Science 2

Final Project Honors Earth Science D Period

General Information Name: Mount Rainier Location: Pierce County, Washington Type of Formation: Composite Volcano Approx. Age: 500,000 Years Old Elevation: 14,411 ft.

Chanel Grider May 27th, 2009

Last Eruption: 1894 Volcanic Belt: Cascades

Mount Rainier Washington

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Formation of Mount Rainier Mount Rainier is a composite volcano which means it was formed by multiple eruptions To form a composite volcano, a hot stop must erupt over itself repeatedly, creating multiple layers of lava strata. Mount Rainier 'built up by its own actions, that is, by successive lava flows intermittent with more explosive eruptions that threw out great quantities of pumice and other volcanic ash.” “ The lava, barely fluid, came from a central vent on a rather low base of granite about fifteen miles to the west of the Cascade Range and long after that range was formed.” What is different from most composite volcanoes is that Mr. Rainier is also a small cinder cone built on a crater. “Inside the old crater at a comparatively recent date a small cinder cone has been built up on top of which is a distinct volcanic crater today about half a mile across and funnel-shaped. This is the highest point 14,408 feet above sea level. Most of the old crater rim has been broken down by the action of the ice.” The earliest lava fall in Mt Rainier is from the Lily Formation which dates back to 2.9 million years ago. “The present cone is over 500,000 years old.[12] The volcano is highly eroded, with glaciers on its slopes, and appears to be made mostly of andesite. Rainier likely once stood even higher than today at about 16,000 feet (4,900 m) before a major debris avalanche and the resulting Osceola Mudflow 5,000 years ago.” Sites Used: http://www.nps.gov/mora/ http://en.wikipedia.org/wiki/Mount_Rainier

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Mt. Adams, Washington General Information Name: Mount Adams Location: Yakima. Washington Type of Formation: Composite Volcano Approx. Age: Less Than 275,000 Years Elevation: 8,116 ft Last Eruption: Approx. 550 BC

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Formation of Mount Adams Mount Adams is also a composite volcano. “Composite volcano,[1] is a tall, conical volcano with many layers (strata) of hardened lava, tephra, and volcanic ash. Stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions. The lava that flows from stratovolcanoes tends to be viscous; it cools and hardens before spreading far.” This quick cooling lava causes the layers that are seen.. On Mount Adams, “ice, mostly in the form of glaciers, covers about 6.2 square miles (16.1 km2) of the mountain's upper cone. Water from melting ice and rain slowly percolates through the very porous interior of the main cone and flows out through springs near the base of the volcano.” Mount Adams was probably created by the subduction of the Juan de Fuca plate. Mount Adams was born in late Pleistocene period. The main cone that can currently be seen was probably formed during the last ice age when Mount Adams was captured in it. Adams is notorious for its flat appearance. Adams. Has many false summits. A false summit rises 11,500 feet on the south side of the nearly half-mile wide summit area Sites Used: http://en.wikipedia.org/wiki/Mount_Adams_(Washington)

Devil's Tower

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Wyoming

General Information Name: Devil's Tower Location: Crook County, NE Wyoming Type of Formation: Monolithic Igneous Intrusion (Volcanic Neck) Approx. Age: Oldest Rock is 225 Million Years Old Height: 5112 ft

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Formation of Devils Tower Devils tower is volcanic neck which is the remains of a volcano after the igneous rock erodes away. “Geologists agree that Devils Tower was formed by the intrusion (the forcible entry of molten rock into or between other rock formations) of igneous material.” But the actual process of the creation is still being debated. The most common theory is that devils tower is the remain of an eroded laccolith.. Another theory is that “ Devils Tower is a volcanic plug or that it is the neck of an extinct volcano (an unlikely theory, for there is no evidence of volcanic activity)” The Tower was covered by limestone rock and rain and show had eventually eroded from around the tower. As of today, the tower is currently eroding with occasional chunks falling off. “In any case, geologists agree, the igneous material intruded and then cooled as phonolite porphyry, a light to dark-gray or greenish-gray igneous rock with conspicuous crystals of white feldspar. As the lava cooled, hexagonal (and sometimes 4-, 5-, and 7-sided) columns formed. As the columns continued to cool, vertical cracks developed as the columns shrank horizontally in volume.” Sites: http://www.nps.gov/archive/deto/geology.htm

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Mount Hood, Washington General Information Name: Mount Hood Location: Boarder between Clackamas and Hood River Counties Type of Formation: Composite Volcano Age: Less Than 500,000 Elevation: 11,249 ft Last Eruption: 1790s

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Formation of Mount Hood Mount Hood is also a stratovolcano like Mount Rainier. ”Strato-volcanoes often form impressive, snow-capped peaks which are often exceeding 2500m in height, 1000sq.km in surface, and 400km3 in volume.” Mount Hood is 80% glacier and is home to around 12 major glaciers. Mount Hood continues to grow due to “the growth and collapse of lava domes.” “The volcano has erupted basaltic andesite through dacite in the form of lava flows, domes and pyroclastic eruptions over the last 730,000 years, but ancestral volcanoes in that location can be traced back millions of years.” Mount Hood formed the same way other composite volcanoes did but also has layers of ice and snow due to the 12 glaciers. Most composite volcanoes have a crater at the summit which contains a central vent or a clustered group of vents. Lavas either flow through breaks in the crater wall or issue from fissures on the flanks of the cone. Lava, solidified within the fissures, forms dikes that act as ribs which greatly strengthen the cone. Sites: http://scienceblogs.com/eruptions/2009/04/volcano_profile_mt_hood.php http://pubs.usgs.gov/gip/volc/types.html http://vulcan.wr.usgs.gov/Volcanoes/Hood/description_hood.html

Craters of the Moon 9

Idaho

Formation of Craters of the Moon

The Craters of the Moon are a lava field located in Idaho. A lava field is a plain full of flat lying basalt lava. A lava field is simply created when a volcano erupts and the lava seeping through the General Information cone or the vents seep down into a low lying plane and harden. "The COM lava field is the largest dominantly Holocene basaltic lava field in the lower 48 states (Kuntz, et al, 1992); it covers 618 mi2 2 Name: Craters of the km Moon (1,600 ). COM lava field is a composite field made up of at least 60 lava flows and 25 tephra cones." The Craters of the Moon seem to have weird chemical reactions and release odd chemicals. Location: Snake"The River Plain, Idaho basalt deposits in the COM lava field exhibit a wide range of chemical compositions. Though the COM lava flows are believed to have similar parent magma to the volcanoes in the rest of the Plain, theirFlood varied Basalt compositions are due to crustal contamination from assimilating older rocks or from Type of Formation: crystal fractionation" In the COM, there are many theories on why it is shaped as it is. One theory is that "the basalt-sediment sequence is underlain by rhyolitic lava flows, ignimbrites (rock formed by Age: 15,000 years the widespread deposition and consolidation of ash flows), and pyroclastic deposits (formed by volcanic explosion or aerial expulsion from a volcanic vent)." Also it is believed that volcanism is the Size: 2,892 squared km cause of the east propagating rift.

C olu mbi a and

Site: http://www.nps.gov/archive/crmo/geology/geology-1.htm

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Snake River Plateaus

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Formation of Columbia and Snake River Plateau Plateaus are formed as a result of geologic uplift, or the slow upward movement of large parts of stable areas of Earth's crust or formed by plates in the lithosphere colliding. The Columbia and Snake River Plateau were formed "as a result of many lava flows that spread out over hundreds of thousands of square miles, building up the land surface. These latter plateaus are known as lava or basalt plateaus." Originally these plateaus were covered but are now exposed due to the Missoula Floods.

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Mt. St. Helens Washington

General Information Name: Mount Saint Helens Location: Skamania County, Washington Type of Formation: Active Composite Volcano Age: Greater than 40,000 years Elevation: 8,365 ft Volcanic Arc: Cascades Last Eruption: July 10, 2008

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The Formation of Mount St. Helens Mount St. Helens is a composite volcano notorious for its deadly eruption in 1980. As a composite volcano, Mount St. Helens was formed by burst of lava layering over themselves creating the walls of the volcanic cone. Another factor in the creation of Mount St. Helens is the Juan de Fuca plate pushing into the North American plate. During the winter of 1980-1981 a new glacier appeared on the mountain. Because of the new volcanic activity in 2004, "the glacier lobes were pushed aside and upward by the growth of new volcanic domes" creating a new structure on the volcano. The diagram on the page before continues this explanation.

Crater Lake Washington 14

General Information Name: Crater Lake Location: Oregon Type of Formation: Caldera Lake Age: Around Since 7,700 BC Depth: 1148 ft Width: 5 miles

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Formation of Crater Lake Crater Lake is a caldera lake formed which is a volcanic crater. Crater Lake was formed after the Mount Mazama collapsed into itself creating a depression in the ground. The pictures below are drawings that show the collapsing of Mt. Mazama and how it lead to the creation of Crater Lake. The current area is currently still active as underground and underwater volcanic activities created Wizard Island.

La Sal Mountains, Utah General Information Name: La Sal Mountains Location: Grand County and San Juan Counties, Utah

Formation of the La Sal Mountain Range

Mountain Range: Rocky

"The range formed as a result of intrusion of igneous rocks and subsequent erosion of the surrounding less-resistant sedimentary rocks. The most abundant igneous rocks are Mountain Range porphyritic, with phenocrysts of hornblende and plagioclase: these rocks are called diorite in some accounts but trachyte in at least one other source. Syenite, some containing the unusual mineral nosean, makes up a few percent of the Range: igneous rocks Elevation 12,721 ft – present. Some of the igneous intrusions have the shapes of laccoliths. Ages of these igneous rocks fall in the interval 25 to 28 million years. The magmas were emplaced 12,001 ft into sedimentary rocks with ages from Permian to Cretaceous."

Highest Point: Mount Peale 16

Sites: http://en.wikipedia.org/wiki/La_Sal_Mountains

Shiprock,

New Mexico

General Information Name: Shiprock Location: Shiprock, New Mexico Type of Formation: Breccia and Igneous Rock Elevation: 7,177 ft Age of Rock: 27 Million Years

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Formation of Shiprock "Shiprock Peak is the "neck", or remains of a solidified lava core, of a dormant 40 million year old volcanic pinnacle. It is shaped somewhat like a 19th century Clipper Ship with high trap-dykes running north from Utah and south from the main spire and rising about 1,800 feet above the four-corners New Mexican plain. It's elevation is 7,178 feet above sea level. It lies about 13 miles southwest of the town of Shiprock, New Mexico, and 6 miles west of Highway 66. It is also visible from." "The remnant of an eruption around 30 million years ago during the Oligocene, it is the basalt core of an extinct volcano. Near the main peak, one can see small pinnacles, the remains of smaller auxiliary volcanic vents." Shiprock was formed by volcano eroding around the volcanic neck. Sites: http://www.lapahie.com/Shiprock_Peak.cfm http://www.emporia.edu/earthsci/student/kuss1/shiprock.html

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General Information Name: Palisades Location: NE New Jersey and Southern New York Age: Triassic Period Height: 350-550 ft Length: 20 miles

Palisades, New Jersey

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Formation of Palisades The Palisades are a series of cliffs left over from when the North American plate was attached to the African plate. " The Palisades sill is an igneous intrusion that formed approximately 200 million years ago in the Jurassic period. This 1000 foot thick intrusion “injected” itself between layers of sedimentary rock of the Lockatong formation as the supercontinent of Pangaea began to split apart (or "rift"), forming the North American plate and the African plate. The Palisades formed when rising magma (molten rock) from the earth’s mantle pushed and stretched the overlying crust. As the magma rose, the crust thinned and begun to crack and pull apart from the tensional stress." Faults formed when crust thinned and cracked apart and magma would travel through the crust, creating a new ocean lithosphere. With the Palisades being formed by the process that creates the oceans crust, it is technically supposed to be underwater. "The reason is that the Palisades sill is at a failed rifting spot. While the continents were pulling apart at the Palisades and Watchung, something happened to cause the rifting to end at those locations and to begin at another location. The final rifting took place approximately 100 miles to the east of where the Palisades are today. As you would expect, the actual rift zone is now under water. The rifting is taking place at the midocean ridge in the middle of the Atlantic Ocean." Sites: http://www.geocaching.com/seek/cache_details.aspx?wp=gczcha

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Sideling Hill, Maryland

General Information

Name: Sideling Hill Location: West Virginia, Pennsylvania, and Maryland Type of Formation: Syncline Rock Exposure Elevation: 2,301 ft

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Formation of Sideling Hill Sideling Hill is a syncline mountain. A syncline is a downward dip or fold in underground strata. A syncline is a fold in which the youngest rocks are in the core of a fold. In Sideling Hill there are around 810 ft of strata layers. " The Rockwell and Purslane Formations were deposited during the early Mississippian, about 330 to 345 million years ago. At the road cut, approximately 450 feet of the Rockwell Formation are exposed and consist of interbedded, tan and gray-green, clay rich sandstones, gray-green to dark-gray, silty shales, and gray to dark-gray, sandy siltstones with several intervals of red-brown claystone near the top. In places, thin shaly coals and coaly shales are interbedded with shales and siltstones. These coals are interesting in that coal is typically not common in Lower Mississippian strata. An even rarer and indeed unusual lithology, termed diamictite, is present approximately 70 feet above the base of the section (A of Figure 2). A diamictite is a very poorly sorted to unsorted rock composed of clay, silt, sand, and pebbles or cobbles." Sites: http://www.mgs.md.gov/esic/brochures/sideling.html

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Grand Teton Mountains, Wyoming

Formation of Grand Teton General Information " 3,000 million years ago in Precambrian time, sand, limey ooze, silt and clay were deposited in a marine trough (accurate dating is not possible, due to subsequent partial recrystallization of the resulting rock). Interbeded between these layers were volcanic deposits, probably from an island Name:limestones, Teton Range arc. These sediments were later lithified into sandstones, and various shales. These rocks were 5 to 10 miles (8 to 16 km) below the surface when orogenies (mountain-building Location: Wyoming Side of them, episodes) around 2,800 to 2,700 million years ago intensely folded and metamorphosed creating alternating light and dark banded gneiss and schist. Today these rocks dominate the Teton Range with good examples easily viewable in Death Canyon and other canyons in the Teton Wyoming/Idaho border Range. The green to black serpentine created was used by Native Americans to make bowls." Siters:

Elevation: 13,770 ft http://en.wikipedia.org/wiki/Geology_of_the_Grand_Teton_area

Type of Formation: Mountain Range: Rocky Mountain Range Age: N/A

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General Information

Black Hill, South Dakota Name: Black Hills

Location: Western South Dakota Type of Formation: Volcanic, Rock, and Tertiary Mountain Building Highest Point: 7,242 ft Age: Around since 7000 BC

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Formation of the Black Hills "A Tertiary mountain-building episode is responsible for the uplift and current topography of the Black Hills region. This uplift was marked by volcanic activity in the northern Black Hills. The southern Black Hills are characterized by Precambrian granite, pegmatite, and metamorphic rocks that comprise the core of the entire Black Hills uplift. This core is rimmed by Paleozoic, Mesozoic, and Cenozoic sedimentary rocks. The stratigraphy of the Black Hills is laid out very much like a target as it is an oval dome, with rings of different rock types dipping away from the center." "The granite of the Black Hills was emplaced by magma generated during the Trans-Hudson orogeny and contains abundant pegmatite. The core of the Black Hills has been dated to 1.8 billion years." "The final layers of the Black Hills consist of sedimentary rocks. The oldest of which lies on top of the metamorphic layers at a much shallower angle. This rock called the Deadwood Formation is mostly sandstone and was the original source of gold found in the Deadwood area. "" The next rock layer, the Spearfish Formation forms a valley around the hills called the red valley. It is mostly red shale with beds of gypsum." "The preceding layers were deposited in a horizontal manner. All of them can be seen in core samples and well logs from the flattest parts of the Great Plains. It took a period of uplift to bring them to their present topographical levels in the Black Hills. This uplift called the Laramide orogeny began around the beginning of the Cenozoic and left a line of igneous rocks through the northern hills superimposed on the rocks already discussed. " Sites: http://en.wikipedia.org/wiki/Black_Hills#Precambrian

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Adirondack Mountains, New York

General Information Name: Adirondack Mountains Location: Clinton, Essex, Fra`nklin, Fulton, Hamilton, Herkimer, Lewis, Saint Lawrence, Saratoga, Warren, and Washington counties in New York. Type of Formation: Mountain Range

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Formation of the Adirondack Mountains "The mountains consist primarily of metamorphic rocks, mainly gneiss, surrounding a central core of intrusive igneous rocks, most notably anorthosite, in the high peaks region. These crystalline rocks are a lobe of the Precambrian Grenville Basement rock complex and represent the southernmost extent of the Canadian Shield," " The region was once covered, with the exception of the higher summits, by the Laurentian Glacier, whose erosion, while perhaps having little effect on the larger features of the country, has greatly modified it in detail, producing lakes and ponds, whose number is said to exceed 1300, and causing many falls and rapids in the streams."" The Adirondack Mountains make up a circular region that is part of the Grenville Province, a large belt of basement rock. The region is divided into the Central Highlands and the Northwest Lowlands, which are separated by the Carthage-Colton Mylonite Zone. It was once covered by the same layers of sedimentary rock that now surround it, but recent uplift and erosion have exposed the basement. Seen from space, the region has several prominent features: long, straight valleys; gently curved ridges and valleys; and a radial drainage pattern. The rocks of the Adirondacks, almost without exception, are metamorphic. They have been subjected to high temperatures and pressures at depths of up to 30 km in the earth's crust. Most of the rocks in the Northwest Lowlands are metasedimentary or metavolcanic and have a complex history. Most of the rocks in the Central Highlands are metaplutonic; granitic gneiss is the most common. Metanorthosite forms several large bodies in the Central Highlands; the largest makes up the High Peaks area. Olivine metagabbro bodies are scattered throughout the eastern and southeastern Adirondacks. " Sites: http://en.wikipedia.org/wiki/Adirondack_Mountains http://gretchen.geo.rpi.edu/roecker/nys/adir_txt.html

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Basin and Range, Nevada

General Information

Name: Basin and Range Location: Southwestern U.S and Northwestern Mexico Type of Formation: Geological Province Age:20 million years

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Formation of Basin and Range The topography of the Basin and Range is a result of crustal extension within this part of the North American Plate. An Extenstion is when the earth crust is being pulled apart . "The Basin and Range Province is characterized by extension, ranging from a total of 50% or less to 200% extension of the pre-Basin and Range land area (Faulds and Varga, 1998). This extension occurs mostly along large normal faults and fault zones where these normal faults interact with each other. " " Basin and Range extension began during the Miocene Epoch (~17 Ma) near the Northern Nevada Rift in the center of the province and has continued through present, propogating westward toward the Sierra Nevada and eastward into southeastern Idaho and westernmost Wyoming. Extension is a result of the cessation of the compression during the Cordilleran Orogeny. During the Cordilleran Orogeny, there was great crustal thickening, and the Basin and Range counteracts that thickening by crustal thinning through extension. The Basin and Range Province in Idaho is cross-cut by the volcanic track of the Snake River Plain. The map below shows the extent of the Basin and Range Province in southeastern Idaho. " Sites: http://en.wikipedia.org/wiki/Basin_and_Range_Province http://geology.isu.edu/Digital_Geology_Idaho/Module9/mod9.htm

Sugarloaf Mountain, Maryland General Information

Name: Sugarloaf Mountain Location: Frederick County, Maryland Type of Formation: Isolated Rock Hill Elevation: 1,282 ft Age: Approx. 500 million years

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Formation of Sugarloaf Mountain " Sugarloaf is known as a monadnock, a mountain that remains after the erosion of the surrounding land. Here, that process took approximately 14 million years. The rugged cliffs on the summit are composed primarily of quartzite, the predominant type of rock on the mountain." For monadnocks, Volcanic or other processes may give a body of rock a resistance to eroding, inside a body of softer rock such as limestone which is more susceptible to erosion. When the less resistant rock is eroded away to form a plain, the more resistant rock is left behind as an isolated mountain. The strength of the uneroded rock is often attributed to the tightness of its jointing. "If the monadnock is dome-shaped and formed from granite-gneiss, it can also be called a bornhardt." Sugarloaf mountain is either an outlier to the east of the main mass of Catoctin Mountain, or a root remnant of the ancient Appalachian land mass. Sites: http://en.wikipedia.org/wiki/Sugarloaf_Mountain_(Maryland) http://www.sugarloafmd.com/sl_facts.html

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Colorado Plateau

General Information Name: Colorado Plateau Location: Colorado Type of Formation: Plateau Age:Really Old (Rock dates back to first Ice Age) Height: 8000 ft (highest point) Area:337,000 km²

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Formation of the Colorado Plateau " The Precambrian and Paleozoic history of the Colorado Plateau is best revealed near its southern end where the Grand Canyon has exposed rocks with ages that span almost 2 billion years. The oldest rocks at river level are igneous and metamorphic and have been lumped together as "Vishnu Basement Rocks;" the oldest ages recorded by these rocks fall in the range 1950 to 1680 million years. Throughout the Paleozoic Era, tropical seas periodically inundated the Colorado Plateau region. " " In late Paleozoic and much of the Mesozoic era the region was affected by a series of orogenies (mountain-building events) that deformed western North America and caused a great deal of uplift. Eruptions from volcanic mountain ranges to the west buried vast regions beneath ashy debris. " " The area was again covered by a warm shallow sea when the Cretaceous Seaway opened in late Mesozoic time. The Dakota Sandstone and the Tropic Shale were deposited in the warm shallow waters of this advancing and retreating seaway. Several other formations were also created but were mostly eroded following two major periods of uplift. " " Minor uplift events continued through the start of the Cenozoic era and were accompanied by some basaltic lava eruptions and mild deformation. "

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Olympic Mountains, Washington

General Information

Name: Olympic Mountains Location: Olympic Peninsula, Washington Type of Formation: Mountain Range Highest Point: Mount Olympus :7,962 ft Age: 35 million years 34

Formation of Olympic Mountains A majority of the formation of the Olympic mountains is due to the Juan De Fuca plate diving under the North American plate ."The oceanic plate, being more dense, dives under the North American continental-crust plate in a subduction zone and trench that started about 34 million years ago at this location. As the oceanic crust slab slants down deeper under the continent, the process produces basalt flows, Cascade volcanoes, granite batholiths, and major earthquakes. The ‘core rocks’ of the Olympic Mountains are mostly sediments from the subducting oceanic crustal slab, scraped off and ‘underplated’ on the bottom of the continental crust. This stacking of successive scrapes thus continually thickens and raises the older, top surface. Arching of the subducting plate under the Olympics adds to the uplift, while erosion eats away the oldest, top sediments. The top surface at Mount Olympus was underplated by subduction off the oceanic slab about 17 million years ago." Sites: http://www.dungenessrivercenter.org/Geology.html

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Half Dome Mountain in Yosemite National Park

General Information

Name: Half Dome Mountain Location: Yosemite National Park, California Type of Formation: Granite Dome Mountain Age: 93 million years Height: 4,737 ft 36

Formation of the Half Dome Mountain The Half Dome "was probably never a full dome like North Dome, which it faces, geologists believe that about 20% of the original rock was sheared off by glaciers. The face looks smooth and slippery but is actually filled with ledges and ridges…"" The flat face overlooks Yosemite Valley, whose U-shaped cross section is attributed to glacial action. The dome itself reflects the general shape of an intrusion of granodiorite deep underground. As the intrusion became exposed by erosion, the change in pressure caused the rock to crack apart in thin shells, which fall off the sides and leave the mountain clean. The process is called exfoliation, and Half Dome is a classic exfoliation dome. " Sites: http://geology.about.com/library/bl/peaks/blhalfdome.htm http://www.frommers.com/destinations/yosemitenationalpark/1088026075.html

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Bryce National Park

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Formation of Bryce National Park " Bryce Canyon was once covered by sea, mountains, desert and coastal plain. Over millions of years, the rock and land was subject to violent storms and severe changes. Earthquakes, mudslides and volcanoes roared upon the primitive earth, forcing, molding and reshaping it. Seas and streams came and went, moving sediment and depositing it in layers."" Bryce Canyon it freezes at night approximately 360 days of the year. The freeze and thaw cycle loosens the slope surface, allowing debris to be sluffed off by water run-off." " Bryce Canyon was not formed from erosion initiated from a central stream, meaning it technically is not a canyon. Instead headward erosion has excavated large amphitheater-shaped features in the Cenozoic-aged rocks of the Paunsagunt Plateau.[5] This erosion exposed delicate and colorful pinnacles called hoodoos that are up to 200 feet (61 m) high." Sites: http://www.zionnational-park.com/bgeology.htm http://en.wikipedia.org/wiki/Bryce_Canyon_National_Park

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Colorado River in Canyon lands National

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Formation of the Colorado River The most powerful force to have an impact on the Grand Canyon is erosion, primarily by water (and ice) and second by wind. Other forces that contributed to the Canyon's formation are the course of the Colorado River itself, vulcanism, continental drift and slight variations in the earths orbit which in turn causes variations in seasons and climate. After erosion by liquid water the next most powerful force is probably its solid form, ice. In the colder months, especially on the north rim, water seeps into cracks between the rocks. These cracks can be caused by seismic activity, or by the constant soaking and drying of the rocks. When the water freezes it expands and pushes the rocks apart and widens the cracks. Eventually rocks near the rim are pushed off the edge and fall into the side canyons. These rocks sometimes hit other rocks and are stopped but on occasion one fall by a large rock will cause a cascading effect and create a rock fall that will alter the landscape drastically in the side canyon." Sites: http://www.bobspixels.com/kaibab.org/geology/gc_geol.htm

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Great Falls-Potomac River, MarylandVirginia

Formation of Great Falls There are several factors to the formation of Great Falls."First of these was the middle Proterozoic Grenville Orogeny, from 1,200 to 1,000 Ma, which resulted from the creation of the supercontinent Rodinia. Some metamorphic rocks from this orogeny, including the Baltimore Gneiss in the Piedmont Province, are visible, but most of the involved rocks form the basement for the north-central Appalachian mountains The next major event was the opening of the Iapetus Ocean in the late Proterozoic and early Cambrian. During the middle and late Paleozoic, from the Ordovician to the Permian, the Iapetus Ocean closed in a series of four orogenies: the Penobscottian Orogeny, the Taconic Orogeny, the Acadian Orogeny and the Alleghenian Orogeny. The late Devonian Acadian Orogeny, about 370 Ma, resulted when the continent of Avalon collided with Euramerica. This collision has left few traces in the mid-Atlantic region. The final orogeny, the Alleghenian Orogeny, at 400 to 350 Ma, resulted from the formation of Pangea in the late Carboniferous and early Permian. This orogeny built the Appalachian Mountains and produced significant faulting and folding in the mid-Atlantic states and New England. Further faulting occurred during the opening of the Atlantic Ocean and breakup of Pangea in the middle Triassic and resulted in the formation of basins in the Piedmont region." Sites: http://www.gps.caltech.edu/~rkopp/collegepapers/potomac/potomac.html

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Delta, Mississippi River, Louisiana

Formation of Mississippi River Delta The giant bird's foot delta, featuring a large middle toe, that terminates the lower Mississippi River in southern Louisiana marks the seaward growth of land into the Gulf of Mexico. The Mississippi-Missouri River system collects eroded debris from the central U.S. Upon reaching the Gulf, the river's velocity slows, abruptly reducing its capacity to carry suspended mud and sand, and the sediment is deposited in vast alluvial fans not visible on the map." " Build-up of the Gulf of Mexico shoreline due to the outflow of the Mississippi River has been occurring in a periodic fashion since the late Jurassic period. This same process is responsible for build up of the larger Mississippi embayment; however, the delta region is the most recent and ecologically distinct portion. The latest cycle of delta movement can be traced to the pleistocene epoch, when a large amount of ocean water was tied up in glaciers." Sites: http://en.wikipedia.org/wiki/Mississippi_River_Delta http://www.nationalatlas.gov/articles/geology/features/delta.html

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Yellowstone River, a V-shaped River valley

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Formation of V-Shaped River Valley A v shaped river valley is basically a river in its youth. " River valley with a V-shaped cross-section. Such valleys are usually found near the source of a river, where the steeper gradient means that there is a great deal of corrasion (grinding away by rock particles) along the stream bed, and erosion cuts downwards more than it does sideways. However, a V-shaped valley may also be formed in the lower course of a river when its powers of downward erosion become renewed by a fall in sea level, a rise in land level, or the capture of another river. The angle of the V-shaped cross-section depends on the rate of uplift of rock, the type of rock, the erosive ability of the river, the type of climate, and the stage of the river. " The younger a river is the more V shaped it will be.

Sites: http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0035488.html

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Mammoth Cave National Park, Kentucky

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Formation of Mammoth Cave "How the Caves Formed 350 Million Years Ago: The region we now call south-central Kentucky was 10 degrees south of the equator and submerged beneath a warm and shallow sea. For 70 million years, sediments—including calcium carbonate shells from sea creatures—accumulated on the ocean floor ultimately depositing 1,200 to 1,400 feet of limestone. 300 Million Years Ago: A river, flowing into the ocean from the north, deposited 50 to 100 feet of sand and silt, creating a layer of sandstone and shale over the existing limestone. 280 Million Years Ago: The sea level began to drop and the continent began to rise, exposing the layers of limestone and sandstone. Forces within the earth caused the surface to buckle and twist, causing tiny cracks between and across the layers of limestone and sandstone. At the same time, river systems as we know them developed on the surface. 3 Million Years Ago: Forces of erosion had left a sandstone-capped ridge (insoluble to water) above the Green River. Beyond this ridge to the south there is a limestone plain called, "Pennyroyal Plateau," filled with sinkholes. When it rained, water seeped through the sinkholes into the tiny cracks and crevices within the limestone. Combining with carbon dioxide (and thus becoming a weak acid), the water slowly made its way through the limestone toward the Green River. Ultimately, on its journey toward the river, the water traveled under the sandstone-capped ridge by dissolving away larger and larger passages from its limestone bed, in the process forming an intricate and interconnected river system. The Last Million Years: As the Green River continued to cut deeper into its bed, the water table continued to drop. To keep up, new underground drains formed in the limestone bed, creating new channels beneath the original ones. Water drained from the higher passages, leaving behind air-filled passageways that visitors recognize—cave. Thus, the oldest cave passages are the closest to the surface and the youngest horizontal passages are the deepest underground. Now: At the present water table, cave passages continue to form in the deepest depths of Mammoth Cave." Sites: http://www.ohranger.com/mammoth-cave/geology

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Old Faithful Geyser, Yellowstone, Wyoming

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Formation of Old Faithful "The formation of geysers is due to particular hydrogeological conditions, which exist in only a few places on Earth, and so they are a fairly rare phenomenon. Generally all geyser field sites are located near active volcanic areas, and the geyser effect is due to the proximity of magma. Generally, surface water works its way down to an average depth of around 2,000 metres (6,600 ft) where it meets up with hot rocks. The resultant boiling of the pressurized water results in the geyser effect of hot water and steam spraying out of the geyser's surface vent." Site: http://en.wikipedia.org/wiki/Geyser

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Sinkhole

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Formation of Sink Holes " Snkholes are a common feature of Florida's landscape. They are only one of many kinds of karst landforms, which include caves, disappearing streams, springs, and underground drainage systems, all of which occur in Florida. Karst is a generic term which refers to the characteristic terrain produced by erosional processes associated with the chemical weathering and dissolution of limestone or dolomite, the two most common carbonate rocks in Florida. Dissolution of carbonate rocks begins when they are exposed to acidic water. Most rainwater is slightly acidic and usually becomes more acidic as it moves through decaying plant debris. Limestones in Florida are porous, allowing the acidic water to percolate through their strata, dissolving some limestone and carrying it away in solution. Over eons of time, this persistent erosional process has created extensive underground voids and drainage systems in much of the carbonate rocks throughout the state. Collapse of overlying sediments into the underground cavities produces sinkholes. When groundwater discharges from an underground drainage system, it is a spring, such as Wakulla Springs, Silver Springs, or Rainbow Springs. Sinkholes can occur in the beds of streams, sometimes taking all of the stream's flow, creating a disappearing stream. Dry caves are parts of karst drainage systems that are above the water table, such as Marianna Caverns."

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Yosemite Falls

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Formation of Yosemite Falls

"A waterfall is usually a body of water resulting from water, often in the form of a stream, flowing over an erosion-resistant rock formation that forms a nickpoint, or sudden break in elevation.Some waterfalls form in mountain environments in which the erosive water force is high and stream courses may be subject to sudden and catastrophic change. In such cases, the waterfall may not be the end product of many years of water action over a region, but rather the result of relatively sudden geological processes such as landslides, faults or volcanic action. In cold places, snow will build up in winter and melt and turn into a waterfall in summer. Typically, a river flows over a large step in the rocks that may have been formed by a fault line. As it increases its velocity at the edge of the waterfall, it plucks material from the riverbed. This causes the waterfall to carve deeper into the bed and to recede upstream. Often over time, the waterfall will recede back to form a canyon or gorge downstream as it recedes upstream, and it will carve deeper into the ridge above it."

Site: http://en.wikipedia.org/wiki/Waterfall

Sierra Nevada Mountains, California

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Formation of the Sierra Nevadas Physiographically, it is a section of the Cascade-Sierra Mountains province, which in turn is part of the larger Pacific Mountain System physiographic division. In west-east cross section, the Sierra is shaped like a trapdoor: the elevation gradually increases on the west slope, while the east slope forms a steep escarpment.[1] Thus, the crest runs principally along the eastern edge of the Sierra Nevada range. Rivers flowing west from the Sierra Crest eventually drain into the Pacific Ocean, while rivers draining east flow into the Great Basin and do not reach any ocean by natural means.[2] [However, water from several streams and the Owens River is redirected to the city of Los Angeles (see Los Angeles Aqueduct). Thus, by artificial means, some east-flowing river water now does ultimately make it to the Pacific Ocean.] The wellknown granite that makes up most of the southern Sierra started to form in the Triassic period. At that time, an island arc collided with the West coast of North America and raised a set of mountains, in an event called the Nevadan orogeny. Twenty million years ago, crustal extension associated with the Basin and Range Province caused extensive volcanism in the Sierra About 4 million years ago, the Sierra Nevada started to form and tilt to the west. Rivers started cutting deep canyons on both sides of the range. The Earth's climate cooled, and ice ages started about 2.5 million years ago. 55 Sites:

http://en.wikipedia.org/wiki/Sierra_Nevada_(U.S.)

Esker

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Formation of an Esker "The low ridge winding across the landscape of northern Manitoba, Canada, is a classic esker. When a great ice sheet covered central North America, about 10,000 years ago, a stream of meltwater ran beneath it at this location. The abundant sand and gravel, freshmade under the glacier's belly, piled up on the streambed while the stream melted its way upward. The result was an esker: a ridge of sediment in the form of a rivercourse. Normally this kind of landform would be wiped out as the ice sheet shifts and the meltwater streams change course. This particular esker must have been laid down just before the ice sheet stopped moving and began to melt for the last time. Similarly, the small lakes to the right in this photo mark where the last masses of ice sat while meltwater laid sediment down all around them"

Sites http://geology.about.com/library/bl/images/blesker.htm

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U Shaped Glacial Valley

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Formation of a U – Shaped Glacial Valley " When allowed to spread out, a glacier erodes the landscape uniformly, but when confined within valley walls it tends to deepen and widen the valley floor. The commonly V-shaped stream valley is converted to a U-shaped valley because the U-shape provides the least frictional resistance to the moving glacier. Because a glacier has a much greater viscosity and cross section than a river, its course has fewer and broader bends, and thus, the valley becomes straighter and smoother. The valley walls may be almost vertical and may be striated by boulders dragged by the glacier, and the valley floor may be covered with till or moraines. Because thickness of the ice is the dominant factor in the deepening process, smaller tributary glaciers erode their troughs less rapidly than the main glacier does. When the glaciers melt, the tributary troughs are left as hanging valleys high on the walls of the main glacial valley. Postglacial streams may form waterfalls from the mouths of the hanging valleys, a well-known example being Yosemite Falls, California."

Site: http://www.britannica.com/EBchecked/topic/234551/glacial-valley

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Arches Natural Park

Formation of the Arches National Park " Salt under pressure is unstable, and the salt bed below Arches began to flow under the weight of the overlying sandstone. This movement caused the overlying rock to buckle and shift, thrusting some sections upward into domes, dropping others into surrounding cavities, and causing vertical cracks which would later contribute to the development of arches. As the subsurface movement of salt shaped the surface, erosion stripped away the younger rock layers. Water seeped into cracks and joints, washing away loose debris and eroding the "cement" that held the sandstone together, leaving a series of free-standing fins. During colder periods, ice formed, its expansion putting pressure on the rock, breaking off bits and pieces, and sometimes creating openings. Many damaged fins collapsed. Others, with the right degree of hardness and balance, have survived as the world famous formations of Arches National Park. Faults deep in the Earth also contributed to the instability on the surface. The result of one such 2,500-foot displacement is called the Moab Fault and is visible from the Arches Visitor Center. Salt Valley was also formed by such a displacement. Except for isolated remnants, the major rock formations visible in the park today are the salmon-colored Entrada Sandstone, in which most of the arches form, and the tan-colored Navajo Sandstone. "

Site:

60 http://gorp.away.com/gorp/resource/us_national_park/ut/geo_arch.htm

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