Sharktooth Hill Subduction Key
... 7. Which animal fossil is NOT found in the Sharktooth Hill (or Bakersfield) area? a. Dinosaur bones b. Shark teeth c. Sea lion bones d. Sea shells 8. Why are there no shark bones found in the bone bed? a. Sharks have no bones, only teeth remain b. There were no sharks c. The shark bones dissolved d ...
... 7. Which animal fossil is NOT found in the Sharktooth Hill (or Bakersfield) area? a. Dinosaur bones b. Shark teeth c. Sea lion bones d. Sea shells 8. Why are there no shark bones found in the bone bed? a. Sharks have no bones, only teeth remain b. There were no sharks c. The shark bones dissolved d ...
Slide 1
... Paleozoic con’t • Extensive erosion, transportation (rivers), deposition of sediments from the Shield into adjacent seas • Compression of sediments in ancient seas create sedimentary rock • Today these sedimentary rocks form the bedrock for parts of every province • Organisms in seas form basis of ...
... Paleozoic con’t • Extensive erosion, transportation (rivers), deposition of sediments from the Shield into adjacent seas • Compression of sediments in ancient seas create sedimentary rock • Today these sedimentary rocks form the bedrock for parts of every province • Organisms in seas form basis of ...
Geology of the Santa Cruz Mountains
... lava flows out over a distance of several square miles. The quarry on Old Page Mill Road exposes this lava flow of Miocene basalt, a dark rock overlain by light colored sandstone. During the close of the Miocene, about 12 million years ago, folding and faulting upheaved the most recent precursor of ...
... lava flows out over a distance of several square miles. The quarry on Old Page Mill Road exposes this lava flow of Miocene basalt, a dark rock overlain by light colored sandstone. During the close of the Miocene, about 12 million years ago, folding and faulting upheaved the most recent precursor of ...
Stream transport
... Widening of the Atlantic has taken about 200 million years. In the meantime, the Appalachians -- originally about 30,000 feet tall -- have been eroding… ...
... Widening of the Atlantic has taken about 200 million years. In the meantime, the Appalachians -- originally about 30,000 feet tall -- have been eroding… ...
California is mostly made up of Mesozoic and Cenozoic materials
... where sediments are exposed along the Bakersfield Arch. The bed includes marine vertebrate fossils such as sharks, sea lions, turtles, whales, and other large life forms. The Bone Bed covers 47 square miles and is only about a foot thick. This bed is the most fossil-rich Middle Miocene bone bed in t ...
... where sediments are exposed along the Bakersfield Arch. The bed includes marine vertebrate fossils such as sharks, sea lions, turtles, whales, and other large life forms. The Bone Bed covers 47 square miles and is only about a foot thick. This bed is the most fossil-rich Middle Miocene bone bed in t ...
Desert processes and Death Valley
... There are no large canyons in Death Valley, but not far away is the largest of them all – the Grand Canyon. This is a deep and wide valley cut by the Colorado River, which flows all the year, supplied by water from the high mountains of Colorado. Because deserts have very shallow (if any) soil, the ...
... There are no large canyons in Death Valley, but not far away is the largest of them all – the Grand Canyon. This is a deep and wide valley cut by the Colorado River, which flows all the year, supplied by water from the high mountains of Colorado. Because deserts have very shallow (if any) soil, the ...
NorthShoreGeol - Salem State University
... part of a series of worldwide collisions that culminated in the formation of Pangea during the Permian Period. Pangea remained intact for approximately 100 million years when it started to rift apart. During and following their formation the Appalachian Mountains were subject to tectonic and erosion ...
... part of a series of worldwide collisions that culminated in the formation of Pangea during the Permian Period. Pangea remained intact for approximately 100 million years when it started to rift apart. During and following their formation the Appalachian Mountains were subject to tectonic and erosion ...
Sea Level Change Concept Maps
... Geologic forces that form and shape mountains are both constructive and destructive. ...
... Geologic forces that form and shape mountains are both constructive and destructive. ...
Fields of Science
... Joints are breaks in bedrock along which no movement has occurred. They can provide channels for fluids. Groundwater that flow through them and dissolves limestone can cause cavern formation. ...
... Joints are breaks in bedrock along which no movement has occurred. They can provide channels for fluids. Groundwater that flow through them and dissolves limestone can cause cavern formation. ...
Faults - Geology
... are fractures in the earth’s crust where movement has occurred. There are three types: normal, reverse or thrust, and strike-slip (also called transcurrent). ...
... are fractures in the earth’s crust where movement has occurred. There are three types: normal, reverse or thrust, and strike-slip (also called transcurrent). ...
App4 GeolHistory
... Brief Geologic History of the Flathead Subbasin The Precambrian rocks of the Belt Supergroup that underlie the Flathead Subbasin formed from sediments deposited in and near a large but shallow sea or inland lake during the middle Proterozoic (from roughly 1,600 to 800 million years ago). This large ...
... Brief Geologic History of the Flathead Subbasin The Precambrian rocks of the Belt Supergroup that underlie the Flathead Subbasin formed from sediments deposited in and near a large but shallow sea or inland lake during the middle Proterozoic (from roughly 1,600 to 800 million years ago). This large ...
1 billion years ago
... Brownstones of Connecticut are made from sediments that were deposited in the rift valley. The flood basalt lavas that erupted along the rifts are now preserved as traprock ridges. One lava flow was about 200 meters (over 600 feet) thick! Dinosaurs roamed the Connecticut valley and left footprints a ...
... Brownstones of Connecticut are made from sediments that were deposited in the rift valley. The flood basalt lavas that erupted along the rifts are now preserved as traprock ridges. One lava flow was about 200 meters (over 600 feet) thick! Dinosaurs roamed the Connecticut valley and left footprints a ...
Death Valley through time
... wholesale invasion of well-aerated shallow surface waters and tidal flats. In view of the thin air of the time, hard shells may then have been a shallow-water protection against ultraviolet radiation. Or were they simply a response to predation, this planet’s first evidence of aggression? In Death ...
... wholesale invasion of well-aerated shallow surface waters and tidal flats. In view of the thin air of the time, hard shells may then have been a shallow-water protection against ultraviolet radiation. Or were they simply a response to predation, this planet’s first evidence of aggression? In Death ...
Geology of the Death Valley area
The exposed geology of the Death Valley area presents a diverse and complex set of at least 23 formations of sedimentary units, two major gaps in the geologic record called unconformities, and at least one distinct set of related formations geologists call a group. The oldest rocks in the area that now includes Death Valley National Park are extensively metamorphosed by intense heat and pressure and are at least 1700 million years old. These rocks were intruded by a mass of granite 1400 Ma (million years ago) and later uplifted and exposed to nearly 500 million years of erosion.Marine deposition occurred 1200 to 800 Ma, creating thick sequences of conglomerate, mudstone, and carbonate rock topped by stromatolites, and possibly glacial deposits from the hypothesized Snowball Earth event. Rifting thinned huge roughly linear parts of the supercontinent Rodinia enough to allow sea water to invade and divide its landmass into component continents separated by narrow straits. A passive margin developed on the edges of these new seas in the Death Valley region. Carbonate banks formed on this part of the two margins only to be subsided as the continental crust thinned until it broke, giving birth to a new ocean basin. An accretion wedge of clastic sediment then started to accumulate at the base of the submerged precipice, entombing the region's first known fossils of complex life. These sandy mudflats gave way about 550 Ma to a carbonate platform which lasted for the next 300 million years of Paleozoic time.The passive margin switched to active margin in the early-to-mid Mesozoic when the Farallon Plate under the Pacific Ocean started to dive below the North American Plate, creating a subduction zone; volcanoes and uplifting mountains were created as a result. Erosion over many millions of years created a relatively featureless plain. Stretching of the crust under western North America started around 16 Ma and is thought to be caused by upwelling from the subducted spreading-zone of the Farallon Plate. This process continues into the present and is thought to be responsible for creating the Basin and Range province. By 2 to 3 million years ago this province had spread to the Death Valley area, ripping it apart and creating Death Valley, Panamint Valley and surrounding ranges. These valleys partially filled with sediment and, during colder periods during the current ice age, with lakes. Lake Manly was the largest of these lakes; it filled Death Valley during each glacial period from 240,000 years ago to 10,000 years ago. By 10,500 years ago these lakes were increasingly cut off from glacial melt from the Sierra Nevada, starving them of water and concentrating salts and minerals. The desert environment seen today developed after these lakes dried up.