Underwater Archaeology Fieldwork San Vito Lo Capo, Sicily Italy
Archaeology fieldwork report Marco Roling Student number 1336991 – Course number 503123 Vrije Universiteit Amsterdam – Archaeology department – October 2006
Surveying and excavating a wrecksite in Sicily
Contents Introduction..........................................................................................................................2 Instituto Attività Subacquee (I.A.S.)....................................................................................3 The archaeological site .........................................................................................................4 Organization and operation of the fieldschool ....................................................................8 Administration....................................................................................................................8 Equipment ..........................................................................................................................9 Planned projects .................................................................................................................11 Personal note ......................................................................................................................11 Addendum 1: Personal dive log .........................................................................................12 Addendum 2: Photomosaic of the 6x6m grid ....................................................................13 Addendum 3: Autocad drawing of the site ........................................................................14 Addendum 4: Daily journals..............................................................................................15
Introduction After finishing a course in Underwater Archaeology in Leiden and some initial fieldwork in South Africa, I started to look for an opportunity to get real fieldwork experience in Underwater Archaeology. Since the focus of my study at the Vrije Universiteit of Amsterdam is mainly on Mediterranean Archaeology, I was hoping to combine this. In a book called ‘Archaeo-volunteers’ an Italian-based institute was mentioned which offered precisely what I was looking for1. This resulted in a visit to San Vito Lo Capo, Sicily, from August 23rd to September 14th. I participated in an Underwater Archaeology fieldschool organized by the I.A.S. The project involved surveying and excavation of a newly discovered site just outside the harbour. During the project the site appeared to contain leadshielded pieces of wood, amphoras from the Early Roman up to the Byzantine Era, and a great number of grindstones made of basaltic lava rock. This resulted in preliminary conclusions that at least artefacts belonging to different ships or shipwrecks are present on the site. Because these artefacts continue to emerge when excavating into the large seagrass areas, it is most likely that more of the cargo and maybe remains of the matching wreck is still buried under the seagrass and sand. The site thus gives the opportunity for more archaeological research to be performed in the next few years. Personally I gained good experience in working underwater, diving one or two times a day. The work included prospecting, labelling, installing a grid, measuring, drawing, operating the waterpump and airlift balloon and retrieving artefacts. This gave me a broad instruction and practice in Underwater Archaeology. I found it a great experience and a benefit for future projects. I experienced a very friendly and nice working atmosphere in San Capo Lo Vito. That’s why I would like to take the opportunity here to express my greatest thanks to Marcello Rocca, who organized and led this project in a very enthousiastic and sympathetic way with great practical knowledge and experience in Underwater Archaeology.
1
Archaeo-Volunteers, The World Guide to Archaeological and Heritage Volunteering, published by Green Volunteers di Fabio Ausenda, Milan 2003; See also the website at http://greenvolunteers.com/arkeo/
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Surveying and excavating a wrecksite in Sicily
Instituto Attività Subacquee (I.A.S.) The Instituto Attività Subacquee (I.A.S.) is a cultural association based in Palermo, whose purpose is the disclosure and training in the field of underwater archaeology. For a great number of years this association, in collaboration with the Superintendence of Underwater Archaeology of Sicily, organizes survey and excavation projects around Sicily. Some projects include a fieldschool in which participants are trained in practical stages and methodology of Underwater Archaeology. This fieldschool is supported by the European community, the Soprintendenza del Mare (the Maritime superintendence of Sicily), the provincial office for tourism of Trapani and the city council of San Vito Lo Capo2. It gives the opportunity to especially students, both Italian and from abroad, to gain practical experience in the Underwater Archaeology3. After finishing the course participants gain a license for Archeology Diver issued by the N.A.S.E., the National Academy of Scuba Educators4. Before actually going to Sicily, the objectives and work performed by the I.A.S. became more clearly to me by looking into last years summer campaign. The diving in 2005 took place near the Scoglio dello Scialandro, in Tonnara di Coffano a few kilometers to the Southwest of San Vito Lo Capo. They brought to the identification of fragment amphora material that can be dated to the classic era. Considering the huge quantity of material and the high risks of finding it deceitfully removed, the authorization of the Department of the Sea of the Sicilian Region was asked to carry out a first survey on the site. The ceramic material found in the site appeared homogeneous. The likely presence of undamaged amphora material and remains of the matching wreck, under the sandy sedimentation layers, could give further information about amphora typology and enlarge knowledge about the trade during the middle-republican age along the coasts off the northwest of Sicily. The constant clandestine stealing puts at risk, year after year, the integrity of the site and reduces the knowledge that we could achieve from a methodical digging and from an extensive study of the material. During the project a detailed survey was done on the site, artefacts retrieved and documented and a bathymetry map of the area was constructed5. The abstract of last years campaign shows that looting is becoming more and more a serious threat to the underwater heritage, especially because diving is an increasing recreational sport which takes divers easily down to a depth over forty meters. This means that it is important to research continuously underwater archaeological sites, assessing the way in which these sites need either conservation or excavation. This is the main driving force behind doing Underwater Archaeology projects around the island. The collaboration between the I.A.S. and the Superintendence plays a very important role for Sicily here.
2
See http://www.regione.sicilia.it/beniculturali/archeologiasottomarina/ See http://www.infcom.it:16080/subarcheo/ 4 See http://www.naseworldwide.org/ 5 In more detail this project is described in the publication issued in 2006, named: ‘Indagine Preventiva Sul Relitto “Scialandro 1” Relatione’ by Tusa, Rocca, Bonaiuto, Carrera, Amato. Also an abstract on this project and former projects is available on http://www.infcom.it:16080/subarcheo/attivita.html
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Surveying and excavating a wrecksite in Sicily
The archaeological site A fisherman discovered the site called ‘Roman site III west’ in June 2006. Searching for a good location for recreational fishing, an amphora was spotted. As the visibility of the water is usually very good, it is not uncommon to see clearly the seabed from the surface. Diving on the site made clear that the site contains pieces of wood sticking out of a large seagrass area and amphora pieces scattered around.
De site is in an area close to the harbour and easily accessible for fishing and recreational diving. The seabed is sandy and fairly flat, with depths between 17 and 18 meters, gradually sloping down to the north towards 20 to 22 meters. The seabed at the site is covered for about 20 to 30 percent with seagrass. The species of seagrass is Posidonia Oceanica, which grows only in the Mediterranean Sea. This type of seagrass has leaf bundles consisting of 5 to 10 leaves attached to vertical rhizomes. The leaves are broad (5 to 12 mm) and the length usually varies from 20 to 40 cm but may be up to 1 m (see figure 1). It grows slowly in clear water up to 60 meters depth and forms reefs of accumulating sediment. Simulation shows that a seagrass meadow of about 15 meters in diameter takes about 350 years to grow6. This is promising when considering a wreck disturbing the seabed and forming an artificial reef. On top of that a seagrass meadow can easily start to grow over the years. The meadow with the wood sticking out is at least 15 meters wide and more than 100 meters in length. Also during excavation of a small part of this seagrass meadow it became clear that at least two separate layers of seagrass are present. Just above the level of the sandy seabed there are remains of an older layer of seagrass, separated by a sand layer from the currently growing layer of seagrass. This means at least two stages, which suggests an age of the seagrass bank of at least 700 years. Obviously this is a very rough indication of the age the expected artefacts underneath the seagrass will at least have, Figure 1. Structure of seagrass because the growth speed is influenced strongly by factors Posidonia Oceanica such as sunlight, nutrients, current and depth.
6
See publication on http://www.seagrasses.org/handbook/european_seagrasses_high.pdf, page 15
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Surveying and excavating a wrecksite in Sicily
Especially in the first week a measurement grid was setup underwater. It was started alongside the seagrass area, to be able to secure the grid into the sand as much as possible and fairly level. The grid was pointed to the north, meaning that point D of the first 15x15m square ABCD was aligned to 0 degrees. In subsequent days another 4 squares were added to it in a northerly direction (see Autocad chart in addendum 3). The grid itself consisted of iron poles stuck in the ground, marked with a big floating label with a letter on it. The squares were delimited by connecting red-white tape between the poles. Prospecting in and around the grid was done on a daily basis to locate artefacts. Only classifiable artefacts were marked. This meant for example ceramics with distinct features like handles, rims or openings. The marked artefacts in and around the squares were labeled in situ, photographed, measured at least twice in relation to the grid and then finally retrieved to the surface for further cleaning and documenting. A master drawing was made on paper onto which all measurements were put down on a scale 1:50. Also the measurements were used to immediately create and maintain an Autocad image of the site.
Figure 2 Spatia amphora from the Byzantine period (5th – 8th century AD)
The first amphora pieces appeared to indicate a Greek-Roman provenance, but soon three types of ceramics made clear that also material from more recent periods were present at the site. The top parts of three very slender and long amphoras were found close together. These were classified as Byzantine Spatia amphoras (see figure 2)7. A vase-like artefact with originally four handles, covered with geometric lines decoration and glaze pointed towards a medieval provenance. Another strange ceramic piece was found also. It looked like an amphora, but the direction of the lines resulting from the turning of the pottery wheel did not match with the location of the mouth and handles of the amphora, which appeared to be on the side instead of on top. Also the neck was missing. This looked more like an amphora on its side. A digital reconstruction was made (see figure 3) to be able to assess what the complete object should look like. After this, a publication was found on Internet that showed a photograph of a complete specimen. A striking resemblance with the reconstruction made classification definite as being a so-called Bariletto. This type is found more around Sicily, for example at Trapani, but the dating is not quite determined8. Figure 3 Bariletto reconstruction by P. Mancuso 7 8
A photo of a complete Spatia can be found on http://h1.ath.cx/muvi/mubiz/foto/f42.html See http://www.archaeogate.org/subacquea/article.php?id=132 for details on the Bariletto.
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Surveying and excavating a wrecksite in Sicily
As the last square ILMN was being setup a few peculiar shaped stones were noticed lying around what appeared to be a natural rock formation. This was about 10 meters east of point N. At closer inspection the stones were about 50 cm long and typed as boat shaped, and one other was rectangular. Two pieces were taken to the surface for closer examination. The rock formation in itself looked more like two cylindrical pieces in a crossed position, concreted together with other objects. From that moment on the project focused on this area, around which another measurement square NPRS was setup and into that square a 6x6m grid was put down. This grid was divided by elastic bands into 36 individual square meters. During the course of the next two weeks, excavation was performed using a waterpump (See section on equipment). This cleared the sand away exposing more stone objects of various shapes. The 6x6m grid was photographed in detail and made accurate measuring possible. A photomosaic was created for an overview of the now so-called anchorage. The crossed pieces could have been originally tied together with rope, thus forming a stone anchor (see figure 4). But no similar anchors like this were known from literature.
Figure 4 The crossed ‘anchor’ in the center with labeled grindstones lying around
Sebastiano Tusa, head of the Sopratindenza del Mare of Sicily and professor at the University of Trapani, classified the stones as grindstones. He paid us a visit for a day, making a dive and inspecting the work and artefacts retrieved so far. He mentioned a similar case of a ship wrecked with a cargo of grindstones around Mallorca. This case was dated somewhere between the first century BC and the first century AD. But the Roman grindstones at that time usually had a round shape with a cut hole to stick a wooden turning handle in it. This shape was not found at the site here in San Vito Lo Capo. Maybe the found stones are even from an earlier period. He made clear that the stones were quarried most likely near Mount Etna on Sicily, as the texture and color of the basalt is very particular for that area. Also he claimed that the rectangular and boat shaped grindstones are to be used in pairs together, the first ones used as a base and the second ones to be used on top.
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Surveying and excavating a wrecksite in Sicily
Clearing away some seagrass at the west side of the grid exposed more grindstones and by the third week the excavation strategy was changed to focus on making a trench right into the seagrass (see photomosaic in addendum 2 for an overview of the grid and trench). This was done in order to see if more stones and preferably other cargo like amphoras turned up from underneath the seagrass. Best-case scenario would be actually stumbling upon the matching wreck itself. The trench proved to be a success as far as speeding up excavation in one direction. Every dive team extended the trench about 50 cm. But apart from other similar grindstones, nothing else was found, which was disappointing. Looking at the amount of seagrass taken away compared to the amount left in place, it is likely that the needle is still in the haystack somewhere. More work need to be done in terms of clearing a bigger area looking for the source of this cargo. The grindstones come in different categories and numbers. First are the square or rectangular shaped stones, of which there are only a few (see figure 5 left shape). Then the boat shaped, flat at one side and oval and round on the other (middle shape). There are a few dozen of these exposed. Then there are rounded or irregular shaped stones, which are also a few dozen. And then there is one unique piece, which was not found near the anchorage but more close to the wood. It is a grindstone, which is square with a straight opening in the middle and inward sloping sides (right shape).
Figure 5 The main regular grindstone shapes found at the site
The wooden beam sticking out of the seagrass is in two ways special. First because it is a piece which is angled and second because it has a clear trace of a lead sheeting covering that angle. This suggests a piece, which is used somewhere on the outside of the hull and maybe even on either bow or stern side considering the sheeting to cover the angle upwards. The wood was extensively documented during the campaign and the idea was to eventually cover it with sandbags in order preserve it for later research. The reason for not excavating the wood at this point in time was that this would take a major effort in terms of diving capacity and moreover exposing more of the wood would make it more vulnerable to erosion and deterioration. Also two lead bars were found together. The pieces were identical in shape and weight, clearly cast in the same mold. Their domensions are about 50x7x3cm. The pieces lack any writing or marking so it is extremely difficult to date them. They are more close to the wood than to the anchorage, so they possibly belong to another wreck.
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Surveying and excavating a wrecksite in Sicily
Organization and operation of the fieldschool Technical director of the fieldschool was Marcello Rocca, with prime technical assistants Paolo Amato and Dario Romano. Three others team members already participated during the last three years and therefore considered experienced. Other participants were mostly new to the Underwater Archaeology discipline. As an archaeology background was not required for participation, also for example students in marine biology and engineering were present. At the start of the fieldschool all participants taking the course of Archaeology Diver received a manual written by Marcello Rocca and titled ‘An introduction to the Underwater Archaeology’9. This gives a detailed overview of all relevant methods, techniques and equipment to be used underwater. The manual acted as a reference guide, but as the working days were quite busy, there was little time to study this in detail. It is written in Italian, which makes it less accessible for foreign students. This is a general remark as all administration was done in Italian as well as most of the communication. If future I.A.S. fieldschools really want to involve parties (like Universities, cultural heritage organizations, sponsoring companies) from other European countries, then I believe it will be a requirement to supply all the documentation in English and start to record all reporting and communication in English also. From a logistics point of view allowing a large group of people to join the project in order to complete an underwater photographing and video course was not a very wise decision. Although a lot of footage was shot underwater, which greatly attributed to the exposure of the project in various possible media, having so many extra divers around from the second week on sometimes made it too crowded above and underwater. It is good to have a few participants around who are in charge of photography, but only at times when this is really needed. I am sure that a core team (up to ten people) of only archaeologists would have encouraged more to share ideas, experiences and objectives. Simply because in a smaller group more time is available and people work even more closely together. In practice Marcello divided some specific tasks, like maintenance of equipment and drawing, among a few experienced people. But this sometimes led to the situation that some people were very busy and others at times less. In a smaller group the work can be divided more equally, as the span of control is better balanced. In the larger group like we had in the second and third week the busy people should have been more encouraged to recruit others in order to make maximum use of time and effort of everybody involved in the project. Administration The administration involved at first daily reporting by each participant individually. This is to collect as much information on the work performed as possible. Also it is essential that all participants actively consider and discuss their work. At least by writing about it this is encouraged which is very good. Daily reporting is especially valuable as small teams are diving together, each experiencing their own work and it is not always easy (also because of the language barrier above and below the water level) to discuss in detail the situation underwater. A lot of times there was a briefing before the morning dives and a few times also a debriefing at the end of the day, but not every day. Sometimes the diving schedule was written on a whiteboard but not always. I think it is important to brief and debrief the team as a whole every day and to make the schedule always visible so every one knows with whom to dive, what to do and where to put the equipment. 9
Issued by the NASE in 2001
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Surveying and excavating a wrecksite in Sicily
I found it very positive that dive teams were changed frequently, making sure that people are getting used to working together with other divers having a different level of experience and way of working underwater. Each day a dive log was recorded. A draft was maintained onboard and later on copied on paper into a standardized file. This was to ensure that all dives were within safety limits and also to calculate actual working hours underwater. Also each day all measurements taken underwater by individual divers were copied on paper into a standardized file. These measurements mostly involved the distances between grid reference points and the distances from specific artefacts to one or more of the reference points. These measurements were used later to reconstruct the site on a master chart on paper as well as in Autocad. Finally, each retrieved artefact was recorded in detail in a find administration. Because a computer network was installed and available for use in the dive school, I would advice to record the actual administration immediately electronically and save a printed copy each day in a paper file. This is to have an original and backup in different formats, and each to be used whenever suitable. Also it is good to appoint each day one person being responsible for the administration of the diving, the measurements and the finds. Each participant gains experience in that way having to make sure that the administration is complete and accurate. Equipment Underwater Archaeology requires specific equipment and as the divers go out to sea, it is important to have the right equipment onboard. Logistics is something to be much aware of. Equipment falls in different categories. First there is personal equipment. Dive gear was for most people personal property and therefore their own responsibility. Work equipment consisted standard of a drawing tablet, a measurement tape of 20m and a net for retrieving artefacts. Next was equipment suitable for a particular kind of job. When a dive team went to setup grid poles, then amongst the things to take down were the poles themselves, labels, a hammer, measurement tape, red white tape. When photographing was the aim of the dive, then obviously a camera was needed. So each task required specific equipment. I found it not always obvious where to find this equipment and in case of maintenance who was responsible for that. In the hurry of preparing a dive team for the scheduled job, it would be good to have some central place in the dive school where material and equipment is stored and put back after use. This makes immediately clear if something is missing or broken or out of stock. It was good that teams were encouraged to make sure that they brought their equipment with them at the dive and also taking it back, being responsible for the equipment. Finally some equipment is for general use, like the boats, engines, filling station, compressor and waterpump. This equipment is vital, because if it fails the whole project is affected and slowed down. In the best case all this equipment should have a backup available to replace the original when out of order. But because of proper maintenance and only few people operating this equipment, in practice a backup system was not needed. It is a risk though throughout the project. Sometimes it is important to get extra briefing on the use of equipment. The example that I give here is about the actual working of the sorbona (the Italian name for the waterpump). This device is meant to suck sand away by means of pumping water through a hose, thus creating a flow of sand and water. It’s not the same as an airlift, which pumps air down which expands while going up, thus creating an upward flow. The waterpump instead takes in water close to the surface, accelerates it through a compressor that is installed on a small rubber boat, and pushes it down to the seafloor through a water hose pointed backwards. Attached to 9
Surveying and excavating a wrecksite in Sicily
the first water hose is a second hose, pointed forward. The front of that hose is the mouth through which the sand is sucked away. When I was diving and the hose got clogged, my buddy and me first did not know what to do about it. Luckily someone at the surface saw us struggling with the device and came down to help us. Already minutes had passed of our valuable dive time. As the suction power of the pump is limited, it happens frequently that the suction hose gets clogged with sand and seagrass. If this occurs then this hose must be detached from the water hose, and lifted upwards by one diver while the other diver shakes the hose to try and empty it. This procedure, starting with detaching the hose, was not explained and demonstrated properly before. The sorbona was not very powerful and got clogged regularly as said before. Using it resulted in slow progression of the excavation. Also the range of the device was limited, so the sand taken away accumulated just outside the 6x6m grid. A sudden current could have put back the sand immediately. An airlift device would have been much more effective, but this requires more space and attention from an operational point of view.
Figure 6 Sorbona installation and operation underwater
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Surveying and excavating a wrecksite in Sicily
Planned projects The director and his assistant of the museum of Constanza, Romania, joined the project in order to gain experience in organizing an Underwater Archaeology project. Constanza is a city at the Black Sea, which dates back to Roman times. Extensive land archaeology projects are already taking place in Romania and around Constanza, but Underwater Archaeology is a completely new discipline here. As Romania will officially join the European community in 2007, the timing is good to investigate possibilities for Underwater Archaeology projects here. As it is not a very rich country collaboration with other countries seems vital to be able to make a real start. As the I.A.S. is experienced in Underwater Archaeology projects with the support of the European community, both Constantino and Catalin were eager to learn and experience all which is needed to startup a project themselves. They expect that the Black Sea contain numerous shipwrecks of era going back as far as the Archaïc period. The 250 kilometers of Romanian coastline is considered to be virtually unexplored. Ideas were exchanged to think about setting up a European project for Underwater Archaeology in which at least Italy and Romania are involved, but which is also open to other European countries for participation. Before the end of this year a proposal is planned to be ready for parties interested. In my opinion this means also an opportunity for Dutch Universities like the Vrije Universiteit of Amsterdam to be in some way involved. Students can do research and fieldwork on maritime topics not only in the Mediterranean Sea area but maybe also in the Black Sea area.
Personal note Working for the first time in an Underwater Archaeology project, I learned a lot in three weeks time. It took my dive experience beyond the stage of fundiving towards really working underwater. I am aware of the fact that the conditions during this project were ideal from a fieldschool point of view. The depth was within decompression limits, the visibility superb, and the almost lack of current and swell were very comfortable. I was glad that I was able to participate in all major archaeological tasks, such as prospecting, drawing underwater and above, operating the sorbona, measuring, excavating, operating the air balloon and labelling. Having to perform a task within given time limits with other divers made me aware that working underwater starts by a preparation onshore. It is important to agree on the order in which to do the different tasks, who takes what equipment and what to do in case of setbacks. Some points of improvement I have made already earlier on in this report. But overall I believe that the fieldschool was professionally organized and led, with sufficient and suitable equipment. Major time and effort was put in systematically and methodically recording the site through measurements, drawing and photography. As the grindstone objects were found and the strange anchorage, it turned out that excavation would focus on this particular area, hoping to find more cargo and a matching wreck. I think that this was the most obvious decision to make, instead of exploring the wood at the other side of the site. I really would like to return to Sicily next year to participate again in any project organized by the I.A.S., as I share great memories and friendship with people who participated in this fieldschool in San Vito Lo Capo. I recommend the I.A.S. as a professional organization for anyone who would like gaining practical experience in Underwater Archaeology.
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Surveying and excavating a wrecksite in Sicily
Addendum 1: Personal dive log The following personal dives were recorded: No 1 2 3
Date 24-08 26-08 27-08
Start 11:08 10:37 10:49
End 11:50 11:17 11:26
Min. 40 40 37
Depth 36.0 31.4 41.0
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
27-08 28-08 28-08 29-08 29-08 30-08 30-08 31-08 1-09 1-09 2-09 2-09 4-9 4-9 5-9 5-9 6-9 7-9 7-9 8-9 8-9 9-9 11-9 11-9 12-9 12-9 13-9
16:09 10:05 16:07 10:05 16:11 10:02 16:11 9:44 9:54 16:03 9:49 16:03 10:02 15:58 12:13 15:56 9:58 12:20 17:00 12:47 17:17 10:59 10:10 14:31 9:46 14:45 9:56
17:01 10:54 17:05 10:53 17:05 10:55 17:05 10:31 10:38 16:52 10:40 16:52 10:54 16:46 12:53 16:35 10:37 13:08 17:48 13:30 18:13 11:58 11:12 15:21 10:46 15:40 11:07
52 49 57 47 52 47 52 47 43 48 51 48 52 47 40 39 39 43 48 43 55 59 61 50 59 54 70
16.8 17.4 17.5 16.7 17.6 17.6 17.6 17.5 17.7 17.7 18.2 17.7 17.6 17.9 17.6 17.6 17.7 17.7 17.7 17.7 22.8 21.4 17.7 17.5 17.5 17.6 17.7
Stops 3 min 5 m 3 min 5 m 3 min 10 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m 3 min 5 m
General activity Fun dive Fun dive Fun dive Prospecting Grid set-up Grid setup Drawing Drawing Grid setup Grid setup and drawing Grid set-up 6x6 setup and prospecting Prospecting 6x6 setup and drawing 6x6m set-up Clearing seagrass Clearing seagrass Installing sorbona 6x6 excavation 6x6 excavation 6x6 excavation Retrieving artefacts 6x6 excavation Prospecting Retrieving artefacts Trench excavation Trench excavation Trench excavation Trench excavation Trench cleanup
Total bottom time: 23 hour and 37 minutes
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Surveying and excavating a wrecksite in Sicily
Addendum 2: Photomosaic of the 6x6m grid
Created by P. Mancuso with photos shot on September 14th, 2006 13
Surveying and excavating a wrecksite in Sicily
Addendum 3: Autocad drawing of the site This Autocad drawing of the site shows the grid and the artefacts identified by numbers. Also the two anchorages are visible, the most northerly being the one where the excavation with the 6x6m grid (shown as the I-II-III-IV square) was performed.
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Surveying and excavating a wrecksite in Sicily
Addendum 4: Daily journals During the fieldschool notes were kept on a daily basis to keep track of personal work performed and to understand the general project objectives and progression. Working hours were from 8:00 AM until usually 18:00 PM or sometimes even later. Only Sunday was free for making an excursion or for relaxation. Saturday 26 August 2006 Marcello gave us (David, Luca and Marco) an introduction to the measurement strategy that we will use during the site excavation. He stresses out that it is very important to think out and practice everything on land before going underwater because the time underwater is limited and each team should know exactly what to do when and where. The measuring techniques will be explained below using the following sketch of the general situation of the archaeological site:
D
C
B
G
H
F
E A
The rectangle ABCD is made up of four reference points, which will actually be poles into the seabed. Poles are roughly set using a compass. Each pole is marked visually by a small floater attached to it and also with a label containing a capital letter. These four points will be exactly copied onto drawing paper with a scale 1:100 (this is obviously done on land). To be able to copy, after putting the poles on the seafloor the following measurements need to be taken underwater: AB, AC, AD, BC, BD, CD. The square EFGH is a fixed frame (6x6m) divided into 36 individual square meters. The frame is laid on the seafloor on top of part of the site that needs measuring. The individual square meters are identified by A1..F1, A2..F2, … , A6..F6. To be able to copy the exact position of the square onto the drawing with the ABCD reference points, the following measurements need to be taken underwater: AE, AH, BF, BG, CG, CF, DE, DH. Important is to notice that all points are chosen in a way that the angle between for instance DH and AH is between 80 to 90 degrees. This makes measuring errors overall as small as possible. After putting the 6x6 frame on the seafloor a smaller drawing grid of 1x1m is put onto one of the square meters of the bigger grid (for example onto B3). The smaller grid is divided into 100 individual square decimeters for detailed sketching of the artefacts on the seafloor. The individual square decimeters are identified by A1..L10 (Only letters A, B, C, D, E, F, G, H, I, L are used. The four corners of the 1x1m grid are identified as α, β, χ and δ (alpha to delta). After putting the 1x1m frame onto the seafloor this needs to be leveled using a leveling device. This is especially important when working on a slope, like in this case. After leveling the artefacts are drawn on a paper grid (scale 1:10), prepared on land. After drawing the artefacts are labeled in situ. The artefact list, named besides the drawing grid, contains the numbers of the labels and the position in the drawing, for example: ROM06-1234: B5; ROM06-1235: G1 When the diver is drawing the artefacts, it is very important that he/she is positioned exactly above the artefact and not in an oblique position. Also the diver must not touch the grid to prevent de-leveling of the grid. The diver will take at least five depth measurements using a sounding lead and ruler. The measurements will be taken on the grid corners alfa till delta, and also in the exact middle of the grid. If there are any interesting artefacts, then also the center of these are measured in the same way. For example: Alfa – 20cm; Beta – 22cm; Gamma – 21cm; Delta – 24cm; ROM06-1234: B5. Sunday 27 August 2006 In the afternoon the team made a first trip to a new site, which will be explored in the next weeks. It is not far outside of the harbour in a northwest direction. This first prospection was to mark to most obvious artefacts underwater will little numbered floaters, so they can be easily found again next time. This first dive showed that the water is very clear and clean with good
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Surveying and excavating a wrecksite in Sicily visibility up to 25 meters. There are big areas of about one meter high seagrass (in Italian called ‘posidonia’) on a fairly flat sandy seafloor. There are some small rocks and big pieces of amphoras and other ceramics dispersed around. This site is interesting because of the known presence of at least two pieces of wood sticking out of a big seaweed area that also is a little bit higher than the surrounding seabed. Also the orientation of the wood pieces is the same. This makes a wreck site probable. Back at the dive school Marcello gave us a briefing on the project administration with forms for dive logging, measurement logging and daily worksheets. By tomorrow the archaeological team will consist of ten people (Marcello, Paolo sr, Dario, Paolo, Raffaele, Laura, Luca B, Luca R, David and Marco). The first important thing is to set up a measurement system on the seabed so all artefacts and possible structures can be related to that. The team will perform this in the next days. Monday 28 August 2006 Start of day 8:15 End of day 20:00 Meteo Sunny, 29 degrees Briefing Objectives are to start making a measurement grid on the seabed for the new site (not named at the moment because we don’t know obviously what to expect to find). This means hammering poles down into the sand, attaching a letter to it, measuring all sides and diagonals of the squares and put signal tape between the poles to make the squares easily visible. There will be four teams, each going down after the prior team has returned. The reason is that the next team will continue the work of the prior team and so on. The grid will consist of three connected square areas 15m by 15m (see sketch). The side ADFH points to the north. The grid will be setup parallel to the big seagrass area with the woods sticking out. Work performed Teams were formed as follows: David, Paolo, Marco; Luca, Luca, Dario; Raffaele, Laura; Marcello, Stefano We rehearsed at the dive school the way in which we would swim to minimize effort. Also we agreed on the various tasks so underwater it is clear what to do in the limited dive time that is around 30 to 45 minutes. We first set point A about 15 meters from the edge of the seagrass area. This first point was used to align the other points. D came 15 meters to the north of A, then we determined B by measuring 15m from A and 21m from B. After this we determined C the same way to complete the first square. This makes the intended square not completely square, but this is not relevant because each pole is a point of reference by itself for future measurements. Other points were setup accordingly to complete the grid. Letters were attached and signal tape. In the afternoon we made accurate measurements of all sides and diagonals and back at the dive school we transferred all data to a master drawing of the site. It appeared that one measurement for point G was missing, so this will be taken tomorrow. Also EF is a bit short, namely 14.4m but we leave it as it is. The poles are in place with a letter attached to it. The grid is nicely aligned to the north. Not all measurements are taken of point G, so this to be taken tomorrow. The grid is transferred to a master drawing plan of the site on a scale 1:50. Tuesday 29 August 2006 Start of day 8:15 End of day 19:30 Meteo partially cloudy, less wind, 27 degrees Briefing [1] Objectives are to map and draw the seagrass around the grid for the master chart. Also the wood pieces need to be measured trilaterally. Point G must be measured. A start is to be made for making a photomosaic. [2] Objectives are to move the anchor to the other end of the site, extent the site with points IL and prospect and draw this new area. The reason is that Marcello during his dive noticed that going north there are still many pieces of amphoras visible and so the site is not fully in focus still. Work performed [1] In the morning the teams were formed as follows: Laura, Marco; Raffaele, Luca R; Luca B, David; Paolo Laura and I agreed on the way to draw. We decided to each start at one end of the grid and draw the squares one by one. In this way we would both make a full drawing and we could compare them before transferring the average to the master chart. We focused on the outline of the seagrass, after that the big rocks and most obvious artefacts like amphora. It’s difficult to assess distances between the various points of interest during drawing. Important is to hover at a constant level about 6-8 meters above de seabed. I found it a good way to start from one corner and first for a few minutes form an overview picture before actually starting to draw. Also it is good to look at the square from different angles to check visually the dimensions. We drew not only the grid itself but also some surrounding area. Obviously it is important to think about setting up the grid
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Surveying and excavating a wrecksite in Sicily on the drawing tablet before entering the water. It should be just big enough to cover the drawing area, otherwise this leads to improvisation underwater. Always make sure that both sides of the tablet can be used for drawing. Team 3 finished measurements, attached the missing signal tape and went further on prospecting. David and Luca found two lead ingots of rectangular shape (~50x7x3cm), which were not measured trilaterally, but al least marked with a floater. They are close to EF and lying against each other. Back at the dive school Paolo made part of the Photomosaic with Photoshop, with remarkable good result. Important is to convert the pictures to black and white and to adjust the size so that they can overlap. Also here it is vital to hover at the same level while making the photographs. [2] In the afternoon the teams were formed as follows: Dario, Stefano; Paolo, David, Luca B; Raffaele, Luca R; Marco, Laura The anchorage was moved underwater to the north. The grid was extended as planned and prospected. Laura and I drew the area GHIL. Then the anchorage place (outside the grid) became focus for prospection as Marcello and Paolo sr found stone objects, apparently cut with great care in squares and boat shapes (see sketch). They are not worn very much and especially the boat shapes are nice (we noticed about nine of them close together. Laura and I made a drawing with some measurements of the boat shape. The square ones (we only saw two) are about 60x60x10cm. Topside view
Frontal view
14 cm
50 cm
19 cm
Grid is setup now and extended to ABIL. The seagrass outline is drawn roughly and transferred to a master chart. Two lead ingots are traced and numerous stone cut objects around the anchorage place. Other artefacts are tagged with a floater to find them again later for measuring and recovering. Wednesday 30 August 2006 Start of day 8:15 End of day 20:00 Meteo Sunny, a few clouds Briefing The site is to be extended to the north with another square ILMN. Also the rock boats and wood need more prospecting. Two rock boats will be lifted for further examination. Work performed Before diving my team (Laura, Luca B, Marco) rehearsed the various working steps to be performed underwater. During the dive we setup point N and roughly measured IL, LN and IN. The visibility was about 6-8 meters that slowed down the work. Due to excessive swimming and anxiety Luca ran low on air and went up before Laura and Marco. We managed to put up red white tape between LN, so point N is easily visible now. In the afternoon my team (Laura, David, Marco) setup the other point M with accurate measurements LN, IN, IM, MN, ML for transferring this later on onto the master chart. Visibility was around 15m so much better. The red white tape was put between IM and MN, so the extension of the grid is finished now. Additionally the measurements from L and N to the new anchorage were taken. Finally Laura and Marco made a quick drawing of the new square. The grid is extended with MN now in a northerly direction. Also this area is drawn and prospected. Marcello and Paolo have lifted two of the boat shaped rock objects. More of these objects are found in the vicinity of the anchorage place. I put a request for information on boat shaped rock objects on the Internet community of Subarch, as we don’t seem to be able to find any reference to publication about such objects. The site possibly needs to be extended tomorrow again with MNOP and the 6x6 grid will be installed on the seabed. Thursday 31 August 2006 Start of day 8:15 End of day 20:00 Meteo Sunny, a bit of wind Briefing From point N to the East a square needs to be setup around the anchorage place. This will be NPRS, with diagonals around 20m. Also prospection and photographing will take place north of MN. Work performed
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Surveying and excavating a wrecksite in Sicily The first dive my team (Laura, Luca R, Marco) managed to setup the new square NPRS in good cooperation. Red white tape was put between the poles and the following measurements were taken by me on a slate: LP = 8.91m, NP=10.45m, NS=18.32m, PS=14.50m, PR=19.65m, NR=14.78m. In the afternoon logistic work was done at the dive school. An iron box was put together, to be used for collecting and moving seagrass or other material. The compressor was tested, as it will be used for the pump to take sand away. Also labels were made from old plastic containers. These labels will be used to mark artefacts underwater, before measuring them and retrieving them. Grid is extended with NPRS now, finalizing the measurement system underwater. Marcello and Paolo found a few amphoras near NPRS, important for dating the site. The following GPS coordinates of the site were taken: South anchorage is N38 11.152 E12 44.235, North anchorage is N38 11.198 E12 44.233. Marcello took artefact SP17 from the anchorage place, thinking at first that it was an iron concretion, but it turned out to be a piece of ceramics. Friday 1 September 2006 Start of day 8:15 End of day 19:00 Meteo Sunny, no wind Briefing The 6x6 grid will be put down and assembled underwater around the anchorage place. Also some important amphoras will be labeled, measured and retrieved. Other prospection will be done outside NPRS. Work performed The four pipes that form the sides of the 6x6m grid were lowered down from the boat onto the seafloor. My team (Raffaele, Luca B, Luca R and Marco) went down and picked up the pipes one by one out of the seagrass and moved them to the anchorage place. Here it was assembled but without the elastics being stretched which will mark each square meter. The grid will be moved to its exact position later on. A few artefacts were labeled, measured to the closest points P and R and retrieved in the plastic box. One artefact is awkward as it looks like an amphora, but the opening and ears seem to be made after the belly of the amphora was closed at both sides. This makes it look like a horizontal container instead of a traditionally vertical shape. The amphora is incomplete, as it is only part of one side, with the mouth and one ear attached. After cleaning the amphora shard, Paolo made a reconstruction composition drawing using Photoshop, to assess what the complete object should look like. Raffaele eventually found a publication on it by searching for something like ‘amphora without neck’. This publication is found on www.archaeogate.org/subacquea/article.php?id=132. It is called a bariletto shaped amphora and more examples are known around Sicily. It seems that this type is dated to the Byzantine period (5th-8th century AD). The photo in the article matches perfectly the reconstruction made earlier in Photoshop. One of the other amphoras, being a rather long and slender type with a pronounced neck and mouth, is being typed by Marcello as a Byzantine Spatia (see sketch). This is conformed later on when I found on Internet a picture and description of this type, which matches nicely to the found artefact. See http://h1.ath.cx/muvi/mubiz/foto/f42.html for this article and another at www.sportesport.it/amphorae12.htm. So the first idea is that we are dealing here with a Byzantine wreck site. But other artefacts, like the rock boats and typically GreekRoman amphora pieces point also to other periods. It is possible that the site consists actually of more than one wreck or cargo for various periods. On land the stratigraphy of the site is a good indication of the timeline involved, but in the sea obviously all periods can be aside on the seabed or fully mixed, because of the highly dynamic environment. Saturday 2 September 2006 Start of day 8:15 End of day 19:30 Meteo Sunny Briefing Prospection will take place in northerly direction and also the outline of the seagrass is to be drawn to the north. The 6x6m grid will be put in its exact position, secured with poles and labeled. Work performed In the morning I started drawing the outline of the seagrass from NPRS to the north. This was difficult because this was outside the grid reference points. I used my compass to find the cross points of the extended lines LN and RS and IM and RS and then draw the area in between. After that I went further north, but the drawing grid on my slate was too small, so I had to
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Surveying and excavating a wrecksite in Sicily improvise on the back starting another drawing. A good marking point was also that I saw the other team measure and retrieve artefact SP44. I put this into the drawing to be able to reconstruct actual distances. The area further north is also quite flat and sandy, with some big amphora shards. Big areas of seagrass come into view. Back at the dive school I quickly transferred the drawing onto the master chart, still having the situation underwater clear in mind. In the afternoon my team (Paolo, David, Marco) placed the grid in it’s final position and secured it around the anchorage place. One side is about half a meter up resting on the seagrass that starts here and stretched out to the west. Poles hold the sides of the grid and each corner was labeled (Roman numbers I, II, III, IV were used for this). The corners were measured exactly to the surrounding points NPRS. Finally the elastics were attached making it a grid of 36 square meters. After this Paolo made a first photomosaic of the 6x6m grid. The 6x6m grid is setup and secured. The anchorage itself looks like two large cylindrical shaped stones that are crossed and concreted together with other artefacts. It is a strange conglomerate. Possibly the crossed objects are indeed an ancient anchor. It seems likely that they are closely related to the boat shaped rock objects and similar objects of different shapes (round, square, rectangular) lying around the anchorage. A large surrounding area is prospected and some 45 artefacts are retrieved now for documenting and conserving. Monday 4 September 2006 Start of day 8:00 End of day 19:00 Meteo Sunny 28 degrees Briefing Objective is to take away all seagrass within the limits of NPRS, starting from within the 6x6m grid. This is because excavation of the 6x6m grid will start as soon as possible. The iron box was already put down on the seabed yesterday, so this can be used to put the seagrass into. The seagrass is to be taken away completely from the roots up. Work performed The iron box was already filled with seagrass. My team (Paolo, David, Marco) first started to move to box to an open patch in the seagrass to the NE to clear it. We used a parachute-like balloon for this, which lifts the box when enough air is blown into the balloon. When the box was being cleared, the balloon got loose and floated unfortunately to the surface. Paolo went up to retrieve it again. Visibility was extremely good today, no current and no thermocline as the last three days. We moved the box back and cleared some seagrass patches. The seagrass has a fairly fine root system going 20 to 50cm in the sand. When the sand is shaken out of the root system, the roots are easily broken off, and the seagrass plant can be removed. The leaves that grow in pairs from a central growing tip can be around a meter in length and are about one centimeter wide and only a few millimeters thick. The seagrass grows also horizontally in the topsoil thus extending in all directions. In the afternoon we cleared seagrass again. The area NPRS is almost clear from seagrass, so excavation can start tomorrow. Tuesday 5 September 2006 Start of day 8:00 End of day 20:00 Meteo Sunny Briefing A large group of young people doing a photography course has joined the project, which makes it a lot more difficult to organize and manage the dive teams. It gives the opportunity to document every item and activity underwater and above, which is a great contribution to the excavation, but on the other hand it imposes some impact on the efficiency of the diving also. Anyway, to manage this, dive teams were formed into archaeological dive teams and into photography dive teams, which were not to interfere with each other, but at times to complement. Only objectives from an archaeological point of view will be mentioned hereafter in this journal. Today the pump (named in Italian the ‘sorbona’) will be made operational underwater, to start excavating around the anchorage (see sketch). Before that the 6x6m grid will be drawn as it is now. Work performed The sorbona consists of a compressor, installed on a small rubber boat at the surface, and hoses attached to it. One hose with a filter (to prevent jellyfish and other material being sucked down the hose) takes seawater in and the compressor is used to pump the water down a long and flexible hose towards the seafloor. Here the water is accelerated through a smaller pipe into a second attached hose. This hose has an open mouth at the front and at the back a net is attached. The accelerated water stream is pointed backwards into the direction of the net, so that at the front a suction force is created which takes away the sand and shells and possibly shards, which will all be caught in the net. There are a few problems with this system. The power of the compressor is rather low, so the suction force at the mouth of the hose is not very strong. Second, the net which catches the sand, shells and artefacts fills up every ten minutes or so, and
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Surveying and excavating a wrecksite in Sicily one diver needs to rock the net in order to get the sand out and give way to the water stream again. As the reach of the hose is only about 10 meters, the sand taken away is just outside the 6x6m grid. Last but not least the hose itself gets clogged at least once a dive. If this happens then the hose must be detached and two divers, each at one end, hold the hose vertical to shake out the blocking sand. These problems make that in every dive up to one third or more of the dive time is lost due to operational activity instead of actually excavating. There are four subsequent dive teams now available (each two to three people) for excavation. Each team excavates for 30 minutes until the next team has arrived underwater. Debriefing Marcello gave a debriefing at the end of the day. This is important as the group has increased to about 25 people now and everyone must be aware of the work that needs to be performed. The following points were made clear: Big artefacts, like the stone objects, should not be interfered with, only the surrounding sand must be taken away, so the object is lowered by its own weight The excavation level must be equal throughout the grid. It’s important to prevent that individual pits are formed. Stratigraphy is important. Each team must consist of one person operation the mouth of the hose and another checking the net, making sure that the sorbona keeps working properly. Also the current must be checked to that the sand does not float back into the working area and also the position of the net should not interfere with the 6x6m grid. Wednesday 6 September 2006 Start of day 8:00 End of day 19:15 Meteo Sunny, windy Briefing Continue excavation of the 6x6m grid. Also documenting artefacts. Today professor Sebastiano Tusa will pay a visit to the project. Work performed Due to improvements made by Paolo to the compressor, the power is increased and the sorbona works better now. New stone objects appear in the westerly direction. In the afternoon I got a brief drawing course by Marta, after which I have drawn three artefacts. Marcello and Sebastiano took an inspection dive on the site. Debriefing Professor Tusa is head of the Underwater Archaeology department of Sicily and also lecturer at the University of Trapani. He is responsible for all Maritime Archaeological projects around the island. He has a staff of about forty people with four archaeologists and technicians and divers. A lot of times they need to take action on reported cases of looting, illegal diving, locations where fisherman’s netting is obstructed and so on. They do fieldwork usually from April till October (But during the tourist season of August) and have four concurrent projects going on. See also the website of the ‘Sopratindenza del mare’. Our project in San Vito lo Capo is supervised by him and so he was paying a visit, making a dive also, to inspect the excavation underwater and assessing what we found so far as to what kind of artefacts etcetera. Summary of the Tusa speech: It looks like there must be a wreck that went down with a cargo at least consisting of grindstones of different shape. Two types are likely to be used together, namely the boat shaped ones upwards with the rectangular ones downwards. The basalt the stones are made of is most probably quarried in the Etna area on Sicily. Only three antique quarries are known in Italy, all having their distinct color and texture. A first estimation for the grindstones is 1st century BC – 1st century AD. This is because a similar case is known for a ship with grindstones that sank near Mallorca, which is dated as mentioned here before. The Byzantine amphoras do not match with this, but they can be from another cargo and so far they are only a few pieces, unlike the grindstones which are now about thirty labeled. The two cylindrical objects, which are crossed at the anchorage, can indeed form an antique stone anchor, where the two pieces were held together by rope. First assessment looks like the pieces are also made of the basalt rock. Further investigation on what is underneath the pieces is needed to really find out the nature and use of the pieces. Advise is also to try and measure and weigh the pieces as to say whether they can be used as anchor in the first place and second how big a ship would carry such anchor. The pieces of wood that are about 40 meters away from the anchorage can also belong to a different structure, possibly a wreck. The big piece sticking out of the seagrass area is peculiar. It looks like an angled piece, also with traces of lead sheeting. It could be the stern side of a keel. It would be wise to take a sample for dating it dendrochronologically of with C14 techniques. It is an interesting site that needs a lot of further research. Marcello adds to this that excavation needs to continue outside the 6x6m grid into the adjacing seagrass area at the northwest. This is to see whether the grindstone cargo continues in that direction, and hopefully we stumble upon other cargo or even a wreck itself that is expected to be very near the exposed cargo at the moment.
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Surveying and excavating a wrecksite in Sicily Thursday 7 September 2006 Start of day 8:00 End of day Meteo Sunny, no wind Briefing Objective is to extend the excavation outside the 6x6m grid (but in NPRS), clearing away the seagrass and level the sand to the already excavated part. Also artefacts are to be retrieved from EFGH and GHIL. Work performed Because of the number of dive teams the planning extends and it takes a couple of hours for me to be picked up for the dive. In the meantime I have been drawing an amphora on land. The dive was not very productive, as Davide and I did not know immediately what to do when the sorbona hose got clogged. This was the result of a lack of instruction on the working of the sorbona. Also it turned out that the compressor ran out of fuel at the surface that we did not notice underwater. Also the retrieval chest was forgotten so another team went also to excavate instead of retrieving artefacts. In the afternoon my team (Claudia, Vera, Marco) went to retrieve artefacts from the areas EFGH and GHIL. There were not that many left marked with a floater, so we also picked up other pieces, which later on turned out to be of little interest as they were not part of the mouth, neck of base of the artefact. This is crucial as to classify the artefact later on. Three floaters numbered 62, 21 and 69 were retrieved. The following pieces were labeled and measured as follows: 16SP L4.50 H12.10 100SP L14.60 H 7.05 48SP F5.42 H12.90 98SP F6.29 H8.53 94SP H4.64 on the line HL As 98SP consisted of two pieces later 61SP was taken for the second piece with the same measurements as 98SP. Marcello thinks about flipping the 6x6m grid towards the northwest, in order to start excavating and documenting that part. More cargo is expected. As Roman grindstones of the period 1st century BC till 1st century AD are mostly round for circular grinding, he thinks it is also possible that the stones are actually a couple of centuries older. Marcello also stresses out that each team is responsible for taking and bringing back equipment and that this should lead to any delay in performing the dives. Everybody should act responsibly during the work. During the debriefing I realized that I did not bring up the measurement tape. The last thing I recalled was that I used it at the last measurement between H and L. This makes clear that it is very important underwater to stay concentrated and bring back everything that was taken down in the first place. I reported it to Marcello, who was very understanding. I told him to look for it tomorrow at the next dive. Friday 8 September 2006 Start of day 8:00 End of day 20:00 Meteo Sunny, no wind, 31 degrees Briefing Continue excavating to the NORTHWEST of the 6x6m grid. Also more photographing, videoing and prospecting to the North. Work performed Davide and I went as the last dive team of the morning. The sorbona worked well. The seagrass can be removed fairly easy when the sand is taken out of the root system. Another four grindstones are slowly being exposed now. In the afternoon I went for a prospection dive with Paolo sr. We swam in a 30 degrees angle (being NNE) straight. The seabed gradually slopes down towards 20 meters after about 40 meters swimming. The bottom is flat and sandy with small patches of seagrass and very much larger parts. The seagrass holds sand together mounting up to about a meter above the surrounding area. We found floater number one on it’s own with no reference to an artefact. Possibly left from another much earlier survey. We found a few big parts of the side of wide amphoras. Also a large oval shaped basalt stone likely to belong to the same cargo as the stones near the anchorage. This one was about 20 meters to the North of the anchorage alongside the seagrass. We also found a rounded piece of granite, about the size of twice the palm of the hand. This peculiar rock was mainly of a white mineral, but also with various intrusions of a shining metal. This is possibly something like pyrite. Because of the solely nature of the piece we questioned if it was there for a natural reason of that it was cut by man and lost at sea. We left it in situ, quite near the earlier mentioned oval basalt rock piece. The first photography team going down retrieved the lost measurement tape. It turned out to be drifted away towards GH. To the north the number of exposed artefacts become quickly less. This does not prove anything by itself though.
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Surveying and excavating a wrecksite in Sicily
Saturday 9 September 2006 Start of day 8:15 End of day 19:15 Meteo Partly cloudy, some wind Briefing Retrieval of remaining artefacts of the areas ABCD, CDEF, EFGH. Especially the two lead ingots and the jar with three ears are focus of retrieval. Marcello now wants to have a compass bearing shown in the photo, to be able to see the orientation of artefacts underwater. Work performed I prepared a slate with a compass onto it and a place to write down the number of the piece to be photographed. Our team started the dive OK (Patrick, Luca B, Marco, Alessandro) going for the ingots first. The retrieval box was put aside the grid. The photographing and measuring of the ingots took some time, after which things became confusing as Luca took the slate and went to photograph another piece with Alessandro, leaving Patrick and me behind. Now the team was split up and no coordination was possible between the photographing and the measuring. Eventually Luca ran low on air and took off to the anchor line to surface, surprisingly carrying one of the lead ingots, which was put in the retrieval box earlier. Patrick had a jacket that did not inflate. After the dive we had a big discussion on what went wrong in this dive. But after we had set everything straight, with Marcello moderating the argument, we could shake hands and end it. First of all, we should have surfaced all together when Luca indicated only having 50 bar left. Second, we made clear that improvising to a large extent without proper communication is also not good. Al last, swimming around with a lead ingot that was to be easily retrieved with the box was not done. This was a learning experience for all. We retrieved floaters 8, 78 and 56. In the afternoon we did not dive, but made more labels and did other drawing stuff. Andrea arrived, a restorator from Peruggia. He wants to speak to Tusa about conservation work in the underwater archaeology. Unfortunately Tusa already left last Thursday. Andrea gave a small practical course on conservating the amphora piece that has a three-word inscription on the inside of the mouth. This piece is very fragile and the outside is fixed with glue like solution applied slowly in a number of layers. Monday 11 September 2006 Start of day 8:00 End of day 20:00 Meteo Sunny, no wind, later that day cloudy and distant thunder Briefing Objectives are to startup the sorbona again, excavate underneath the anchorage to see what is there, clear more seagrass, label grindstones and photograph them. Work performed Paolo and I went first down to attach a rope to the sorbona hose, to be lifted up by someone at the surface. After that we moved the iron box filled with seagrass using the balloon about 30m and emptied it. The fishing line which I had removed days before from the anchor line and had dropped into the seagrass again turned up attached to Paolo’s suit. I removed it again, this time making sure to drop it far away and onto the sand to be visible at any time. We picked up loose seagrass lying around the NORTHWEST edge of the 6x6m grid and put it into the emptied box. In the afternoon the sorbona hose was clogged with sand again. I was stupid to use my regulator to try and send up air into the hose to speed up the clearing of the hose. Instead, my regulator was filled with sand and I spend about 20 bar clearing it and stopping the free flow of air. After diving Paolo, Luca and I tried to know more about seagrass itself. Paolo as a marine biologist had some literature on this and a teacher to consult. The seagrass grows depending on factors like current, water temperature, sunlight, depth, minerals, and soil type. It is not possible to assess how old the seagrass is and how it builds up in layers with sand in between. The speed of growing is impossible to measure, so the grindstones underneath can be any age. Marcello thinks that the excavation should progress now into northwest direction as under the cleared seagrass we find still the same cargo. We still expect to find other types of cargo excavating to the northwest. The cargo is the main focus now, as it is still a very unique complex. The wood further to the southwest is also interesting, but at the moment of minor importance. Its excavation would expose more, starting deterioration because of hydrodynamics and microorganisms. As all equipment is now based at the anchorage it seems more appropriate to research that, because it is not clear what the anchor like pieces are and how old the grindstones are. This seems very legitimate reasons. But the biggest problems are: • Excavation is slow, because of the limited speed of the sorbona. • The precise direction in which to search the other cargo and the wreck is not fixed • Each team of divers is working on the seagrass edges, each in another direction
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Surveying and excavating a wrecksite in Sicily It is not very worthwhile theorizing about how a ship might go down here. In my opinion the only option is to choose a direction in which to excavate into the seagrass area and then make a trench. Focus of all divers is then the same, speeding up the process of taking away sand and seagrass in a specified direction. Another advantage is that a profile will be formed on the sides, giving insight into the thickness of the seagrass root system, the thickness of the sand and maybe even the slope of the underlying natural rock. This idea of a trench is shared with Marcello, who at first is afraid that a small trench will collapse because of sand that falls in from the side. But in the end it is decided and shared with the rest of the group that tomorrow we will start to dig straight into the seagrass, about a meter wide. It’s estimated that it must be possible that one dive team will progress about half a meter during one dive. We hope to trace the origin of the grindstone cargo in that way back to the ship it came from. Using the sorbona under the anchorage is stopped as the risk is involved that the anchor like pieces will only sink more into the sand. It is exposed enough for now. Tuesday 12 September 2006 Start of day 8:00 End of day Meteo Cloudy Briefing Objectives are to start making a trench into the seagrass in one direction to follow a trail of grindstones, hopefully to find other cargo. Other team will document and draw the big piece of wood. Work performed Being together with Paolo in the first dive team, we started by clearing the iron box and then to excavate a new trench. This was started halfway between the corners III and VI of the 6x6m grid and into a northwest direction. We made it about 1m to 1.25m wide and we traced three more grindstones at the same level as the 6x6m grid. As there was no current the sand and dust created an underwater fog, making the visibility around the trench very low. But the subsequent teams managed to create a trench about 2m – 2.5 m long, focusing on taking away the seagrass. The seagrass root system become thicker when entering the seagrass area more and more, so it is harder to remove. In the afternoon there were some complaints of too many people being in the water at the same time, photographing the excavators. But with low visibility this is sometimes confusing as to whom to pay attention to. Technically the creation of the trench worked well, but still no other types of cargo were found, which was disappointing. The sorbona works but is still not strong enough to speed up the excavation. Marcello estimates the number of dives until the end of this campaign and the number of people available. This is because tomorrow I will have my last dive and also the two Romanian guys are leaving on Thursday. Officially the fieldschool ends Sunday. Anyway, it’s good to start consolidating the site as it is. This means that the next days the sorbona will only be used to cleanup the site. Then the 6x6m grid will be drawn and photographed for the last time, the 6x6m grid will be flipped over so that the trench can be mapped accurately. Also the wood piece will be covered with sandbags en thus preserved against further deterioration. Wednesday 13 September 2006 Start of day 8:00 End of day 19:30 Meteo Sunny with some clouds Briefing Objectives are to lower the trench level to the 6x6m grid level, cleanup the site removing loose seagrass and sand. After this a good photomosaic can be made. Work performed Paolo and I went as the first dive team. The sorbona did not work well, as the hose was not flat on the seabed but upwards which is not good as the suction power is limited and the flow of water and sand stops when too much sand is sucked away. After using the sorbona we emptied the iron box again away from the site in the seagrass, using the balloon. The trench level is still about 25cm above the 6x6 grid level. This last dive was very long (70 minutes!) and the final one for men in this project. During the ascent I really enjoyed for minutes looking at the site from above, thinking of the work we had put into it trying to find out what really happened here long ago. In the afternoon photos were taken for a mosaic. All grindstone exposed are labeled now and visible on the photo’s.
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