qatar, Middle East (Dam Formation) What was the purpose of the "game-board" carvings? Kapel, Hawkins and others considered that the parallel rows of cup-marks were used for playing the ancient game known to archaeologists as the "mancala game" because that happened to be the African name under which it was first recorded by Europeans. Here in Qatar the game certainly was played in former days, the double rows of cupmarks being known locally as Al Haloosah. In Bahrain and Oman it was called Al Judairah. The "rosette" game was known as Al Aailah, but I have no information as to how it was played. Michael Rice in The Archaeology of the Arabian Gulf refers to the double rows by another Arabic name, Al Huwais. It is found in almost every African country where it appears under countless names, and it may have been introduced into Africa by Arab traders. The slave-trade spread the game to Cuba. It is also known in India and Malaysia. During my years in West Africa I saw many versions of this game being played. I even learned to play it myself after a fashion, although my young daughters under the expert tutelage of our Tuareg night watchmen became far speedier and more skilful players! Each player has up to 35 counters which he drops into his own and his opponent's cups, working his way round and round the board. After dropping the last counter into one of his opponent's cups he may claim the contests if the cup contains one or three stones. The same applies if the cup to the right of the last one contains one or three counters. [In Africa, the large green seeds which grew in pods on a species of tree were used as counters, but I also saw pebbles and small shells in use.] Put like this the game sounds childishly simple, but in fact it is played at great speed and requires considerable skill. Bluffing one's opponent as to the number of counters held in the hand is important, as is the ability to calculate in advance the numbers in each cup. It is tempting to go along with Kapel and Hawkins and identify the cup-marks on Jarr Umm Tuwaim and the other rock-carving sites as variations of the mancala game, but a number of problems then occur. For a start the sheer number of boards. Why should anyone in his senses go to the trouble of carving out a new board each time he wanted to play? On Jarr Umm Tuwaim as at Jebel Al Jusasiyah, the double rows of holes sprawl at random across each other, often partly obliterating the rows beneath, in an apparently aimless proliferation of frenetic carving activity. Michael Rice amusingly sums up the conundrum in his consideration of the Jusasiyah carvings: "It seems improbable that this very remote spot... was ever the site of so extended and feverish a cult of huwais-playing as to make the salons of Las Vegas or Monte Carlo seem atrophied and empty either of activity or excitement. ' Then there is the apparently random number of holes, ranging at Jebel A1 Jusasiyah from as few as two rows of three holes to two rows of fourteen, and even three and four rows of holes. I know from my own observations in Africa that although the number of holes and counters varied widely from region to region, within each region it was invariably consistent. It seems inconceivable that, if these rows of cup marks are indeed game-boards, the players could have employed such an immense number of variations. Finally, there is the curious fact that at Jebel Al Jusasiyah and Al Furaihah some of the so-called game-boards are carved on the sloping surfaces of the rock, where the cups could not possibly have retained any counters. In addition, at Al Jusasiyah, some of the holes, particularly those in formations of three or four rows, are too small to have held any counters larger than a grain of rice. So, if the parallel rows of holes on Jarr Umm Tuwaim and the other petroglyphic sites are not games, what are they? Countless suggestions have been put forward, ranging from pearl-sorting [highly improbable], to primitive book-keeping, to astronomical calculators. At present it seems that, along with the Bronze Age cup and cup-and-ring marks of the northern England and Scotland, http://leblanc.jacques.googlepages.com/fossilhome

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The Miocene Guide of Qatar, Middle East (Dam Formation) despite extensive research we still have no real idea of their true purpose and their significance to the people who made them.

Fig 11.5.12: The reservoir system at Jarr Umm Tuwaim

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The Miocene Guide of Qatar, Middle East (Dam Formation) 3. Jarr Umm Tuwaim - The Reservoir On the morning of the 27 March, having traced and drawn some of the wasm, I went to the sloping northern end of the rock to examine a network of shallow channels, apparently worn by rain-water, which had appeared of natural origin to me when I had looked briefly at them the previous day. On closer examination it was clear that a tracery of faint, thin, man-made grooves extended from the natural channels towards a large patch of fine sand at the lower end of the rock. I suspected the presence of some kind of water-collection system and dug into the sand, almost immediately uncovering the mouth of a vertical shaft leading into the rock. During the next two hours, with the assistance of Mike Gardiner, three of these shafts were uncovered, together with the beginnings of an unfinished fourth. All led into a natural reservoir in the rock, formed from one of the cavities mentioned earlier as honey-combing the limestone. The central shaft was the deepest at 68 cm. The interconnecting horizontal passages linking the three shafts at the bottom had been deliberately blocked with rocks, for reasons not at present clear. Clearly, a heavy fall of rain on the wide, smooth surface of the rock could be skillfully diverted into this small underground reservoir, yielding a source of cool, clean drinking water, infinitely precious to the Bedouin struggling to eke out a living in this harsh uncompromising landscape. The shafts [two circular and one square] appeared to have been dug using metal tools, but there is no clue as to their date. Disappointingly, the fine sand which packed them contained not a single pot-sherd. The densely compacted sand, which took some effort to remove, especially when we reached the reservoir beneath the shafts, indicates that the system could not have been in use for many decades. The three shafts would undoubtedly have been covered with flat stones to prevent evaporation and keep the water free of blown sand, but these have now disappeared. I have not come across any similar water-collecting system anywhere else in Qatar. It is worth noting perhaps that at Ummahat Al Maghati in the Al Wakra area there are a number of holes in the rocky terrain, reaching a depth of a metre or more, which fill with water in the rainy season. They are covered with neatly-shaped stone lids to prevent evaporation. [The Arabic word maghati is the plural of the word meaning "covers".] Mike Gardiner suggests that the interior of the shafts and reservoir could perhaps have been coated with animal fat, to render the limestone less porous and retain the precious water supply longer. To sum up, we can say that the wasm carvings and rows of holes on Jarr Umm Tuwaim, plus the water reservoir, and the complete absence of any similar man-made markings for many kilometres around, indicates that this small but highly significant site occupied an important place in the consciousness of the nomadic peoples of the area. It seems surprising that it has not previously been studied or recorded. Frances Gillespie April 1998 Email (as of October 2009): [email protected]

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The Miocene Guide of Qatar, Middle East (Dam Formation) Acknowledgements My thanks go first and foremost to my husband David Gillespie, for his support and encouragement and for carrying out a survey and making drawings of the Rock. Dr. Bill George scanned my photos into his computer, thereby enabling me to produce for the first time a report with illustrations in colour! Researcher Osman A. Majeed of the Geographic Names Project at the Centre for Geographic Information Systems has made every effort to discover if " Jarr Umm Tuwaim" has an Arabic name [so far without success] and supplied the information on the water-holes at Ummahat Al Maghati. Saleh Ghareeb and Hamad Al-Muhannadi of the G.C.C. Folklore Centre, Doha, provided me with some information about wasm and translated the Arabic terminology. The binding of this report is by courtesy of Westbury and Northcrofts.

Bibliography T.G.Bibby: Preliminary Survey in East Arabia 1968 P.V. Glob: Prehistoric discoveries in Qatar. KUML 1957 pp 167-178 W.Facey: The Story of the Eastern Province of Saudi Arabia 1994. K. Ferdinand: Bedouins of Qatar 1993 H. Kapel: "Rock Carvings at Jebel Jusasiyah" Arrayan Vol. -No 8 1983. [The journal of the Qatar National Museum.] D.F.Hawkins: "Rock carvings at Al Furaihah" Arrayan Vol. No. 9 1984 J.G. Lorimer: Gazetteer of the Persian Gulf 1908 C. Gillespie: "Rock Carvings of Jebel Jusasiyah" Gulf Times 4 April and 11 April 1996

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The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 1006

Description Beachrock with clasts

Position (Lat/Lon, WGS 84) N24.87206 E50.87763

Altitude (Metres) 0

1011

Limestone below green shale displaying lots of burrows (Two pictures - one with view to the green shale cliff)

N24.87464 E50.87174

-3

1012

This is a very large area of red and brown limestone

N24.88634 E50.87310

1

1013

This is a very large area of mainly red limestone (proof that the area was exposed to air when it was formed)

N24.88668 E50.87649

1

N24.88536 E50.87334

1

N24.88465 E50.87410

-1

N24.88271 E50.87659

2

N24.87383 E50.87533

0

N24.88169 E50.87933 N24.88131 E50.87879

7 6

N24.88189 E50.87721

5

N24.88217 E50.87480

4

N24.88233 E50.87378

4

N24.88012 E50.87350

4

N24.87992 E50.87330

3

N24.87663 E50.87448

4

N24.87588 E50.87461 N24.87585 E50.87465

4 4

N24.87668 E50.87886

6

N24.90077 E50.92689

45

N24.90108 E50.92688

45

1014

1015 1016 1020 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032

1033

1034

1035

Intertidal/Beach area. The two pictures shows the obvious "surf zone" which can also easily be seen on any satellite image One dugong rib in intertidal/beachrock. Also, about 25 metres northeast of this location start appearing some shells in the rock Beachrock with clasts and large shells Sirenian/Dugong rib which has started deteriorating due to the effect of the salt coming from the sabhka (1 picture) Large bivlaves encrusted in rock Large bivlaves encrusted in rock Conglomerate. The whole area here dsplays large dolines created by the dissolution of the rock in the subsurface One sirenian/dugong rib in yellowish limestone Red & yellow sediments in deformed cross-beds. The surface also shows ripples. This occurs in an intertidal/beach environment Two sirenian/dugong ribs in yellowish limestone Several sirenian/dugong ribs (at least 7) and two vertebrae on a mound of a yellowish limestone The yellow limestone cracks under your feet due to the salt reacting with the calcium in it One thick sirenian/dugong rib and one vertebra One large sirenian/dugong vertebra One sirenian/dugong rib with large bivalves, in grey limestone sometime cracked/fractured by the action of the sun and water. Looking at this limestone from a distance (walking from west to east), it has an icy appearance Large and small gastropods and bivalves in coquina style limestone (2 pictures) From top to bottom (one picture of whole section): Large and small gastropods and bivalves in coquina style limestone / White Limestone / Clast at bottom of white limestone (one picture)

1036

From top to bottom: - Large and small gastropods and bivalves in coquina style limestone / - White Limestone

N24.88976 E50.93048

41

1037

Large burrow (one picture) in limestone

N24.89307 E50.92953

39

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150

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 1038 1039 1040 1041 1042 1044 1046 1047 1054 1055 1065

1066 1067 1068 1071 1072 1073 1074 1075 1076 1077 1078 2001 2002 2003

2004

2005 2006 2007

Description Outcrop of the layer displaying large gastropods. (Side of a large doline) Outcrop of the layer displaying large gastropods (Side of a large doline) Outcrop of the layer displaying large gastropods (Side of a large doline) Top of Lower Salwa. Weathered coquina (Side of a large doline) Lower Salwa Limestone. (Side of a large elongated doline) Lower Salwa Limestone Greenish shale on slope. Some gastropods on upper limestone Top of the Lower Salwa Limestone Yellowish limestone stratigraphically below the green shale Coquina / packstone with intertidal/beach features. Current was most probably from North to South. (Below this packstone is the yellow limestone) Coquina / packstone with intertidal/beach features. Current was most probably from North to South. (Below this packstone is the yellow limestone) Yellow Limestone displaying small clasts / conglomerates at the base Yellow Limestone displaying large clasts / conglomerates (see picture) Gastropod layer White limestone Top Lower Salwa Gastropod layer Gastropod layer Gastropod layer with corals (one picture) Gastropod layer with corals (one picture) Weathered echinoderms in white limestone Echinoderms in white limestone. At the base can be seen a layer of burrows. Echinoderms: Fibularia Damensis. They occur on the west side of a small hill Echinoderms: Fibularia Damensis On the picture, they occur 2 metres from the side of the car. On the picture can also be seen the red shale of the Upper Salwa By the time this report comes out, the site may have been destroyed by the road construction currently (Sept 2008) going on Man-made channel displaying silty white limestone A layer of burrows in white limestone 28.0m = weathered coquina level (up to the next point to the west)

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.91832 E50.92822

48

N24.91881 E50.92868

46

N24.91919 E50.92872

45

N24.91798 E50.92753

46

N24.93765 E50.92121

47

N24.94698 E50.91797 N24.87814 E50.93669

32

N24.87867 E50.93566 N24.87914 E50.88134

39 9

N24.88405 E50.88177

10

N24.88451 E50.87950

-1

N24.88390 E50.88052

1

N24.88318 E50.88047

-6

N24.88364 E50.88057

-3

N24.89466 E50.96140 N24.88734 E50.95275 N24.88171 E50.94561 N24.88016 E50.94359 N24.87877 E50.94097 N24.87800 E50.94130 N24.87951 E50.94111 N24.87448 E50.94372 N24.86506 E50.91461

71 49 39 36 36 34 33 31 24

N24.86662 E50.91311

26

N24.86242 E50.90692

4

N24.86217 E50.90580

6

N24.91179 E50.86884 N24.86529 E50.91399

21 22

N24.90948 E50.88833

25

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151

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.90905 E50.88618

23

N24.90894 E50.88506

23

N24.90159 E50.87627

12

N24.90436 E50.87943

16

N24.90399 E50.87961

15

N24.90200 E50.88101

16

N24.90133 E50.88099

18

N24.90048 E50.88012

16

N24.92129 E50.87189 N24.92187 E50.86953 N24.92217 E50.87219 N24.92253 E50.87256 N24.92156 E50.87090 N24.92508 E50.86658 N24.89292 E50.88004

22 20 23 23 21

N24.93413 E50.85336

8

N24.90206 E50.87589 N24.90667 E50.88152

14 20

2034 2035 2036 2037

28.5m = start of another weathered coquina level up to the next point to the west Weathered coquina level Thousands and thousands of echinoderms (Fibularia Damensis) over a large area where a white limestone outcrops Limestone covered with echinoderms (Fibularia Damensis) Limestone covered with echinoderms (Fibularia Damensis). Note the circular structure in which they occur Limestone covered with echinoderms (Fibularia Damensis). Note the two circular structures in which they occur Limestone covered with echinoderms (Fibularia Damensis). Large shells are also present. Note the two circular structures in which they occur. The scale in the picture is 1m. Limestone covered with echinoderms (Fibularia Damensis). Coquina with some large bivalves Coquina with some large bivalves Echinoderms on eroded edge Echinoderms on eroded edge Echinoderms on eroded edge Coquina White limestone with interesting coral shapes Overturned (almost vertical) rocks. Shells and corals with some echinoderms about 20m SW from picture location Echinoderms (Fibularia Damensis) 29.0m = Packstone Weathered/Polished limestone (stratigraphically below coquina level) Coquina Very top of the Middle Salwa. Loose large shells/bivalves from the base of the Upper Salwa Large shells/bivalves in the rock Limestone covered with echinoderms (Fibularia Damensis). Limestone covered with echinoderms (Fibularia Damensis). Copuina of the Middle Salwa. Immediately to the east, starts the Upper Salwa Echinoderms in white limestone Echinoderms in white limestone Echinoderms in white limestone Echinoderms in white limestone

N24.86588 E50.90430 N24.86547 E50.90440 N24.86584 E50.90486 N24.86601 E50.90470

12 11 13 14

2038

Echinoderms well encrusted in white/brownish limestone N24.87473 E50.91325

26

2008 2009 2010 2011 2012

2013

2014

2015 2016 2017 2018 2019 2020 2021 2022 2023 2025 2026 2027 2028 2029 2030 2031 2032 2033

N24.90393 E50.88459 N24.90405 E50.88688 N24.89931 E50.88414

24

N24.90091 E50.88122

19

N24.90369 E50.88026

20

N24.90409 E50.88013

20

N24.88322 E50.88665

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152

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 2039 2040 2041 2042

Description

Position (Lat/Lon, WGS 84) N24.89319 E50.92582 N24.90060 E50.92457 N24.88447 E50.92168 N24.88291 E50.92520

Altitude (Metres) 41 52 31 34

N24.87387 E50.91338

30

N24.92369 E50.91978

50

2049 2050 2051 2052 2053 2054 2056 2057 2059 2060 2061 2062 2063

White limestone. Top of Middle Salwa Weathered limestone/coquina. Top of Middle Salwa Coquina (Top Middle Salwa) Coquina (Top Middle Salwa) Echinoderms with few bivalves occuring in a circular feature Coquina of the top Middle Salwa Circular feature in the Middle Salwa probably due to dissolution of the underlying Eocene rocks (karst) Limestone of the Middle Salwa Top limestone Loose shells/Bivalves (Ostrea & Pecten) from the bottom of the Middle Salwa Middle Salwa Limestone Echinoderms (Fibularia Damensis) Echinoderms (Fibularia Damensis) Echinoderms (Fibularia Damensis) Echinoderms (Fibularia Damensis) White Limestone Top of the Midle Salwa Weathered coquina Middle Salwa ridge Top of the Middle Salwa White limestone White limestone with very few echinoderms Top coquina of the Middle Salwa Top coquina of the Middle Salwa

2064

White limestone with lots of small bivalves (one picture)

N24.86799 E50.89507

11

2065

White limestone

N24.86958 E50.88880

7

2066

Limestone of the Middle Salwa covered with Hofuf gravel N24.86345 E50.88596

13

2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2079

Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Basal white limestone of the Middle Salwa Weathered coquina / packstone Weathered coquina / packstone (good candidate to look for dugong bones!!) White Limestone hill White Limestone White Limestone White Limestone White Limestone

N24.88766 E50.88228 N24.88873 E50.88137 N24.89013 E50.88066 N24.89132 E50.87958 N24.89194 E50.87933 N24.89155 E50.88052 N24.89380 E50.87904 N24.89443 E50.87808 N24.89590 E50.87674 N24.89636 E50.87363 N24.89723 E50.87417 N24.87334 E50.89209

14 16 15 14 13 14 15 13 14 10 10 9

N24.87522 E50.88920

8

N24.89708 E50.87109 N24.90078 E50.86812 N24.90897 E50.86519 N24.91044 E50.86466 N24.91226 E50.86443

4 4 8 8 8

2043 2044 2045 2046 2047 2048

2080 2081 2082 2083 2084 2085

N24.92378 E50.91683 N24.91886 E50.92768 N24.93500 E50.91706

59

N24.93789 E50.92110

47

N24.94898 E50.91828 N24.86597 E50.90679 N24.86598 E50.90633 N24.86584 E50.90626 N24.86587 E50.90652 N24.85866 E50.92306 N24.86399 E50.92995 N24.86318 E50.93131 N24.87545 E50.92537 N24.86214 E50.91191 N24.86103 E50.90759 N24.86895 E50.89407 N24.86642 E50.89615

-29 14 12 14 20 25 23 33 15 9 11 13

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153

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109

Position (Lat/Lon, WGS 84) N24.91508 E50.86065 N24.92739 E50.85983 N24.88459 E50.90940 N24.92446 E50.85920 N24.94458 E50.94328 N24.94190 E50.94404 N24.94188 E50.94315 N24.94270 E50.94297 N24.94272 E50.93843 N24.94342 E50.93612

Altitude (Metres) 7 12 39 12 69 71 67 66 64 56

N24.85709 E50.90083

6

N24.85683 E50.89979

6

N24.90140 E50.96727 N24.90114 E50.96629 N24.90104 E50.96182 N24.89927 E50.96195 N24.89800 E50.96484 N24.89895 E50.96677 N24.89756 E50.96762 N24.89716 E50.96980 N24.89608 E50.97038 N24.89452 E50.96229 N24.88019 E50.94329

74 72 72 74 72 78 74 79 79 77 37

N24.87928 E50.94134

35

N24.87927 E50.94185 N24.87515 E50.94538

35 32

N24.86411 E50.90153

10

N24.86431 E50.90130 N24.86435 E50.90068

8 11

N24.86401 E50.90066

9

N24.86439 E50.90124 N24.86395 E50.90071

7 10

My first shark tooth from the Miocene Dam Formation. It comes from the top of the Middle Salwa white limestone (see pictures). Just above is the green shale at the base of the Upper Salwa. This shale is much thinner here N24.87348 E50.91975 than anywhere else in Area 1. The white limestone also contains some large bivalves. One sirenian/dugong proximal rib was also found about 4 metres to the south

26

Description White Limestone Packstone White limestone White Limestone (one picture) Top of Middle Salwa (Packstone/weathered coquina) Top Middle Salwa - Packstone Top Middle Salwa - Packstone Top Middle Salwa - Packstone Top Middle Salwa - Packstone Top Middle Salwa - Packstone Packstone. Good prospect to find sirenian/dugong bones. Packstone. Good prospect to find sirenian/dugong bones. Disturbed beds. No obvious fossils Small bones were found here (one picture) Top Middle Salwa. No obvious fossils Top Middle Salwa. No obvious fossils packstone

Middle Salwa. Very disturbed (one picture) Top Middle Salwa Small sirenian/dugong bones were found here (two pictures)

2110 2111 2112 2113 2114

2115

2116 2117

2118

Sirenian/dugong ribs. Two ribs occur here within 3 metres of each others. Please do not destroy. Leave them as they are for others to enjoy. The ribs are in a packstone Small broken sirenian bone still in rock (packstone) Small sirenian bone protruding from rock (packstone) 1) One long (50cm) almost complete sirenian rib (one picture) 2) 1.5m south are imprints of other ribs (eroded away) and thoracic vertebrae with long spinous process and large vertebral foramina (Two pictures) They occur in a packstone Small broken sirenian bone still in rock (packstone) Sirenian/dugong vertebrae

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154

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.87344 E50.91978

26

2120 2121 2122 2123 2124 2125 2126

Proximal rib of some heavy weight sea cow/sirenian/dugong (see picture) in the white limestone at the top of the Middle Salwa. Large bivalves also occurs in the limestone, and a shark tooth was also found about 4 metres to the north Limestone at the top of the Middle Salwa Limestone at the top of the Middle Salwa Limestone at the top of the Middle Salwa Limestone at the top of the Middle Salwa Limestone at the top of the Middle Salwa Middle Salwa Middle Salwa

N24.86298 E50.91598 N24.86739 E50.92649 N24.86600 E50.92759 N24.86534 E50.93085 N24.85961 E50.93275 N24.90026 E50.95664 N24.90470 E50.95837

17 29 26 28 22 65 68

2127

Wide area displaying large corals/burrows. (1 picture)

N24.94747 E50.85268

15

2128 2129 2130 2131

N24.86023 E50.89445 N24.86227 E50.89145 N24.86321 E50.88884 N24.86620 E50.88158

8 8 7 9

N24.87475 E50.87235

2

N24.87693 E50.88095 N24.88083 E50.88270 N24.88489 E50.88179 N24.88748 E50.87963 N24.88774 E50.88129 N24.88741 E50.88174 N24.88796 E50.87072 N24.89613 E50.87284 N24.89833 E50.87038 N24.92018 E50.85785 N24.92222 E50.85603

13 9 10 12 14 15 11 13 4 6 3

N24.94317 E50.85127

11

N24.94522 E50.84914

10

3001 3002

Limestone with lots of burrows Limestone with lots of burrows Green shale capped by a laminated sandstone Green shale capped by a laminated sandstone Green shale. Horizontal bedding. Laminated layers of siltstone and shale which reflect intermittent settling of particles from suspension. Green shale capped by a laminated sandstone Green shale capped by a laminated sandstone Green shale capped with laminated sandstone Green shale Green shale Laminated siltstone over a flat area Green shale capped with laminated sandstone Weathered coquina / packstone Weathered coquina / packstone Limestone with lots of shells Limestone with lots of shells Green clay at bottom of a cliff capped with silty white limestone (1 picture) Hill: Green clay at bottom of a cliff capped with silty white limestone White limestone Ridge of top Lower Salwa (no gastropods). Greenish shale on slope Green clay in 2m cliff Burrows

3003

2119

2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146

N24.94777 E50.92622 N24.86138 E50.93363

21

N24.90929 E50.87638 N24.86856 E50.90222

26 19

Silty limestone with some shells, then white limestone.

N24.91406 E50.87868

28

3004

From this point to the next westerly point, we lost about 3m due to sand cover 21.5m = white limestone 23.5m = green clay & weathered limestone 25.0m = Small bivalves & gastropod limestone (many of them)

N24.90942 E50.89130

36

3005

This is the location where Dr. Dill found a Shark tooth. No other teeth were found.

N24.88317 E50.90894

67

2147

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155

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS #

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.88222 E50.88850

22

N24.91445 E50.88272

24

N24.91484 E50.88311

27

N24.86754 E50.90512

22

N24.91504 E50.88468

29

N24.91517 E50.88512

27

3012

Scallop shells Stratigraphical column shows the Upper Salwa from top to bottom as: Coquina White limestone Red clay (especially on the north side of the hill) Green clay Scallop shells (in fairly large quantity)

N24.93557 E50.88062

30

3013

Area of red clay shown in Zeuges

N24.91609 E50.88498

30

3014

Vertical burrows are found here. Check also the rocks that have fallen down the small cliff (as seen in picture)

N24.86406 E50.89777

8

3015 3016 3017 3018

Limestone with several small bivalves & gastropods Green to brown shale Coquina with Herringbone cross-bedding Coquina Layer

N24.91564 E50.88641 N24.86719 E50.90682 N24.86578 E50.89667 N24.86103 E50.90517

31 19 23 15

3019

Coquina Stratigraphical column shows the Upper Salwa from top to bottom as: Coquina White limestone Red N24.93634 E50.88026 clay (especially on the north side of the hill) Green clay Scallop shells (in fairly large quantity)

42

3006

3007 3008 3009 3010 3011

3020 3021 3022 3023 3024 3025

3026

Description Burrows (with brown shale above) at the tip of a ridge. One picture of the ridge was taken from the Hofuf formation above Area of green clay - silty limestone with some shells white limestone - Sandy valley - Laminated & planar cross-bedded siltstone - green clay - red clay Area of Laminated & planar cross-bedded siltstone, reddish and sometime even pebbly and with burrows Burrows (with brown shale above) Area of Laminated & planar cross-bedded siltstone with burrows and interesting stratification at the surface / green clay / red clay Area of red clay

Weathered coquina Red clay layer Brownish to greenish shale. Burrows occur just few metres to the west Red clay cliff on the side of the road 20.5m = weathered coquina with wave/ripple structure at surface (flat field area). One picture A 3m thick white limestone cliff capped with weathered coquina

N24.93633 E50.88321 N24.86164 E50.90549

43 15

N24.87381 E50.89480

30

N24.86891 E50.91042

25

N24.90948 E50.89234

40

N24.91521 E50.88959

37

Very base of Upper Salwa. While the limestone containing the large bivalves at the base of the Upper Salwa can not be seen, the loose bivalves are present in N24.92317 E50.87445 the Hofuf sediments at the base of the slope with the "green clay" normally just above the said limestone

26

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156

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

3027

Coquina at the top of the Upper Salwa. The area is a cliff which displays the complete Upper Salwa Section. The coquina displays some cross-beds, and large N24.89161 E50.88407 burrows in a green clay can be seen on the western face of the cliff

34

3028

1) Loose large bivalves (base of Upper Salwa) - (1 picture, 3028a) 2) From this location, can be observed a cliff showing two-third of the Upper Salwa (1 panoramic N24.90590 E50.88813 montage/picture, 3028b) while a little higher can be seen the white limestone and a planar cross-bedded coquina capping the member (1 picture, 3030)

26

3029 3030 3031 3032 3033 3034

3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047

Limestone with small gastropods and shells Coquina capping the Upper Salwa. Picture shows the coquina, the red clay in a hill, the white limestone and a view to the valley Coquina capping the Upper Salwa Large surface ripples in coquina Large vertical and branch burrows

N24.90578 E50.88916 N24.90532 E50.89014

41

N24.90147 E50.89075 N24.89793 E50.88919 N24.85698 E50.88941

42 5

Very base of Upper Salwa. Some bivalves. Several 1cm N24.87625 E50.91437 (diameter) wide ironized balls loose at the surface Very brittle ribs laying at the base of the green shale (very base of Upper Salwa). Laying also in the centre of a vehicle track. Rippled weathered coquina. Very top of Upper Salwa Limestone of the Upper Salwa Red shale Green Shale Loose large bivalves from the very bottom of the Upper Salwa From top to bottom: White limestone Red shale Green shale From top to bottom: Limestone with small bivalves White limestone Red shale Green shale From top to bottom: Limestone with small bivalves White limestone Red shale Green shale Top of Upper Salwa (coquina) Top of Upper Salwa (coquina) Bulldozed Red & green shale (remains of a hill destroyed for the road construction). More of that hill can be seen just south of the highway Thin limestone layer Green shale Limestone of the Upper Salwa

27

N24.87527 E50.91252

25

N24.89535 E50.89154 N24.88037 E50.91829 N24.89511 E50.92361

33 27 45

N24.90322 E50.92114

50

N24.90414 E50.92053

57

N24.88804 E50.92229

35

N24.88589 E50.92427

37

N24.88856 E50.92278 N24.88878 E50.92148

46 37

N24.88208 E50.92471

32

N24.88199 E50.92273 N24.87877 E50.91822

29 34

3048

Hill covered with Hofuf gravels Green shale at the base of the Upper Salwa White limestone of the Middle Salwa The whole area surrounding the hill is Middle salwa

N24.88686 E50.92789

46

3049

Large hill: White Limestone Green shale

N24.88838 E50.92639

44

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157

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070

3071

3072 3073

Description Two small hills: Green clay at the base of Upper Salwa White Limestone of the Middle Salwa The whole area surroundings the hills is Middle Salwa Red & Green Shale Red & Green Shale Red & Green Shale White Limestone White Limestone Upper Salwa covered with Hofuf gravels Top Upper Salwa Weathered coquina with large ripple marks Top Upper Salwa Lots of large shells/bivalves of the lowest layer of the Upper Salwa Weathered coquina of the Upper Salwa Green shale Red clay on flat area, surrounded by white limestone small cliff of the Upper Salwa Red flat on flat area White Limestone Red shale (1 picture) Coquina. White limestone. (sirenian/dugong broken bones/ribs and one vertebra were found here...see the two pictures) Red and green shale Green shale capped with brownish limestone and Hofuf gravels Green shale capped with brownish limestone and Hofuf gravels Green shale capped with white & brownish limestone Weathered coquina (Top Upper Salwa)

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.89299 E50.92621

45

N24.90962 E50.91941 N24.91996 E50.91686 N24.92164 E50.91623 N24.90473 E50.91753 N24.90385 E50.91589 N24.92248 E50.91684

53 52 48 49 50 53

N24.89439 E50.91784

-49

N24.91606 E50.91003 N24.92125 E50.91678

52

N24.92485 E50.91023 N24.86626 E50.89662

58 8

N24.86757 E50.93512

23

N24.87045 E50.94074 N24.86974 E50.93575

23 22

N24.87186 E50.94242

26

N24.87270 E50.94201

27

N24.87894 E50.92603

37

N24.87581 E50.92564

34

N24.87132 E50.92117 N24.87315 E50.92021

26 28

White Limestone with 3D burrows. Green shale (0.8m thick) occurs just below; this green limestone pinches out N24.86941 E50.92200 more to the north. Another white limestone just below the green shale represents the top of the Middle Salwa

26

- Top of hill is coquina. - White limestone with burrows; N24.86775 E50.92282 Green shale Weathered coquina with Hofuf gravel N24.86830 E50.93390

23 28

3074

Green shale (with burrows towards the top) interbedded with limestone and laminated sandstones

N24.86517 E50.90185

17

3075

Green shale (with burrows towards the top) interbedded with limestone and laminated sandstones

N24.86635 E50.90051

19

N24.86667 E50.90079 N24.86593 E50.89595 N24.86915 E50.89176 N24.86626 E50.89167

32 14 7 4

N24.86936 E50.89229

15

3076 3077 3078 3079 3080

Weathered coquina (Top of Upper salwa) Green shale Green shale Green shale (topped by a laminated sandstone) Green shale (topped by a laminated sandstone). Fractures in shale are infilled with gypsum crystals

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158

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 3081 3082 3083 3084 3085 3086 3087 3088 3089 3093 3094 3095 3096

3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114

Description

Position (Lat/Lon, WGS 84)

Top Upper Salwa coquina with cross beddings (wave N24.86484 E50.89586 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86392 E50.89486 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86369 E50.89302 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86384 E50.89313 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86543 E50.89232 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86698 E50.89041 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86750 E50.88976 ripples) Top Upper Salwa coquina with cross beddings (wave N24.86774 E50.88891 ripples) White and red limestone of the Upper Salwa N24.86343 E50.89313 Green and red shale N24.91895 E50.87660 Green shale N24.91470 E50.87378 Silty limestone with some shells / white limestone / N24.91516 E50.87723 Green shale Brown limestone Red clay Green clay Fragments of large bivalves (on both sides of hill) Two dead camels N24.94430 E50.94321 are also on top of the hill Brown limestone Red clay Green clay Fragments of large bivalves (on both sides of hill) A post looking like a N24.94170 E50.94371 "Street post" is on top of the hill Packstone with wave ripples (Top Upper Salwa) N24.94681 E50.88029 White Limestone N24.94709 E50.87670 Green shale N24.94603 E50.87227 Green shale with crystals of gypsum in fractures and N24.94373 E50.86966 loose soil Green shale with crystals of gypsum in fractures and N24.94156 E50.86942 loose soil Green shale and bivalves at the base N24.93918 E50.87437 Top packstone of the Upper Salwa N24.85815 E50.90210 Bottom green clay N24.85782 E50.90215 Packstone/coquina at the top of the Upper Salwa N24.85762 E50.90395 Base of Upper Salwa with loose large bivalves N24.89904 E50.96699 Upper Salwa covered with Hofuf gravels N24.89919 E50.96738 Loose large bivalves (green clay in cliff to the west) N24.89654 E50.96502 Top of Upper Salwa. Molds of small bivalves in N24.89639 E50.96483 packstone (one picture) Limit of the Upper Salwa. Loose large bivalves N24.90028 E50.96130 Top Upper Salwa N24.90050 E50.96033 - Top of hill is coquina. - White limestone with burrows; N24.86689 E50.92251 Green shale - Top of hill is coquina. - White limestone with burrows; N24.86546 E50.92081 Green shale http://leblanc.jacques.googlepages.com/fossilhome

Altitude (Metres) 20 13 6 6 6 8 8 9 7 28 22 28 73

75 43 31 23 20 20 24 10 5 11 80 80 74 82 74 81 21 21

159

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 3115 3116 3117 3118 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013

4014

4015 4016 4017

4018

4019 4020 4021 4022 4023 4024

Description

Position (Lat/Lon, WGS 84)

- Top of hill is coquina. - White limestone with burrows; N24.86697 E50.91652 Green shale Flat surface of limestone with burrows N24.86447 E50.91931 Flat surface of limestone with burrows N24.86382 E50.91606 White Limestone N24.86182 E50.92544 Columnar Stromatolites on a ridge (Metre 52 in Dill's N24.87121 E50.90547 section) Columnar Stromatolites N24.87723 E50.89599 Columnar Stromatolites N24.87122 E50.90283 Columnar Stromatolites N24.88683 E50.91055 Columnar Stromatolites N24.88694 E50.91073 Columnar Stromatolites N24.88140 E50.90805 Columnar Stromatolites N24.88315 E50.91150 Stromatolites with ?blisters? N24.85801 E50.90512 Crab/shrimp remains. N24.88547 E50.90665 Crab/shrimp Remains N24.88514 E50.90633 Gastropods & Bivalves N24.88462 E50.90623 Columnar Stromatolites below a Hummocky Deposit (1 N24.87578 E50.90845 picture). See chapter on Hummocky deposits Tepee structures and LLH stromatolites and centimeterthick laminae in clayey marlstones of the Lower Al N24.87048 E50.90373 Nakhsh Member Blister stromatolite. The picture shows Jeremy Jameson (ExxonMobil) looking at it. While looking at the blister, Dr. Jameson found what could be a broken part of a N24.85910 E50.90400 shark tooth laying on top of it. Identification could not be ascertain. 19.0m = Columnar stromatolites = oolitic grainstone 19.5m = Red limestone 20.0m = white N24.90982 E50.89536 limestone Limestone with burrows. One echinoderm was found N24.87541 E50.90881 here Burrows/Coral limestone N24.88527 E50.90647 Sirenian bones: It looks like a sternal element, and could be a xephisternum (the wider edge is the proximal end towards the skull, the broken side is distal or toward the tail, and the side with slight keel is ventral); This is too flat for a Protosiren, and may fit with Eotheroides or N24.86476 E50.89683 Eosiren sternal morphology (Identified by Dr. Iyad Zalmout in an email dated June 23rd 2008.). Other bones were also found between points 4018 and 4019. (See picture) Southern limit of where sirenian bones were found (4018 N24.86360 E50.89752 is the northern extension). See pictures Possible Sirenian/dugong bone? N24.86462 E50.89674 Hardground which starts the Lower Al-Nakhsh cycle N24.87003 E50.90380 Hummocky deposit (See chapter on Hummocky N24.87573 E50.90842 deposits) Stromatolites N24.85681 E50.89039 Very base of Lower Al-Nakhsh Red clay N24.89433 E50.89088 http://leblanc.jacques.googlepages.com/fossilhome

Altitude (Metres) 21 21 18 26 51 52 51 44 42 118 33 6 55 54 55 56 52

15

45 50 54

27

24 25 48 56 9 34 160

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 4025

Description White limestone covered with Hofuf gravel

Position (Lat/Lon, WGS 84) N24.89494 E50.89073

Altitude (Metres) 36

4026

Hill covered with the Hofuf gravels Lower Al-Nakhsh just N24.88819 E50.92309 below (25% of the section) Upper Salwa (75% of section)

54

4027 4028 4029 4030

Columnar stromatolites White limestone of the Lower Al-Nakhsh Peloid grainstone Metre 54 in Dill's section

N24.88721 E50.91528 N24.92026 E50.90276 N24.86523 E50.89705 N24.86432 E50.89669

39 62 17 26

4031

From top to bottom: - White Limestone - Red limestone A very small cave can be seen in the red limestone

N24.86684 E50.90092

32

4032

From top to bottom: - White Limestone - Red limestone

N24.86357 E50.89425

8

4033

From top to bottom: - White Limestone - Red limestone

N24.86455 E50.89312

7

4034

From top to bottom: - White Limestone - Red limestone

N24.86484 E50.89306

8

4035 4036 4037

Oolitic beachrock with shell fragments and clasts (Top of N24.89919 E50.89629 Lower Al-Nakhsh) Beachrock N24.90009 E50.89592 Beachrock (1 picture) N24.90042 E50.89593

62 64 63

4038

One vertebra and one small bone of a sirenian/dugong was found here. They were removed by the author since they were falling apart due to extreme erosion. The location also provided the author's first fossilized shark remain from the Miocene. As per an email received on December 28th 2008 from Dr. Iyad S. Zalmout at the Museum of Paleontology of the University of Michigan "what you are holding [figures b & c] is a unique specimen of a batoidae lower jaw (Pavement Teeth in Articulation). I think it is myliobatid Jaw. The lithofacies N24.85878 E50.90242 you are looking in is very promising to find more fossils." In short, it is the fossilized lower jaw of a Miocene stingray. And from Dr. Friedrich Pfeil in an email dated January 1st 2009: that´s an almost complete toothplate of a Myliobatis sp. - a very nice one! With 135 named species of which 78 could be valid names, it is impossible to give a correct species name, not at the moment. However, this is an important specimen for later determination. Keep it safe! All of the above were found in a pure white limestone (4 pictures)

11

4039

Sirenian/dugong bones (3 pictures + one with description). The one in picture "C" is described as such by Dr. Zalmout: "in picture Area-01_4039c you are looking at is the palatal view of right posterior corner of a N24.85941 E50.90188 sea cow skull, exactly at the squamosal, part of the pterygoid and part of the palatine." They have been removed by the author. A small myliobatidae jaw plate was also found here

-23

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161

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 4040 4041

Description Circular / oncoidal / blister stromatolites Stromatolites in white limestone. Pictures taken during the ExxonMobil Carbonate workshop of November 2008

Position (Lat/Lon, WGS 84) N24.85818 E50.90384

Altitude (Metres) 5

N24.87042 E50.90541

48

N24.90055 E50.95936

89

N24.90084 E50.96064

83

N24.90043 E50.96073

85

N24.89618 E50.96429

84

5002 5003 5005 5006 5007 5008 5009 5010

Red limestone of the Lower Al-Nakhsh topped with Hofuf gravels Red limestone of the Lower Al-Nakhsh topped with Hofuf gravels Red limestone of the Lower Al-Nakhsh topped with Hofuf gravels Red limestone of the Lower Al-Nakhsh topped with Hofuf gravels Gypsum crystals Gypsum crystals Oncoidal Stromatolites Stromatolite mounds Red Stromatolites Coquina Oncoidal Stromatolites Gypsum field

N24.86389 E50.89673 N24.87488 E50.90666 N24.88151 E50.90505 N24.89036 E50.89927 N24.89557 E50.90004 N24.89541 E50.89999 N24.85947 E50.90279 N24.93087 E50.89148

29 65 63 71 78 75 31 56

5011

14.5m = Gypsum crystal field

N24.90971 E50.89748

54

N24.90929 E50.89609

50

N24.90992 E50.89801

61

N24.90983 E50.89774

57

N24.90967 E50.89625 N24.91779 E50.90010 N24.85912 E50.90307

50 66 28

N24.88634 E50.89061

69

N24.89013 E50.89322 N24.87105 E50.90489 N24.89836 E50.89705

61 62 68

N24.89993 E50.89614

66

N24.89998 E50.89595

64

N24.90089 E50.89582 N24.90123 E50.89587 N24.90212 E50.89703 N24.90197 E50.89822 N24.90126 E50.89845 N24.90008 E50.89747 N24.89881 E50.90526 N24.89879 E50.90553

61 68 76 78 74 78 76 74

4042 4043 4044 4045

5012 5013 5014 5015 5016 5017 5019 5020 5026 5027 5028 5029 5030 5031 5033 5034 5035 5036 5037 5038

= White limestone

17.0m = Gypsum field = Beach rock & coquina = 2m of white limestone 10.5m = Stromatolite mounds (2 pictures) = Reddish bivalve & gastropod coquina rich in crystals of gypsum celestite/selenite 13.0m = Possible stromatolite mounds in limestone = white limestone 16m = Gypsum field with Hofuf pebbles Gypsum crystals Grainstone with oolite and Beach Rock Large Gypsum crystals (one picture). The scale is 1m. A similar picture can be seen in Dr. Dill's website at: http://www.hgeodill.de/AlNakhsh1.jpg Gypsum crystals Ooids. Metre 64 in Dill's section Large gypsum crystals Stromatolitic layer in cliff with apparent unconformity on top (2 pictures) Loose Oncoidal stromatolites and polished gypsum crystals (one picture) Gypsum crystals White/Eroded gypsum crystals Beautiful 2m stromatolite mounds (scale = 1m) Beautiful 2m stromatolite mounds 1-2m stromatolite mounds 1-2m stromatolite mounds Gypsum crystals Gypsum crystals

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162

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 5039 5040 5041 5042 5043 5045 5046 5047 5048 5049 5050 5052 5053 5055 5056 5058 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086

Description From top to bottom: - 1-2m Stromatolite mounds (in a circular feature/fold) - Packstone - White limestone 1-2m Stomatolite mounds 1-2m Stomatolite mounds 1-2m Stomatolite mounds 1-2m Stomatolite mounds 1-2m Stomatolite mounds Stromatolite mounds (<=1m) Stromatolite mounds (<=1m) Stromatolite mounds (<=1m) Stromatolite mounds (<=1m) 1-2m stromatolite mounds 1-2m stromatolite mounds 1-2m stromatolite mounds 1-2m stromatolite mounds 1-2m stromatolite mounds 1-2m stromatolite mounds >2m stromatolite mounds...almost as big as a vehicle (one picture) Stromatolite mounds Stromatolite mounds (one picture) Stromatolite mounds at the same level as the Hofuf gravel on top of the ridge (one picture) Stromatolite mounds at the same level as the Hofuf gravel on top of the ridge Stromatolite mounds at the same level as the Hofuf gravel on top of the ridge Stromatolite mounds at the same level as the Hofuf gravel on top of the ridge Stromatolite Mounds Stromatolite Mounds Stromatolite Mounds Stromatolite Mounds Stromatolite Mounds Gypsum crystals Columnar stromatolitic limestone on top of oolitic crossbedded grainstone and beachrock Stomatolite mounds Stomatolite mounds Stomatolite mounds in Hofuf gravels Stomatolite mounds Stomatolite mounds Stromatolite mounds Stomatolite mounds Stomatolite mounds Stomatolite mounds Stromatolit mounds Stromatolite mounds Stromatolite mounds Stromatolite mounds

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.90050 E50.90648

65

N24.90099 E50.90657 N24.90156 E50.90685 N24.90207 E50.90681 N24.90239 E50.90668 N24.90177 E50.90774 N24.90214 E50.90444 N24.90175 E50.90439 N24.90101 E50.90457 N24.89932 E50.90451 N24.90427 E50.90510 N24.90465 E50.90583 N24.89682 E50.91086 N24.89634 E50.91141 N24.89645 E50.91203 N24.89156 E50.90645

63 63 63 74 73 72 77 77 80 72 70 59 55 55 60

N24.89127 E50.90846

57

N24.94231 E50.88925 N24.94214 E50.88774

77 81

N24.94410 E50.88748

73

N24.94551 E50.88728

75

N24.94640 E50.88649

75

N24.94615 E50.88761

79

N24.94732 E50.88615 N24.94799 E50.88523 N24.94757 E50.88484 N24.94724 E50.88485 N24.91770 E50.90160 N24.92641 E50.89303

68 70 74 73 73 54

N24.92408 E50.89529

57

N24.91441 E50.90282 N24.91162 E50.90316 N24.91044 E50.90348 N24.90783 E50.90513 N24.88434 E50.89196 N24.88457 E50.89155 N24.88289 E50.89257 N24.88451 E50.90460 N24.88544 E50.90495 N24.88699 E50.90557 N24.88721 E50.90600 N24.88903 E50.90516 N24.88985 E50.90475

68 72 75 71 74 75 72 76 76 73 81 74 74

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163

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS #

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.89208 E50.90408

71

N24.87854 E50.89687 N24.88053 E50.90436

70 77

N24.88085 E50.90591

57

N24.91556 E50.90031 N24.91671 E50.90063

75 72

N24.87581 E50.90761

66

N24.87581 E50.90789

63

N24.91468 E50.89887 N24.91449 E50.89897 N24.91431 E50.89540 N24.91552 E50.89655 N24.91553 E50.89763 N24.87317 E50.90466 N24.87473 E50.90529 N24.87701 E50.90662

59 60 47 49 52 75 78 74

6005

Lithified aeolian dune (bottom) and inter-dune (top) sand, 38 metre long of the Upper Al-Nakhsh member (several pictures). Red, fine to medium grained sandstones with N24.89317 E50.90666 planar cross bedding and large-scale trough crossstratification. (Dill et al., 2007). Roots (one picture) are also common in dunes, along with water table marks.

66

6006

Unconsolidated red, fine to medium grained aeolian sandstone

N24.89305 E50.90930

63

6007

Sratigraphically 0.0m = Hofuf pebbles = Planar crossbedding (Reddish rock) 1.0m = Beach rock 2.5m = N24.91023 E50.89951 Coquina = White limestone = Red limestone

79

6008

5.0m = Gypsum crystals 6.0m = Gypsum crystal field

N24.91016 E50.89927

71

6009

Limit of the Gypsum crystal field 7.0m = Gypsum field

N24.91001 E50.89885

69

N24.91008 E50.89822

65

N24.91236 E50.90083 N24.91245 E50.90083

75 74

5087 5088 5089 5090 5091 5092 5093

5094 5095 5096 5097 5098 5099 6001 6002 6004

6010 6011 6012

Description Stromatolitic limestone. At same level as the stromatolite mounds. (One picture) Stromatolite mounds on a narrow ridge Stromatolite mounds Stratigraphically from top to bottom - Oncoidal Stromatolites - Gypsum crystals - Beachrock This is the base of the Middle Al-Nakhsh Stromatolite mounds Stromatolite mounds Burrows seen in a small limestone cliff immediately after a rain (picture taken in January 24th 2009). Animals such as echinoderms coud have made these burrows LLH stromatolites and centimeter-thick laminae in clayey marlstones of the Middle Al Nakhsh Member Gypsum crystals layer Upper Gypsum crystals layer Weathered columnar stromatolites Weathered columnar stromatolites Weathered columnar stromatolites Gypsum Crystals Gypsum Crystals Gypsum Crystals

8.0m = Gypsum Crystal limit 9.5m = Red limestone 10.0m = More gypsum Planar cross-beds in red sand Columnar stromatolites on the vehicle trail

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164

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

6013

Large cave. Transition between Middle to Upper AlNakhsh. As per Dill et al. 2007 article. Alternating red and grey siltstones, clays and marls formed in place of gypsum seams at the passage from the Middle into the Upper Al-Nakhsh Members. The only evidence for evaporitic conditions in the Miocene basin are some veinlets with selenite, which randomly intersect the massive red beds. Dissolution of highly soluble compounds (halite?) in the subsurface has given rise to dolines and caused a pervasive karstification at this site. A relative increase in relief on a rather small scale resulted from differential salt dissolution at depth and halokinetic processes along the northeast limb of the Dukhan Anticline. These processes brought about argillaceous mud flats and ground water induced calcretes instead of evaporites.

N24.87533 E50.90771

75

N24.87517 E50.90783 N24.87198 E50.90412

77 76

N24.90345 E50.90394

78

N24.92299 E50.89630 N24.92312 E50.89666 N24.91752 E50.90149 N24.91428 E50.90258 N24.90760 E50.90490 N24.90270 E50.90238 N24.88416 E50.89252 N24.88425 E50.89222 N24.88300 E50.89281 N24.89242 E50.90371 N24.87862 E50.89714 N24.87857 E50.89692 N24.87702 E50.90667 N24.92639 E50.89641 N24.92539 E50.89622 N24.91409 E50.89956 N24.91404 E50.90017 N24.91392 E50.89690 N24.91491 E50.89473 N24.88067 E50.89603 N24.89178 E50.90753 N24.89545 E50.91101 N24.89660 E50.91144 N24.89237 E50.90767 N24.90415 E50.90487 N24.90231 E50.90685 N24.90519 E50.90635 N24.90633 E50.90891

63 64 74 68 67 78 78 77 84 77 76 69 65 70 73 67 68 49 46 77 59 58 58 64 72 72 66 57

6014 6015 6016 6017 6018 6019 6020 6021 6022 6023 6024 6025 6026 6027 6028 6029 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042 6043 6044

Small cave. Red bed of the Upper Al-Nakhsh Gypsum field. Metre 76 in Dill's section Red aeolian sand (possibly a dune buried by Hofuf gravels) displaying cross beds and fossil roots (4 pictures) Packstone/Coquina Red Packstone/Coquina Gypsum crystals Gypsum crystals Gypsum crystals Columnar Stromatolites on the vehicle trail Gypsum crystals Gypsum crystals Beachrock Gypsum crystals Gypsum crystals Gypsum crystals Gypsum crystals Red limestone Crystals of gypsum Gypsum crystals Cross-bedded coquina Gypsum crystals - base of Middle Al-Nakhsh Gypsum crystals Gypsum Crystals Gypsum crystals Gypsum crystals Gypsum crystals Gypsum Crystal Ridge Gypsum crystals Gypsum crystals Gypsum crystal field Gypsum crystal field

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165

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 GPS # 6045 6046 6047 6048 6049 6050 7001 7002 7003 7004 7005 7006 7007

Gypsum crystal field Gypsum crystals Gypsum crystals Gypsum crystals

Position (Lat/Lon, WGS 84) N24.90693 E50.90620 N24.90156 E50.89622 N24.88838 E50.89853 N24.88928 E50.89366

Altitude (Metres) 66 86 73 74

Oncoidal stromatolite in a grey limestone (one picture)

N24.88822 E50.90513

83

Description

Red sand at the top of Upper Al-Nakhsh member (see picture of GPS point 7018) Trough cross bedding in a ooid grainstone, probably formed in a beach complex ? sand bar. Planar cross-bedding Planar Cross-Bedding Bedding Cross-beds and Beachrocks Trough cross-bedding which reflects scour and fill in a fluvial deposit. (one picture) Sequence Boundary shown by a white limestone which represents a sudden flooding. Metre 77 in Dill's section.

N24.91357 E50.90052 N24.87672 E50.90668

86

N24.87345 E50.90325 N24.87657 E50.90669 N24.87522 E50.90755 N24.88899 E50.89412

86 82 82 81

N24.88809 E50.89464

83

N24.87316 E50.90393

78

N24.88816 E50.90533

79

N24.89087 E50.90456

73

N24.88775 E50.90547 N24.87896 E50.89774

81 86

N24.91712 E50.90068

78

N24.87306 E50.90379 N24.92510 E50.89661

83 77

7014 7015

White limestone of the Abu Samra Member representing a Sequence Boundary / Red limestone at the top of the Upper Al-Nakhsh (one picture) White limestone of the Abu Samra Member representing a Sequence Boundary / Red limestone at the top of the Upper Al-Nakhsh (one picture) Wave ripples in sansdtone (one picture) Cross-bedded Beachrock Cross-bedded siltstone of the Abu Samra member overlaid by a cross-bedded conglomerate of the Hofuf formation Coquina White limestone below coquina

7016

White limestone below coquina, overlaid by Hofuf gravel

N24.92625 E50.89701

75

7018

White Limestone at the base of Abu Samra member (see N24.91357 E50.90058 picture)

72

8001

Pebbly conglomerate with Graded and Crossed beds, of the Hofuf formation sitting on top of the Middle Salwa. The "normal" loose pebbles of the Hofuf are covering it. The area of this feature is about 50 m2. (three pictures)

N24.94347 E50.94300

68

N24.88561 E50.90461

84

N24.92212 E50.89945

79

N24.88460 E50.89483

88

N24.88408 E50.89322

92

7008

7009 7011 7012 7013

8002

Pebbly conglomerate, laminated and cross-bedded of the Hofuf formation, sitting on top of the Upper AlNakhsh. The "normal" loose pebbles of the Hofuf are covering it. (one picture) Cross-bedded sandstone & pebbles

8003 01 - Geodetic Primary Geodetic Station G19 (one picture) Station_G19 02 - Falcon Falcon Hunting cash (one picture) Hunting cash

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166

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 1 Description GPS # 03 - Rounded Rounded structures (one picture). Could be of interest to structures archeologists Geodetic Station M21. Probably built in 1983 as per a 04 - Geodetic signed on concrete near by. The concrete base is worn Station M21 out and should be repaired 05 - Small Cave_Base Small cave at the base of a white limestone of the Middle Middle Al- Al-Nakhsh. Nakhsh 06 - Ali's Ali drives a red pickup truck and invited me for a coffee. Camp 07 - Saoud's In December 2008, Saoud (a bedouin) had a camp here Camp and he invited me for a tea 08 - Arrow Large arrow (800 metres long) pointing North-Northwest made of tires made of tires. Purpose unknown 09 - Shelter Old house foundation foundation

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.89754 E50.96350

82

N24.90030 E50.95935

89

N24.88775 E50.90613

75

N24.87216 E50.88811 N24.87147 E50.93225 N24.94256 E50.90767 N24.91912 E50.92847

47

At the time of this writing, it was possible to access Areas 1 and 2 from this point because they were still fixing the underpass that you see on the satellite image 10 - Possible (there was no fence); however, it is very likely that this & temporary access will be closed soon. Therefore, we recommend N24.86331 E50.90469 entrance to the reader to access Area 1 from GPS point 06 in area 2. Areas 1 and 2 Area 2 can also be accessed from the north by taking point 06 and then travelling west in order to take the underpass at this point 10 (Area 2 can also be accessed from the south at point 07) Khashm AlNakhsh

N24.87502 E50.90340

Note: Altitude readings are an approximation. Calibration of GPS before field work was not performed

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167

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 2 GPS # 1001 2001

2002 2003

2004

2005 2006

Description Limestone at the base of the green shale Echinoderms in limestone (second white limestone from the base of the cliff (or sabkha). At the sabkha level, can be seen the green clay at the base of the Middle Salwa (about 2 m thick). One picture This location shows a limestone with burrows and some echinoderms (Fibularia Damensis) This is an area of white to beige limestone. This limestone contains some echinoderms, especially in the southern corner Brownish to white limestone with [possible] weathered echinoderms (as shown in picture 2004-02). Very white limestone with some burrows and well preserved echinoderms (as seen in in picture 2004-01) = Upper part of Middle Salwa White limestone with corals and well preserved echinoderms sparsely distributed Flat surface of a hard and grey limestone occurring between two white limestones

Position (Lat/Lon, WGS 84) N24.85585 E50.89743

Altitude (Metres) -3

N24.82657 E50.89453

8

N24.81841 E50.89428

9

N24.82362 E50.89383

7

N24.81551 E50.88183

6

N24.81587 E50.88201

12

N24.81422 E50.88292

15

2007

Whitish to greenish/brownish limestone Two pictures

N24.81333 E50.88343

10

2008

A limestone with burrows Echinoderms (Fibularia Damensis). Formation is dipping to the north Echinoderms (Fibularia Damensis) Echinoderms (Fibularia Damensis) Echinoderms (Fibularia Damensis) Echinoderms (Fibularia Damensis). Formation is dipping South Echinoderms (Fibularia Damensis). Formation is dipping South Echinoderms (Fibularia Damensis). Formation is dipping South White Limestone. Formation is dipping to the North White Limestone White Limestone Packstone. Good prospect to find sirenian/dugong bones. Lots of echinoderms Limestone (No obvious fossils) Burrows in limestone Ironized Reef-like sessile foraminiferal colonies Small 1.8m cliff showing: The gastropod & bivalve layer / A limestone with burrows / White Limestone / Red Limestone Small bivalves and gastropods Burrows with Ironized Reef-like sessile foraminiferal colonies Top = Cross-bedded beach rock, Middle = Brown clay, Bottom = Greenish clay (One picture)

N24.81710 E50.87996

8

N24.85249 E50.91666

9

N24.84580 E50.91527 N24.85003 E50.91551 N24.84776 E50.91581

7 5 6

N24.85247 E50.91438

6

N24.85107 E50.91397

7

N24.85071 E50.91318

6

N24.85198 E50.91750 N24.84582 E50.91642 N24.84723 E50.91775

8 4 4

N24.85593 E50.90268

8

N24.85459 E50.91248 N24.85414 E50.89543 N24.80731 E50.88535 N24.80969 E50.88396

5 -3 8 6

N24.80956 E50.88782

6

N24.81034 E50.88780

5

N24.81309 E50.88233

3

N24.81437 E50.88146

6

2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027

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168

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 2 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

2028

The whole sequence at this point is better seen on pictures 2028_01 and 2028_02 Top: 0.3 to 0.8 m of beige limestone with burrows and some Ironized Reeflike sessile foraminiferal colonies (cap rock). These are better seen in pictures 2028_03, 2028_04, 2028_05, 2028_06 Bottom: 2.5m of brownish & greenish clay & marl interbedded with siltstone layers

N24.81378 E50.88043

1

N24.81392 E50.88006

2

N24.81581 E50.88093

4

N24.81581 E50.88037

8

N24.81615 E50.89471

6

N24.81710 E50.89418

6

N24.82171 E50.89404

6

N24.82292 E50.89408

2

N24.85231 E50.91389 N24.85127 E50.91391 N24.84957 E50.91278 N24.85154 E50.90272 N24.85006 E50.90508 N24.85314 E50.90344 N24.85162 E50.90201

8 7 6 11 13 13 11

N24.82722 E50.89517

5

N24.84869 E50.89985

4

N24.84805 E50.90087

7

N24.84913 E50.89928 N24.84740 E50.89929 N24.85628 E50.89940 N24.85209 E50.89684

2 4 8 6

N24.85083 E50.90124

3

N24.84914 E50.90149 N24.85541 E50.90196 N24.85321 E50.89588

4 6 -4

N24.85337 E50.89637

-2

N24.85517 E50.89633

-3

N24.85302 E50.89656

-5

2029

2030 2031

2032 2033 2034

2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056

One picture Top: 0.3 to 0.8 m of beige limestone with burrows and some Ironized Reef-like sessile foraminiferal colonies (cap rock). Bottom: 1m of brownish & greenish clay & marl interbedded with siltstone layers (the rest is buried with sand) 3D burrows in white limestone Top = Laminated limestone, granular to sandy / Bottom = Greenish clay (One picture) Small hill in the sabkha - Bivalves & Gastropods unit Limestone with limestone - White limestone - Red limestone - Greenish clay intercalated with siltstone layers Laminated siltstone capped with laminated limestone Beige limestone interbedded with siltstone layers. The underlying green clay displays some purple clay and white limestone layers . One picture Beige limestone interbedded with siltstone layers. The underlying green clay displays some purple clay and white limestone layers Limestone with burrows Limestone with burrows Limestone with burrows Packstone Bivalve & gastropod molds Packstone Lithology just below Packstone Beige limestone interbedded with siltstone layers. The underlying green clay displays some purple clay and white limestone layers Round Concretions (2 pictures) Beach rock at the top (1 picture). Stratified Limestone at the base (1 picture) Broken up coral reef material and burrows (1 picture) Broken up coral reef material and burrows (1 picture) Middle Salwa Nice section of the Middle Salwa Channels cutting through the clay sediments of the Middle Salwa Clasts in a limestone Laminated Siltstone, White limestone, Green shale Gastropod layer Limestone with burrows / Green shale interbedded with siltstone Limestone with burrows / Green shale interbedded with siltstone Limestone with burrows (base of which has a lot of clast material) / Siltstone / Green shale

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169

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 2 GPS # 2057 2058 2059 2060 2061 2062

3001

3002

3003

3004

3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 4001 4002 4003 4004 4005 4006 4007 4008 4009

Position (Lat/Lon, WGS 84) N24.85367 E50.92248 N24.85407 E50.92125

Altitude (Metres) 10 11

N24.85393 E50.92257

15

N24.84559 E50.91978 N24.84761 E50.92135 N24.84986 E50.92379

11 11 13

This is a very small area which displays stratigraphically the following (from top to bottom): A small clay mound about 1.5 metre high composed of: Green clay/Brown clay/Purple clay/Green Clay. The above mound rests on N24.81289 E50.88371 a small/restricted purple limestone surface with large (14 cm) bivalve shells (including Ostrea, better known as oysters, and Pecten which is better known as Scallops)

9

Description Echinoderms (Fibularia Damensis) White Limestone Flat area of "burrow" layer which is stratigraphically between the bottom and top limestone of the Middle Salwa Hill with the top limestone of the Middle Salwa Top limestone of the Middle Salwa Top limestone of the Middle Salwa

Purple limestone with large (14 cm) bivalves (including Ostrea, better known as oysters, and Pecten which is better known as Scallops) Bottom part of a clay section (see 3004 for upper part) Picture shows: Top: Siltstone (as cap rock): 0.3m Bottom: Green clay: 1.5m The purple clay with large bivalves (Ostrea and Pecten) that lies below the green clay is buried under the sand. Upper part of a clay section (see 3003 for bottom part) Picture shows the 2m section as: Top: Whitish to greenish sandy limestone with small 2.5cm bivalves (Papyracea) A green/red/green sequence of clays described as a Marine mudstone Top: Herringbone cross bedding in coquina with wave ripples at the surface / White limestone interbedded with brownish coarse limestone Coquina Coquina Red Clay area Sandy cover. Broken chunks of loose white & green oolitic limestone, some with shell impressions Sandy cover. Broken chunks of loose white & green oolitic limestone, some with shell impressions Coquina. One picture Red clay White Limestone Green shale Green shale Top = Holocene Beach deposits with shells / Base = Upper Salwa Columnar Stromatolites Columnar Stromatolites Blister stromatolites Columnar Stromatolites Tepee Stromatolites Columnar Stromatolites Crab/shrimp remains in Cross beds unit Blister Stromatolites. One picture Columnar Stromatolites

N24.81378 E50.88359

14

N24.82469 E50.89197

16

N24.82502 E50.89194

19

N24.82508 E50.89185

21

N24.83103 E50.89330 N24.82819 E50.89330 N24.81295 E50.88706

25 19 15

N24.84766 E50.89644

15

N24.84690 E50.89700

13

N24.82053 E50.89046 N24.85606 E50.89062 N24.85423 E50.89473 N24.85333 E50.89509 N24.85376 E50.89506

21 6 2 -1 -7

N24.81523 E50.87181

3

N24.84501 E50.89796 N24.84386 E50.88858 N24.82087 E50.88879 N24.82267 E50.88801 N24.82852 E50.89181 N24.82683 E50.88539 N24.82668 E50.88578 N24.82603 E50.88561 N24.83078 E50.89250

18 22 26 32 31 28 28 26 32

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170

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 2 GPS # 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021

Red Clay area Red clay area 3D burrows in limestone Red Clay Red Clay Limestone with burrows Red Clay Limestone with burrows Red clay Thick limestone with corals Coral/burrow remains in limestone White limestone with Corals and burrows.

Position (Lat/Lon, WGS 84) N24.81583 E50.88594 N24.81686 E50.88621 N24.81758 E50.88562 N24.82150 E50.87868 N24.83082 E50.89270 N24.83070 E50.89259 N24.80538 E50.88191 N24.80561 E50.88156 N24.80467 E50.87951 N24.85351 E50.89376 N24.82389 E50.88748 N24.84544 E50.89805

Altitude (Metres) 29 29 35 20 28 34 4 0 3 12 27 16

4022

Limestone with burrows exposed over a large flat area

N24.82114 E50.88452

32

4023

N24.82159 E50.88192

25

N24.82377 E50.88880

22

N24.84983 E50.89232

13

N24.84639 E50.89661

27

N24.84391 E50.90530

12

N24.84423 E50.90371

20

N24.84335 E50.88868

31

N24.81604 E50.88575

34

4032 4033 4035 4036 4037 4038 4039 4040 4041

Red clay area A 3m vertical cliff. Red clay at the bottom and coral/burrow remains at the top Top of Red clay layer Planar Cross bedding (1 picture), the top of which shows a beach environment (1 picture). Planar Cross bedding, the top of which shows a beach environment Planar Cross bedding, the top of which shows a beach environment Cross-bedding, Beach rocks and oolites: Top of Lower Al-Nakhsh Calcareous algae in limestone with well defined burrows. While no detailed study was performed on these samples, they are believed to be representatives of the red algae (Rhodophyceae), a type of algae belonging to the family Corallinaceae. These algae were important rock builders in areas with warm climate during the Miocene. Laminated siltstone beds Laminated siltstone beds Columnar Stromatolites Columnar stromatolites Columnar stromatolites Small circular stromatolites in limestone Tepee structures Red limestone with Planar stratified bedding above Top: Beige limestone - Bottom: Green clay

N24.81989 E50.88566 N24.82076 E50.88534 N24.80552 E50.88163 N24.81000 E50.87783 N24.81034 E50.88033 N24.81092 E50.87979 N24.80990 E50.88146 N24.82845 E50.89199 N24.82559 E50.89146

37 37 5 3 12 8 8 31 26

4042

Top: Grey and hard limestone - Bottom: White limestone N24.82568 E50.89142

30

4043

Top: Grey and hard limestone - Bottom: White limestone N24.82606 E50.89133

33

4024 4025 4026 4027 4029 4030

4031

4044 4045 4046 4047

Description

Top: Laminated siltstone - Middle: White Limestone Bottom: Red clay Red clay of Lower Al-Naksh. This clay is separated by the point immediately to the west by a white limestone (one picture) Large echinoderm taken from the white limestone about 0.30 metre from the top (2 pictures) Planar cross-bedding in grey limestone with small gastropods

N24.82595 E50.89113

35

N24.85619 E50.89088

8

N24.85561 E50.89138

11

N24.85512 E50.89168

15

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171

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 2 GPS # 4048 4049 4050

Position (Lat/Lon, WGS 84) N24.85539 E50.89154 N24.85601 E50.89120 N24.84836 E50.87254

Altitude (Metres) 10 11 -1

N24.84553 E50.87166

-3

N24.84639 E50.89276 N24.84793 E50.89166 N24.84407 E50.90445 N24.84394 E50.90464 N24.84983 E50.89153 N24.85083 E50.89169 N24.84299 E50.88864 N24.84242 E50.88939 N24.82911 E50.89160 N24.85283 E50.87081 N24.85367 E50.87048 N24.83038 E50.89179

29 34 18 20 22 30 29 32 35 2 -5 41

5022

LLH stromatolites and centimeter-thick laminae in clayey N24.84421 E50.90406 marlstones of the Lower Al Nakhsh Member (1 picture)

22

6001 6002 6003 6004 6005 6006

Disturbed gypsum crystals on hill top (1 picture) Coquina Three-Dimensional large Gypsum crystals (1 picture) Gypsum Crystals (1 picture) Undisturbed gypsum crystals (1 picture) Gypsum crystals

N24.84372 E50.89385 N24.84121 E50.88974 N24.84396 E50.90375 N24.84617 E50.89601 N24.84536 E50.89292 N24.84167 E50.88968

35 30 33 33 33 34

6007

This is the top of the hill; at this point can be seen several disturbed and undisturbed gypsum crystals Looking down in the quarry, owned by Qatar National Cement Company, can be observed the red limestone of N24.82328 E50.87992 the Lower Al-Nakhsh Member exposed by the mining activities. Only the side of the hill has been left intact in order to minimise the negative visual impact.

29

6008

This is the top of the hill; at this point can be seen several disturbed and undisturbed gypsum crystals. Looking down in the quarry, owned by Qatar National Cement Company, can be observed the red limestone of N24.82950 E50.89139 the Lower Al-Nakhsh Member exposed by the mining activities. Only the side of the hill has been left intact in order to minimise the negative visual impact.

39

6009

Gypsum crystals

N24.83043 E50.89164

41

6010

This is the top of the hill; at this point can be seen several disturbed and undisturbed gypsum crystals Looking down in the quarry, owned by Qatar National Cement Company, can be observed the red limestone of N24.83052 E50.89144 the Lower Al-Nakhsh Member exposed by the mining activities. Only the side of the hill has been left intact in order to minimise the negative visual impact.

44

6011

Gypsum Crystals

42

4051 5003 5004 5006 5007 5008 5009 5010 5011 5013 5019 5020 5021

Description Burrow & coral mounds/colonies (one picture) Burrow & coral mounds/colonies Blister stromatolites White limestone eroded in a north-south direction (one picture) Circular stromatolites (1 picture) Undisturbed Gypsum Anhydrite nodules Circular stromatolites, one metre in diameter Gypsum Gypsum Celestite crystals Circular stromatolites Circular Stromatolites (One picture) Oolitic Beachrock Oolitic Beachrock Beachrocks

N24.83118 E50.89103

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172

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 2 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

01 - Desert Roses

These are desert roses that do not require digging since they grow at the surface of the sabkha. They consist of large lensoid crystals of gypsum that have intergrown within the aeolian sand covering the sulphate-rich water table of the sabkha surface; sand grains are enclosed within the crystal lattice poikiitically. Given sufficient time, the crystals form a network of interlocking crystals so typical of the desert rose. Exposure of such a boxN24.82990 E50.89551 work of crystals to dessication at high ground surface temperatures results in their more distal extremities altering to white anhydrite (Glennie, 2005) While driving in this area, please be careful not to destroy the crystals with your vehicle. Also, it would be better that you do not collect these unique crystals since the area is very restricted.

8

02 - Flint

A piece of flint which seemed to have been worked at was found here. An identification by Qatar Museum Authority revealed that it came from north of Al-Khor and N24.80920 E50.88069 that it had most probably been in a fire since it showed some flakes at the surface

2

03 Seven_Dead_Camels

Seven dead camels

N24.82719 E50.89504

04 - Learaig Interchange This interchange was opened in early September 2008

N24.83719 E50.87208

6

05 - DW-14 Water well (one picture) 06 - Entrance to Area 1 In order to take it however, one must first travel to Abu 07 - Entrance to Areas 2 Samra (Qatar-Saudi Arabia border) 5kms to the south and 3 and make a U-turn 08 - Al Nafkah The official geographic name of our Area 2

N24.85253 E50.88038 N24.85170 E50.88749

2

N24.80528 E50.87403 N24.83785 E50.88877

Note: Altitude readings are an approximation. Calibration of GPS before field work was not performed

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173

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 3 GPS # 1001 1002 1003 1004 1005

1006

1007

1008

1009

1010

1011

1012

1013

1014

1015

1016

1017

1018

Description Limestone of the Lower Salwa. From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to sample 23 Top of Lower Salwa Loose Crab/shrimp remains Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong vertebra in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One small sirenian/dugong rib surrounded by few broken bones in a layer with lots of Large bivalves (Two pictures). Site discovered on March 27th 2009 Top Lower Salwa. Several sirenian/dugong ribs in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. Several sirenian/dugong ribs in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. (Several sirenian/dugong ribs in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. Several sirenian/dugong ribs in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. Several dugong ribs in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.71148 E50.88489

2

N24.72309 E50.87555 N24.75229 E50.91058 N24.76078 E50.91446

3 18 12

N24.76018 E50.91228

16

N24.76019 E50.91223

17

N24.76031 E50.91220

16

N24.76034 E50.91196

15

N24.76034 E50.91197

16

N24.76048 E50.91184

16

N24.76053 E50.91173

14

N24.76073 E50.91154

17

N24.76067 E50.91140

18

N24.76074 E50.91137

19

N24.76050 E50.91103

19

N24.76048 E50.91104

18

N24.76044 E50.91124

20

N24.76035 E50.91129

20

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174

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 3 GPS #

1019

1020

1021

1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052

Description Top Lower Salwa. Several sirenian/dugong ribs with one vertebra (one picture) in a layer with lots of Large bivalves. One vertebra is also located about 1m noth of the bones (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. Two sirenian/dugong ribs in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Top Lower Salwa. One sirenian/dugong rib in a layer with lots of Large bivalves (One picture). Site discovered on March 27th 2009 Several broken sirenian/dugong ribs. (One picture) Small broken sirenian/dugong rib. (One picture) Broken sirenian/dugong rib. (One picture) Broken sirenian/dugong rib. (One picture) A mound with a sirenian/dugong rib. (One picture) Several broken sirenian/dugong ribs. (One picture) Broken up sirenian/dugong ribs. (One picture) Several long and broken sirenian/dugong ribs. (One picture) One large sirenian/dugong rib with smaller broken ones. (One picture) A long sirenian/dugong rib. (One picture) One small sirenian/dugong rib. (One picture) One small sirenian/dugong rib. (One picture) One long broken sirenian/dugong rib. (One picture) Small broken sirenian/dugong rib. (One picture) Broken sirenian/dugong rib. (One picture) Broken sirenian/dugong ribs. (One picture) Small sirenian/dugong rib. (One picture) A small horizontal sirenian/dugong rib with a second vertically oriented. (One picture) At least four sirenian/dugong ribs. (One picture) Two long broken sirenian/dugong ribs. (One picture) A mound with lots of broken sirenian/dugong bones/ribs. One vehicle tracks can be seen cutting through the mound. (One picture) One sirenian/dugong rib. (One picture) One long sirenian/dugong rib. (One picture) One broken sirenian/dugong rib. (One picture) Several sirenian/dugong ribs. (One picture) Sirenian/dugong vertebra Small mound with broken sirenian/dugong bones Beach & intertidal environment of the Lower Salwa Vertebra of a sirenian/dugong Vertebra of a sirenian/dugong

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.76027 E50.91143

20

N24.76002 E50.91192

19

N24.76065 E50.91148

16

N24.76062 E50.91143

18

N24.76098 E50.90937 N24.76096 E50.90921 N24.76089 E50.90936 N24.76088 E50.90936 N24.76083 E50.90913 N24.76088 E50.90901 N24.76092 E50.90894

10 9 10 9 10 10 11

N24.75833 E50.90994

11

N24.75825 E50.91045

13

N24.75815 E50.91061 N24.75799 E50.91090 N24.75711 E50.91245 N24.75862 E50.91317 N24.75869 E50.91301 N24.75873 E50.91298 N24.75871 E50.91297 N24.75874 E50.91290

15 13 12 17 16 18 18 18

N24.75894 E50.91277

18

N24.75940 E50.91252 N24.76033 E50.91208

18 16

N24.76161 E50.91019

18

N24.76167 E50.90882 N24.76170 E50.90877 N24.76175 E50.90870 N24.76176 E50.90874 N24.76652 E50.90696 N24.76739 E50.90671 N24.73842 E50.90682 N24.76068 E50.91120 N24.76066 E50.91119

16 15 13 15 3 10 11 17 20

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175

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 3 GPS # 2001 2002 2003 2004 2005 2006 2007

2008

2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022

Description Large quantities of echinoderms on a folded/disturbed limestone Two pictures The whole hill is the white limestone of the Middle Salwa with lots of echinoderms. Crab/shrimp remains are also present White limestone of the Middle Salwa with lots of echinoderms. Crab/shrimp remains are also present White limestone of the Middle Salwa with lots of echinoderms. Crab/shrimp remains are also present Contact of the Middle Salwa with the Lower Salwa. Large bivalves are present Burrows at the contact of the lower and upper white limestones of the Middle Salwa White limestone at the base of the Middle Salwa with Crab/shrimp remains and shells Contact between the bottom and upper white limestone of the Middle salwa From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to sample 146 Top Middle Salwa with echinoderms From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to sample 138-139 Lots of echinoderms You need a special permission to go so close to the border Echinoderms with beautiful vertical burrows You need a special permission to go so close to the border Echinoderms with bivalves in limestone Crab/shrimp remains in very white limestone Crab/shrimp remains in very white limestone Top of Middle Salwa Crab/shrimp claw Crab/shrimp claw (one picture of the general area taken from this point showing the white limestone Crab/shrimp claw not shown) Few echinoderms Small bony remain of unknown animal (1 picture) One large bivalve in white limestone Small steep hill displaying arabic Graffitis Lots of burrows on a flat surface; some weathered on the flat surface, and some in three dimension detached from the limestone or still encrusted in it.

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.73273 E50.90253

6

N24.71804 E50.87780

18

N24.71575 E50.87892

16

N24.71553 E50.87882

19

N24.71806 E50.87840

14

N24.71756 E50.87730

14

N24.71103 E50.88309

9

N24.71111 E50.88292

13

N24.71071 E50.88247

17

N24.71876 E50.86486

12

N24.71822 E50.86405

12

N24.73797 E50.90027 N24.73792 E50.90047 N24.73755 E50.90088 N24.75367 E50.90705 N24.75274 E50.90671

21 18 16 17 16

N24.75305 E50.90547

14

N24.75337 E50.90653 N24.75272 E50.90681 N24.75240 E50.90607 N24.75074 E50.90604

16 19 17 18

N24.77362 E50.90508

16

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176

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 3 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

2023

Sirenian/dugong bones; some detached and broken-up, and some still in the rock. The greenish shaly limestone layer also displays large bivalves, large iron concretions, and few echinoderms. This site was discovered on March 20th 2009. On March 27th 2009 the author went N24.76911 E50.90646 back with a sieve and brush. One complete shark tooth was found in the sediments in which the bones lay. Several loose bones were removed together with two large ribs. Several bones still remain in-place.

12

2024

Patches of limestone with gastropods and small bivalves N24.80277 E50.88158

-1

2025

Top of green shale From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to samples 19-21

N24.71117 E50.88328

7

2026

Limestone From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to sample 14

N24.71106 E50.88323

9

N24.75052 E50.90723 N24.75226 E50.90990

15 19

N24.77235 E50.90627

6

N24.77157 E50.90690

10

N24.76963 E50.90679

12

N24.76862 E50.90615

13

N24.76891 E50.90723

9

N24.78071 E50.90372

10

N24.75795 E50.91332

21

N24.75801 E50.91350

19

N24.77255 E50.90576

9

N24.79116 E50.87196 N24.79206 E50.88154

-3 7

N24.79568 E50.88611

8

N24.71734 E50.87651 N24.71522 E50.87834

19 22

2027 2028 2029 2030 2031 2032 2033 2034 2035 2036

2037

2038 2039 2040 3001 3002

Layer of Large bivalves (Placuna Placenta) Green clay with large bivalves Green clay with large bivalves. The clay is overlaid by a white limestone Green clay with large bivalves. The clay is overlaid by a white limestone Green clay with large bivalves. The clay is overlaid by a white limestone Green clay with large bivalves. The clay is overlaid by a white limestone Green clay with large bivalves. The clay is overlaid by a white limestone Top Middle Salwa Some echinoderms, corals and seeds (one picture of the seeds) Beautiful mud shrimp claws, Bryozoa and 3D burrow remains Beautiful mud shrimp claws, Bryozoa and 3D burrow remains Wood fragments were found here. They were loos on the white limestione but had probably come from the layer above which is at the top of the Middle Salwa and represents a beach & intertidal deposit. The fragments are probably those of a species that lived in mangroves (one picture) White limestone with no special features Top of Middle Salwa Large teleost fish vertebrates still in the rock (three pictures) Contact of th Middle Salwa with the Upper Salwa Large bivales at the base of the Upper Salwa

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177

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 3 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

3003

Lots of large bivalves at the base of the Upper Salwa (2 pictures). Ostrea Latimarginata & Placuna Placenta

N24.71651 E50.87553

20

3004 3005 3006 3007

Green/red clay White limestone with burrows White limestone with burrows Top Upper Salwa

N24.71472 E50.87800 N24.71451 E50.87797 N24.71577 E50.87466 N24.71394 E50.87603

25 29 27 34

3008

Top of the green shale at the base of the Upper Salwa From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to sample 118

N24.71071 E50.88233

21

N24.71067 E50.88210

23

N24.70677 E50.87403 N24.70742 E50.87257 N24.71651 E50.86529 N24.73673 E50.89823

33 39 18 31

N24.75353 E50.90881

28

N24.75478 E50.90767

27

3009 3010 3011 3012 3013 3014 3015

3016

3017

3018

3019 3020 3021 3022 3023

4001

4002 4003 4004

Top of Upper Salwa (beachrock) with Molluscs From Cavelier's 1970 section of the Eastern flank of Hazm Mishabiyah it is equivalent to sample 114 Large bivalves at base Upper salwa Bone fragments Bivalves in rock and green shale limit Top Upper Salwa Green clay with large bivalves. The hill displays the complete Upper Salwa Section. Green clay with large bivalves. The hill displays the complete Upper Salwa Section. Quarry is operated by QNCC. This section shows the red clay overlaid by the white limestone of the Upper Salwa. The green clay below the red clay is seen in the smaller pit to the south. Packstone at top of Upper Salwa displaying cross and planar bedding (one picture) One possible shark tooth which was found loose on the white limestone (one picture). According to Otero et al 2001 however, this tooth could also be from a Hepsetidae which is a type of Pike fish that, strangely enough, lives in freshwater. White and grey bivalves, clams, burrows and gastropods in white limestone White and grey bivalves, clams, burrows and gastropods in white limestone White and grey bivalves, clams, burrows and gastropods in white limestone Coquina / packstone Green shale at the base of the Upper Salwa Crab/shrimp remains were found here together with two Diodon trituration/masticatory tooth plates each formed by a series of four or five slightly convex plates, most of which are well exposed along the trituration surface. Dugong bone remains on a small limestone mound (one picture). White shells also occur Bivalves Cross-bedded and rippled limestone

N24.74580 E50.89852

N24.79969 E50.87686

3

N24.78663 E50.88390

19

N24.78674 E50.88390

19

N24.78688 E50.88393

20

N24.78710 E50.88392

22

N24.75748 E50.88858 N24.79567 E50.88635

23 9

N24.68737 E50.86614

52

N24.78732 E50.89150

23

N24.71450 E50.87501 N24.71455 E50.87472

36 41

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178

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 3 GPS # 4005 4006 4007 4008 4009

Description

4023 5001 5002

Algo-mats Beachrock Crab/shrimp remains Oolithes Erosional disconformity One nicely preserved echinoderm still in the rock, probably an Opechinus or Psephechinus.... as per Kier (1972): Tertiary and Mesozoic Echinoids of Saudi Arabia, on plate 58, page 223 One Picture One nicely preserved echinoderm still in the rock, probably an Opechinus or Psephechinus.... as per Kier (1972): Tertiary and Mesozoic Echinoids of Saudi Arabia, on plate 58, page 223 One Picture Lots of burrows An echinoderm Agassizia powersi was found here Large mudcracks Coquina/packstone Some large and small bivalves at the base of a white limestone which overlays a green shale Some large and small bivalves at the base of a white limestone which overlays a green shale Some large and small bivalves at the base of a white limestone which overlays a green shale Some shrimps remains Large shells in white limestone From bottom to top: With limestone with large shells, blister stromatolites, columnar stromatolites The whole extensive grey surface displays weathered columnar stromatolites Red shale with some large bivalves Oolitic beachrock Shale. Samples 74-79 on Cavelier's section

5003

White limestone. Samples 57-60 on Cavelier's section

4010

4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022

5004

Oolites. Samples 44-48 on Cavelier's section Small stromatolite mounds Samples 31-32 on Cavelier's 5005 section 5006 Bulbous stromatolites DW-15 which was completed in June 2003 Ministry of DW-15 Water Municipal Affairs and Agriculture, Department of Well Agriculture and Water Research. Geodetic Station G18 Hazm Where Cavelier (1970) made one of his cross-section of Mishabiyah the Dam Qarn Abu Qarn Abu Wail: Official border with Saudi Arabia Wail

Position (Lat/Lon, WGS 84) N24.71484 E50.87319 N24.70967 E50.87852 N24.71072 E50.87935 N24.71446 E50.87354 N24.71179 E50.87605

Altitude (Metres) 36 38 40 41 35

N24.73696 E50.89690

38

N24.73687 E50.89687

45

N24.78686 E50.89181 N24.78716 E50.89166 N24.77993 E50.89339 N24.78019 E50.89373

20 22 29 34

N24.78757 E50.88860

29

N24.78733 E50.88865

28

N24.78662 E50.88853

30

N24.78813 E50.88665 N24.78530 E50.89062

24 32

N24.78519 E50.89061

33

N24.78455 E50.89099

32

N24.78601 E50.89430 N24.70991 E50.87978 N24.73918 E50.89618

31 46 45

N24.73943 E50.89595

49

N24.73938 E50.89585

61

N24.73940 E50.89562

56

N24.77853 E50.89008

45

N24.78866 E50.89534 N24.77874 E50.89017

46

N24.73725 E50.89551 N24.67308 E50.85954

Note: Altitude readings are an approximation. Calibration of GPS before field work was not performed

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179

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 4 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

3001

Top of Upper Salwa displaying nice broken chunks of the N24.93561 E51.20434 coquina. Molds of bivalves and gastropods can be seen

53

5001

Northern end of anhydrite Nodules ("Chicken wires" fabric) sector. GPS point 5007 is the southern end. Several pictures were taken between these two points

N24.83278 E51.11397

63

5002

Corals occurring in the layer above the anhydrite nodules N24.83118 E51.11561

69

5003

Corals occurring in the layer above the anhydrite nodules N24.83100 E51.11595

67

5004

Corals occurring in the layer above the anhydrite nodules N24.82915 E51.11730

66

5005 5006

burrows unidentified, but possibly the stem of a larger coral?

N24.83092 E51.11570 N24.83103 E51.11589

64 68

This location was named "Conical hill" by Whybrow in 5007 1987. Southern end of anhydrite Nodules ("Chicken N24.82720 E51.11839 Conical Hill wires" fabric) sector GPS point 5001 is the northern end. Several pictures were taken between these two points

64

Al Kharrarah

N24.90444 E51.17500

Tiwar al Huraythi

N24.80556 E51.09333

Note: Altitude readings are an approximation. Calibration of GPS before field work was not performed

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180

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 5 GPS # 1001 1002 1003 1004 1005

Description Limestone of the Lower Salwa. This rock contains less gastropods than the same layer to the south. Gas blisters on a bedding plane (one picture). They probably resulted from mat doming by gas escaping. Conglomeratic limestone (shaly clasts) White Limestone West dipping beds & beachrocks. The whole sector (as seen on the satellite picture) represents an intertidal environment

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.95014 E50.92679

44

N25.07397 E50.81006

7

N25.07282 E50.80974 N25.07253 E50.81271

6 11

N25.07318 E50.81288

14

2001

This is an important protected archeological site in SW Qatar called Jarr Umm Tuwaim (formerly known as "Bell rock"). Please respect its content. It is now fenced and should be entered only with permission from the Qatar Museum Authority. To learn about the archeology of this site, read our chapter 11.5 "A study of some bedouin rock-carvings in SouthWest Qatar" by Frances Gillespie N25.02769 E50.87760 The top of the site is composed of the limestone of the Middle Salwa. The echinoderm Fibularia damensis can be found, however, please do not collect there even if you have the permission from QMA to enter the site. You can collect from outside of the fenced area from the same limestone

2002

Lots of white shells (one picture) and 3D burrows

N25.06893 E50.81756

20

2003

Celestite nodules (http://en.wikipedia.org/wiki/Celestite), Iron concretions and lots of 3D burrows

N25.06889 E50.81736

18

N25.06859 E50.81817 N25.07739 E50.82270 N25.07646 E50.81991 N25.07189 E50.80963 N25.06922 E50.81269

22 34 30 8

N25.07194 E50.82625

33

N24.95071 E50.87850 N24.94970 E50.87677

46 43

N24.94978 E50.87667

43

N24.95127 E50.87567

41

2004 2005 2006 2007 2008 3001 3002 3003

3004

3005

Top of the Middle Salwa Top Middle Salwa Top of Middle Salwa White limestone gypsiferous green shale Coquina Gypsiferous layers Gypsiferous green shale Green clay at the base of Upper Salwa (one picture). This is part of the QNCC quarry Coquina in rippled limestone (wave structure) Coquina layer displaying mud cracks Calcareous algae in the coquina layer at the top of the Upper Salwa. While no detailed study was performed on these samples, they are believed to be representatives of the red algae (Rhodophyceae), a type of algae belonging to the family Corallinaceae. These algae were important rock builders in areas with warm climate during the Miocene. (One picture) Coquina level (top of cliff) White limestone (in cliff) Green clay (large area at bottom of cliff)

3006

Ripple marks (top) and Green & Red clay area (bottom)

N24.95869 E50.86899

36

3007

Coquina layer (top), White limestone cliff (bottom)

N24.95891 E50.86936

44

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181

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 5 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

3008

The whole section of the Upper Salwa, with the green clay at the base. Some shrimp claws were also found on a scraped surface at the base of th clay (where the N25.07247 E50.82385 vehicle is located in the picture) which represents the top of the Middle Salwa. This locality is part of the QNCC quarry

31

3009

Packstone at the top of the Upper Salwa. Some large rocks are getting detached from the cliff (one picture)

N25.00367 E50.85816

35

N25.00353 E50.85767

19

N25.07375 E50.82183

28

3010 3011 3012 3013 3014 3015 3016 3017 3018 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 5001 5002 Former camp

Base of the Upper Salwa displaying the Green shale and some large bivalves at the very base Very base of Upper Salwa with large shells. Green clay aslo occur few metres away Very large shells which have been scraped by the bulldozing activity and piled up on debris mounds along a quarry trail (one picture) Large shells from the very base of Upper Salwa Top of Upper Salwa displaying coquina/packstone Coquina/packstone Coquina/packstone Large shells at base of Upper Salwa Large shells at base of Upper Salwa Columnar stromatolites Columnar stromatolites Red clay. Bottom of Lower Al-Nakhsh Tidal Bar deposit (One picture) Ripple beds Ripple beds Red clay Red clay just below Hofuf gravel cover Anhydrite nodules on limestone mound (one picture). This is the first time that so much nodules are found in the Lower Al-Nakhsh member Columnar stromatolites Planar bedding in limestone White limestone cliff dotted with large anhydrite nodules One picture

N25.06712 E50.82069

27

N25.05808 E50.82634 N25.05657 E50.83163 N24.95357 E50.87803 N24.95272 E50.87600 N25.07739 E50.82187 N25.07772 E50.82247 N24.95365 E50.88325 N24.95376 E50.88285 N24.96125 E50.87559 N24.95650 E50.88190 N24.95607 E50.88241 N24.95591 E50.88241 N24.95321 E50.88190 N24.95978 E50.87395

30 45 49 42 35 36 61 61 49 60 73 78 52 47

N25.05731 E50.83159

52

N24.95460 E50.88183 N24.95418 E50.88363

64 70

N25.00565 E50.85830

43

Former camp

N24.95413 E50.86843

32

N24.98090 E50.87714

89

Geodetic Primary Geodetic Station G20 Station G20

One dead N24.95383 E50.88118 camel One pre- As described in Chapter 11.5 which deals with the islamic archeological site at our locality A5_2001 just 220 metres N25.02746 E50.87973 grave to the west Water Well See picture

N24.95755 E50.86706

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53 52 32

182

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 6 GPS # 1001 1002 1003 2001 2002 3001 01 Umm Bab

Description

Position (Lat/Lon, WGS 84) N25.08298 E50.81681 N25.08974 E50.81217 N25.10112 E50.80610 N25.18126 E50.78411 N25.08243 E50.81753

Top Lower Salwa Whit limestone in the Lower Salwa White limestone Echinoderms with crab remains Top Middle Salwa Planar/horizonta bedding overlaid by Cross-bedding (one N25.08201 E50.82468 picture) Rubbles of Eocene rocks N25.09694 E50.81533

Altitude (Metres) 23 11 9 6 31 41 22

N25.20319 E50.80443

Note: Altitude readings are an approximation. Calibration of GPS before field work was not performed

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183

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 7 Description GPS # 2001 Very top of the Middle Salwa Lots of echinoderms. The rock is a packstone formed 2002 with echinoderm debris Lots of echinoderms. The rock is a packstone formed 2003 with echinoderm debris 2004 Red limestone 2005 Red limestone 2006 Weathered coquina. Top of Middle Salwa 2007 Red limestone Weathered coquina. Ripple marks and cross-beds. 2008 Doline formation 2009 Red limestone 2010 Top of Middle salwa Top of Middle Salwa with Green shale patches of the 2011 Upper Salwa to the south 3001 Large broken-up bivalves with green shale above 3002 Large broken-up bivalves with green shale above 3003

3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 4002 4003 4004

Position (Lat/Lon, WGS 84) N25.07049 E50.91958

Altitude (Metres) 26

N25.07112 E50.91887

25

N25.07092 E50.91909

25

N24.97875 E50.97200 N24.97802 E50.97011 N24.97738 E50.96509 N24.98064 E50.96320

54 55 57 58

N24.98346 E50.96082

58

N24.98751 E50.95870 N24.99634 E50.95508

61 55

N24.99923 E50.95330

51

N25.12903 E50.88288 N25.12814 E50.88311

30 30

White limestone above green shale (one picture). A red limestone is also above the white limestone and in all the N25.02528 E50.96045 surrounding area; however it is not seen on the picture

50

White limestone. The field to the south is all red from the rocks of the red limestone which occurs above the white limestone Green shale overlaid by white limestone Green shale overlaid by white limestone Green shale overlaid by white limestone, overlaid by red limestone Very base of the Upper Salwa. Large shells can be observed Thin white limestone and green shale White limestone and green shale. Small bivalves, gastropods and burrows Red Limestone at top of Upper Salwa Thick white limestone. Only the top of the green shale is seen at the base Green shale White limestone and green shale below Weathered coquina with green shale below Green shale Upper Salwa Green shale with large bivalves Green shale with large bivalves White limestone with white bivalves Beachrock Cross-beds Some badly formed columnar stromatolites with 3D burrows

N25.02489 E50.96334

47

N25.05885 E50.92976 N25.06568 E50.93638

26 33

N25.07187 E50.92747

28

N25.07040 E50.91921

28

N24.98288 E50.95920

60

N24.98547 E50.96189

56

N24.98916 E50.96344

58

N24.98847 E50.96253

55

N24.98761 E50.95803 N24.99155 E50.95585 N24.99726 E50.95540 N25.03728 E50.95370 N25.03724 E50.95516 N25.06929 E50.91408 N25.07011 E50.91454 N25.04545 E50.93360 N25.10598 E50.90932 N24.98855 E50.96375

63 61 58 32

N24.99675 E50.95588

63

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28 26 39 37 64

184

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 7 GPS #

Description

Lower Al-Nakhsh at top of hill with Upper Salwa at 4005 bottom. The bottom unit is the green shale at the base of the Upper Salwa 4006 Beachrock 4007 Columnar stromatolites 5001 Oncoidal stromatolites 5002 Oncoidal stromatolites 5003 Oncoidal stromatolites 5004 Oncoidal stromatolites 5005 Oncoidal stromatolites 5006 Oncoidal stromatolites Consolidated and laminated red sand; very likely of windblown origin (one picture). The doline in which it is 6001 found is full of red sand resulting from the weathering of the consolidated rock Al This area was mined temporarily for the Hofuf sand in Huriyah 2009 Ti`s al Kiranah

Position (Lat/Lon, WGS 84)

Altitude (Metres)

N24.99614 E50.95448

54

N25.02844 E50.95028 N25.05750 E50.92200 N25.05756 E50.92280 N25.05799 E50.92142 N25.05783 E50.92164 N25.05910 E50.92238 N25.06598 E50.91751 N25.06439 E50.91764

45 28 28 28 29 30 25 24

N25.05814 E50.92185

30

N25.11667 E50.91667 N25.00970 E51.04367

Note: Altitude readings are an approximation. Calibration of GPS before field work was not performed

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185

The Miocene Guide of Qatar, Middle East (Dam Formation) Area 8 GPS #

Description

Position (Lat/Lon, WGS 84)

Altitude (Metres)

no points were recorded

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186

The Miocene Guide of Qatar, Middle East (Dam Formation)

11.7 – Links to all Picture Web Albums In order to access the available picture Web Albums, please click on the appropriate links below:

Area 01 Dam Formation pictures (190) http://picasaweb.google.com/leblanc.jacques/A1_DamFm?feat=directlink Miscellaneous pictures (4) http://picasaweb.google.com/leblanc.jacques/A1_MiscellaneousPoints?feat=directlink

Area 02 Dam Formation pictures (90) http://picasaweb.google.com/leblanc.jacques/A2_DamFm?feat=directlink Miscellaneous pictures (4) http://picasaweb.google.com/leblanc.jacques/A2_MiscellaneousPoints?feat=directlink

Area 03 Dam Formation pictures (87) http://picasaweb.google.com/leblanc.jacques/A3_DamFm?feat=directlink Miscellaneous pictures (1) http://picasaweb.google.com/leblanc.jacques/A3_MiscellaneousPoints?feat=directlink

Area 04 Dam Formation pictures (31) http://picasaweb.google.com/leblanc.jacques/A4_DamFm?feat=directlink Miscellaneous pictures None available. If a new album is created later, this page will be updated

Area 05 Dam Formation pictures (14) http://picasaweb.google.com/leblanc.jacques/A5_DamFm?feat=directlink Miscellaneous pictures (7) http://picasaweb.google.com/leblanc.jacques/A5_MiscellaneousPoints?feat=directlink

Area 06 Dam Formation pictures (2) http://picasaweb.google.com/leblanc.jacques/A6_DamFm?feat=directlink Miscellaneous pictures None available. If a new album is created later, this page will be updated

Area 07 Dam Formation pictures (3) http://picasaweb.google.com/leblanc.jacques/A7_DamFm?feat=directlink Miscellaneous pictures None available. If a new album is created later, this page will be updated

Area 08 Dam Formation pictures (0) None available. If a new album is created later, this page will be updated Miscellaneous pictures None available. If a new album is created later, this page will be updated

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The Miocene Guide of Qatar, Middle East (Dam Formation)

11.8 - Vertebrates of the Dam Formation in Saudi Arabia

Fig. 11.8.1 – Fossil localities of the Dam Formation in Saudi Arabia (some are briefly described below). The most western extent of the Miocene deposits is also indicated. The outline of the formation in Qatar is also shown. Note the Qarn Abu Wail locality striding the border between Qatar and Saudi Arabia; this locality is where H. St. J. Philby first found Miocene fossils in 1933. (Whybrow 1987b)

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- 188

The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig. 11.8.2: Stratigraphical section of the Dam Formation at locality 8 about 10 km N-NW of AsSarrar (26º 59’ 01’’ N; 48º 23’ 14’’ E). The maximum thickness of the Dam Formation in the AsSarrar area is only about 30 m, and important lateral changes have been observed. The presence of small vertebrates together with the associated bones of large mammals (Fig 11.8.3) with no sign of rolling and transportation point to a burial in low energy environment. A fluviatile environment is emphasized by the lithology, the presence of palaeocurrents, and the continental character of the fauna. All the sections observed in the As-Sarrar area display the intercalation of continental sediments into a marine series. This can obviously be considered as an indication of the relative proximity of the seashore. With regard to the fossil record, the palynoflora of As-Sarrar is mainly composed of groups such as Chenopodiaceae, which are on the whole indicative of open savannah grasslands. The reptile assemblage includes remains of testudinid Fig. 11.8.3: Rhinoceros skeleton in the fossiliferous bed of tortoises, boid and elapid snakes, and crocodiles. All suggest a locality 8. warm climate. The As-Sarrar avifauna evokes a tropical climate while the presence of ciconiiformes hints to the existence of trees. With regard to mammals, the As-Sarrar fauna is dominated by large mammals such as rhinocerotids and gomphoteriids, that is to say browsing forms. For their part, the rodents include representatives such as the ctenodactylids, gerbillids, and pedetids that would argue to a certain extent for a drier (but not necessarily arid) climate in a more open type of woodlands and bushlands. All the vertebrate localities of the Dam Formation in the As-Sarrar area are considered roughly contemporaneous. Evidences suggest a late Early Miocene age (16 Ma ± 1 my). The AsSarrar fauna is thus a MN5 equivalent. [Figures and text adapted after López-Antoñanzas (2004)]

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The Miocene Guide of Qatar, Middle East (Dam Formation)

Fig. 11.8.4: Schematic stratigraphic column for the Dam Formation of the Dammam Peninsula in Saudi Arabia (based on Weijermans 1999b’s sections at Jebel Midra Al-Janubi and Jebel Umm Er Rus). Fig. 11.8.5: Generalized topographic map of the Dammam Peninsula showing the location of Jebel Midra Ash-Shamali. Contour interval is 5 m. (Weijermans, 1999b) At Jebel Midra Ash-Shamali (Left), the basal Dam is exposed as a 0.5 to 1.5 m thick multicolored conglomerate containing boulders of Khobar Limestone (Eocene Dammam Fm) set in a sandy, argillaceous limestone matrix (see section above). The unit contains fragments of vertebrate bones and ungular teeth of Perissodactyl or Artiodactyl (Tleel, 1973).

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- 190

Abu Samrah

Miocene Dam Formation Qatar, Middle East A1_7001 = Trough cross bedding

A1_7006 = Trough cross bedding

A1_7009 = Sequence boundary

A1_7014 = Coquina Layer

A1_6005 = Lithified aeolian sand (Dune)

A1_6005 = Lithified Inter-dune & sand dune

A1_6005 = Roots/dikakas in lithified sand dune

A1_6005 = 38m long lithified inter-dune & sand dune

A1_6013 = Siltstones, clays & marls

A1_6002 = Gypsum crystals

A1_6029 = Gypsum Crystals

A2_6003 = Gypsum Crystals

A1_5005 = Oncoidal (SS-C) Stromatolites

A1_5060 = SH Stromatolite mounds

A1_5017a = Beach Rock

A1_5017b = Oolites

A1_5019 = Giant gypsum crystals

A1_5029b = SH / LLH stromatolite

A1_5093 = shrimp burrows in a limestone

A2_5022 = LLH stromatolites

A1_4008 = Microbial Mat “blister”

A1_4013 = Tepee Structures

A2_4026 = Planar Cross bedding

A3_4010 = Echinoderm Opechinus costatus

A1_4038= Myliobatis toothplate

A1_4018 & 4019 = Sirenian/dugong bones

A1_3017 = Herringbone cross-bedding

A1_3023 = Basal green & red shale

A1_3033 = Burrows

A1_3012 – Large bivalves

A2_3001 = Large bivalves

A1_2089 = White Limestone

A2_2032 = Limestone/shale

A2_2034 = Limestone/shale

A2_2050 = Channels – Tidal delta

A3_2036 = Mud shrimp claw (left), bryozoa (right)

A1_2010 = Echinoderms – Fibularia Damensis

A1_2115 = Large sirenian/dugong rib

A3_2023 = Shark tooth (found with dugong bones)

A1_1014 = Intertidal beach environment

A3_1050 = Intertidal beach environment

A1_1027 = Deformed ironized cross-beds

A1_1077 = Coral building-reef

A1_1078 = Coral building-reef

A1_1034 = Gastropod layer

A3_1051 = Sirenian rib in a bone “cemetery”

A3_1048 = Sirenian/dugong vertebra

Upper Al-Nakhsh

Middle Al-Nakhsh

Lower Al-Nakhsh

A1_4002 = Columnar (SH) Stromatolites

A1_4011 = Gastropod

A1_4009 = Crab remains

Upper Salwa

A2_3009 = Coquina

A1_3065 = Sirenian/dugong vertebrDH

A1_3024 = Coquina in rippled beds. Inter/sub-tidal

Middle Salwa

Lower Salwa

Credit: Stratigraphic column from Dill et al. 2007. Pictures and text from LeBlanc J. (2009)

Legend: A1_1078 = Location 1078 in Area 1

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