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160 Cards in this Set
- Front
- Back
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What are the three different plate boundaries? |
Convergent Transform Divergent |
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Two plates that collide with each other, thrusting one plate on top of the other is called a _______________. |
Convergent plate boundary |
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Convergent plate boundaries are associated with what three faults? |
Thrust faults Reverse faults Strike - slip faults |
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How is a thrust fault formed? |
Caused by compression, one slab of rock slides on top of another at an angle less than 45° |
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How is a reverse fault formed? |
Caused by compression, one slab of rock slides on top of another at an angle greater than 45° |
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How is a strike-slip fault formed? |
One slab of rock slides past another laterally. |
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How are normal faults formed? |
Caused by gravity, one slab of rock pulls apart from another and slides downward with respect to the other slide. |
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What was the response by the scientific Community when Alfred Wegener published The Origin of Continents and Oceans in 1915? |
His ideas were generally viewed with disbelief, rejected, and considered improbable or impossible. |
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Wegener's early proposal of continental drift was not taken seriously because of his _____________. |
Failure to provide a plausible cause |
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The slowly increasing distance between South America and Africa is due to ___________. |
Seafloor spreading |
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Old Faithful Geyser at Yellowstone National Park in the United States acquire as its energy from a _________. |
Hot spot |
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Layered ____________ exposed by erosion can be seen when looking at the Grand Canyon in the United States. |
Sedimentary rock |
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Australia is composed of relatively old and thick _________. |
Continental crust |
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The extremely deep ocean Marianas Trench is a result of ___________. |
Subduction |
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_____________ found in the Atlantic Ocean between North America and Europe is composed of dense and relatively young rock. |
Seafloor crust |
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The earthquakes that occur in Southern California generally occur above a _________. |
Fault |
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Which moves faster, P waves or S waves? |
P waves |
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What are the four primary zones in Earth's interior? |
Crust, mantle, outer core and inner core. |
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What data provided information about the existence of different zones within earth? |
P wave and S wave |
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How do seismic waves move through Earth's interior? |
Seismic waves Move Along curved Ray paths because the properties of materials in the earth change |
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Why do we believe Earth's outer core is a liquid? |
P waves slow down and refract at the boundary between the mantle and the outer core. S waves do not travel through the outer core. |
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Why do geologists believe the inner core is solid? |
P waves refract at the boundary between the outer core and the inner core. |
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How could you test whether the core of another planet were completely solid? |
Set off a bomb to create seismic waves. If S waves arrive on the opposite side of the planet, then the core is solid. |
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How do plates move at divergent plate boundaries? |
Plates move apart |
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how do plates move at convergent plate boundaries? |
Plates move together |
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How do plates move at transform plate boundaries? |
Plates move side by side |
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Where do Both earthquakes and volcanic eruptions occur? |
At divergent and convergent plate boundaries |
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What forms at divergent plate boundaries? |
New Oceanic lithosphere |
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In general, where do volcanoes form in subduction zones? |
On the overriding play, away from the convergent boundary |
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Why are volcanoes not found at transform boundaries? |
Transform boundaries do not cause changes to the pressure, temperature, or composition of the mantle. |
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The East African Rift is a divergent plate boundary that is splitting the continent of Africa into two pieces. What will eventually form around this divergent boundary? |
An ocean |
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What is convection? |
A cycle of moving material formed by the rise of less dense material and the sinking of dense material |
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What accounts for most tectonic plate motion? |
Forces at subduction zones |
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What is the relationship between temperature and density? |
In general, warmer materials are less dense, and colder materials are denser |
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Which of the following terms best characterizes upwelling in the asthenosphere? Concentrated. Convective. Diverse. Diffuse. |
Diffuse |
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What is a plume? |
A zone of upwelling material originating at the outer core mantle boundary. |
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What features at the surface provide evidence of plumes? |
Hot spots |
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Earthquakes with a magnitude greater than 4.0 occur in a pattern that correlates closely with what? |
Plate boundaries. |
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Which plate boundary is NOT associated with volcanic eruptions? |
Transform |
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Which phenomenon can explain the presence of volcanoes in the middle of the Pacific Ocean? |
Hot spots |
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Which type of plate boundary is most closely associated with uplifting continental regions and mountain building? |
Convergent boundaries |
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Which evidence supports the theory of plate tectonics? |
The glomar Challenger found younger rocks and less sediment cover When approaching Oceanic ridges. |
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The current interest in continental drift was started with the notion of seafloor spreading, which was propounded by Hess and Dietz in the ________. |
1960's |
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If you travel away from a mid-ocean ridge you will find _________. |
Increasingly older rocks |
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Research since the 1970s has identified the cause of plate tectonics to be __________. |
Convection |
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Red indicates the youngest seafloor, Which is less than 2 million years old. Dark blue indicates the oldest seafloor, which is over a hundred and forty-four million years old. Sedimentary rocks of the Continental shelves are colored and light blue and are not considered part of the oceanic lithosphere. |
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1. Oceanic oceanic plate convergence: When two oceanic plates converge, the denser the two subducts into the mantle. The subduction results in the partial melting of lithospheric Rock above the area of subduction, leading to the formation of volcanoes. 2. Oceanic continental plate convergence: When an oceanic plate converges with a continental plate, the oceanic plate, being denser, subducts to form volcanic mountains. 3. Continental-continental plate convergence: When two continental plates converge, neither of them subducts as they have a density that is much lower than the mantle, resulting in the formation of collisional mountain chain. |
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Plate boundary convergence and the process of ___________ are responsible for the formation of the Andes Mountains -- a linear mountain range that parallels the western coast of South America. |
Subduction |
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New crust is created at a ___________ plate boundary, where plates are moving in opposite directions. |
Divergent |
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New oceanic crust formed at spreading centers creates topographic features on the ocean floor called _____________. |
Mid-ocean ridge |
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At a __________ plate boundary where the denser oceanic crust is recycled back into the mantle a physical features called a _________ is typical. |
Convergent, deep ocean trench |
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What is the relationship between the crust and the lithosphere? |
The crust is part of the lithosphere |
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Convergence is to moving away as convergence is to __________. |
Moving toward |
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Plates move apart at ___________ boundaries, move together at ____________ boundaries, and move side by side at ___________ boundaries. |
Divergent, convergent, transform |
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Which geologic features are associated with divergent boundaries? |
Mid ocean ridges and Continental rift valleys |
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Which geologic features are associated with convergent boundaries? |
Ocean trenches and volcanoes |
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Where is the youngest ocean floor found? |
Along the crest of mid-ocean ridges |
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What would happen to Earth if ocean floor were created at divergent boundaries at a faster rate than it is destroyed at convergent boundaries? |
Earth would increase in volume |
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What is a volcanic Arc? |
A row of volcanoes that forms on the over-riding plate near a subduction zone |
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Which of the following mountain ranges are examples of Continental arcs? East African Rift and Hawaii. East African Rift and Cascades. Andes and Hawaii. Andes and Cascades. |
Andes and Cascades |
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Which feature is found at a divergent boundary? |
A rift valley |
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Which location is the result of oceanic continental convergence? |
The Cascades and mount st. Helens |
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What differentiates Oceanic Oceanic convergent plate boundaries from oceanic continental convergent boundaries? |
Volcanic island arcs |
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Where is one plate being subducted under another plate? |
Along the Aleutian Trench |
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The Himalayas were formed by crumpling of plate edges in a _________ Zone. |
Convergent |
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Which of the following is most closely associated with a mantle plume? The Hawaiian Islands. The lower Mississippi River Valley. Southern California. Western Europe. The Florida Peninsula. |
the Hawaiian Islands |
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What is the term for a piece of crust which has been in a collision along a convergent crustal boundary and become accreted to another crustal plate? |
Terrane |
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What geologic process is related to caldera formation? |
Volcanism |
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How do calderas form? |
Calderas form when the summit of a volcano collapses |
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Where is Crater Lake? |
Oregon |
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In addition to rock deposits what evidence do we have that the eruption that preceded the formation of Crater Lake was very large? |
The eruption was so large that the magma chamber under Crater Lake partially empty, causing the volcano to become unstable and collapse. |
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Why does Crater Lake have an island in it? |
The volcano is still active, and a new volcanic Peak has formed. |
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Which of the following are types of volcanoes? Shield volcano Cinder cone Composite volcano Cinder volcano Caldera |
Shield volcano Cinder cone Composite volcano |
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What information do geologists use to classify volcanoes? |
Shape and type of deposits |
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Cinder cones are made of __________. |
Pyroclastic deposits |
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In general how often do most Cinder cones erupt? |
Most Cinder cones erupted once. But a single eruption can last decades. |
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What are shield volcanoes generally made of? |
Basalt flows |
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What is the range of shield volcano height? |
300 - 10000 meters |
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What are composite volcanoes made of? |
Pyroclastic deposits and Basalt flows |
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Why are shield volcanoes wider than composite volcanoes? |
The lava that flows out of shield volcanoes is more fluid than the lava that flows out of composite volcanoes. |
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What type of magma erupts out of dome complexes? |
Felsic magma |
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What type of volcanoes are the tallest? |
Shield volcanoes |
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What is the range of Dome complex height? |
500 - 2000 meters |
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What type of volcano is Mount Fuji, the classic icon of Japan? |
Composite cone |
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Which of the following is not an intrusive volcanic landform? Sill Vein Batholith Batholith CalderaDike Caldera Dike |
Caldera |
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Flood basalts cover much of the ocean floor, India, and North America, the ___________. |
Columbia Plateau |
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Mt. St. Helens is __________. |
Likely to vigorously erupt again. |
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The nature of a volcanic eruption is a tournament largely by the ___________ of the magma. |
Chemistry |
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Which of the following are waves generated by earthquakes? Pyroclastic flows. Tsunamis. Plutons. Monoclines. Larhars. |
Tsunamis |
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Lava flows often create _________. |
Flat Plains |
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___________ is an area of extensive flood basalts. |
The Columbia Plateau |
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What type of volcano is Mount st. Helens? |
Composite |
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Which of these most directly triggers the main eruption? |
A massive landslide |
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There have been many earthquakes in the area prior to this eruption. Why did this last earthquake trigger a massive landslide? |
Moving magma had overteepend the mountain slopes |
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If previous eruptions had left Mount Saint Helens with a different shape, what differences might have influenced the timing of the eruption? |
If the northern slopes have been less steep initially (same height), the eruption would likely have happened later. If the volcano had been significantly shorter initially (same steepness), the eruption would have likely happen sooner. |
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How much material was removed from Mt. St. Helens? |
2.8 cubic kilometers of Rock |
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What is a fault? |
Fractures along which rocks move |
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What are rocks below and above a fault called? |
The football below and the hanging wall above |
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What are rocks below and above a fault called? |
The football below and the hanging wall above |
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What type of force is responsible for normal fault formation? |
Tensional Force |
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Which type of force is responsible for reverse fault formation? |
Compressional Force |
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Which type of force is responsible for normal strike-slip formation? |
Shear force |
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Which type of fault has no vertical motion of rocks associated with it? |
Strike slip fault |
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A ________ is the same thing as pyroclastic flow. |
Nuée ardente |
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A volcanic mudflow is known as a ___________. |
Lahar |
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What lies underneath volcanic features at Earth's surface? |
Magma Chambers in volcanic conduits |
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What is the difference between a dike and a Sill? |
A dike intrudes across sedimentary layers, and a sill intrudes between sedimentary layers. |
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What is a volcanic conduit called after the conduit has solidified and been exposed by erosion? |
A volcanic neck |
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Why are volcanic rocks often exposed at Earth's surface as Hills, ridges, and mountains surrounded by areas of lower elevation? |
Volcanic rocks are often more resistant to erosion that surrounding Rock. |
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What is a magma chamber called after it and the conduit have solidified and been exposed by erosion? |
A batholith |
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What is the igneous body shown in the cross section? |
Dike |
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The most massive form of igneous intrusion is a __________. |
Batholith |
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which type of force causes folding? |
Compressional Force |
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What is an anticline? |
A fold shaped like an upside down U |
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What is a syncline? |
A fold shaped like a right side up U |
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Imagine that an anticline has been eroded to a flat surface. How would the rock age change as you walked across the flat surface? |
Rocks with the youngest on the edges and oldest in the middle |
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Imagine that a syncline has been eroded to a flat surface. How would the rock age change as you walked across the flat surface? |
Rocks would be oldest on the edges and youngest in the middle |
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What produces plunging Folds? |
A combination of folding and tilting |
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What does the term plunging fold mean? |
A cold that is tilted down into the Earth |
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Imagine that a fold has been eroded to a flat surface. In general, how would you know if this fold is plunging? |
Non plunging folds look like straight lines at the surface, and plunging folds look like wavy lines. |
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Unfolded to rain, a simple symmetrical down fold is termed a ________. |
Syncline |
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A simple symmetrical upfold is called a _________. |
Anticline |
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Augusta block which is down thrown with a steep fault scarp on either side is a _________. |
Graben |
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Grabens are commonly found an association with ___________. |
Horsts |
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Which of the following are fault block mountains? Appalachians. Cascades. Ozarks. Rockies. Sierra Nevada. |
Sierra Nevada |
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Which situation would result with older sediments overlying younger sedimentary rocks? |
Thrust faulting |
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Which of the following refers to the surface of Earth directly above the center of an earthquake? Hotspot. Nadir. Epicenter. Seismic Zone. Focus. |
Epicenter |
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Loose, water-saturated sediments May undergo ___________ during an earthquake |
Liquefaction |
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About how much more energy is released during a magnitude 6 earthquake than during a magnitude-5 earthquake? |
32 times |
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What are the types of mountain glaciers, and how are they related? |
A cirque Glacier can become a Valley Glacier and then a piedmont glacier. |
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Continental ice sheets smooth and round the train while Mountain glaciations tend to ______________. |
Steepen slopes and increase local relief |
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In glacially influenced mountain valleys are ___________ lakes which are series of shallow Lakes which bear a fancy resemblance to beads on a rosary. |
Paternoster |
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During the Pleistocene, ____________ was a time of ice retreat. |
An interglacial |
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The Earth has been deglaciating for the last _______ years. |
9,000 |
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The time since 10,000 B.C. is most properly known as the _________ epoch. |
Holocene |
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During the last ice age, sea level was _________. |
Much lower than today sea level |
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Where do glaciers form? |
In places where more snow falls in the winter than melt away in the summer |
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What is the snow line? |
The elevation above which snow persists throughout the year |
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What is the zone of wastage? |
The part of a glacier where snow melting exceeds snow accumulation |
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Under what conditions will the front of a glacier remain stationary? |
Glacial fronts remain stationary when melting and snow accumulation are equal |
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What is an end moraine? |
a rigid debris deposited at the end of a glacier |
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How does an end moraine form? |
Pieces of rock are transported to the front of a glacier as ice within the glacier moves. |
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Will plucking occur if a glacier is not advancing? |
Yes, because glacial ice is still moving inside the glacier even if the glaciers front is not advancing. |
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Which demonstration illustrates best how a glacier moves? |
Smash a ball of clay against a gravel driveway surface, and watch the clay spread. |
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What is the impact on a glacier in a year when melting exceeds snowfall? |
The area of the glacier shrinks. |
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_________ is granular snow which is beginning to coalesce into glacial ice. |
Névé |
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The lower part of a glacier where there is a net annual loss of ice from melting and sublimation is the zone of __________. |
Ablation |
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Snow is changed by ________ into glacial ice. |
Pressure and weathering |
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The movement of a glacier along its bottom, lubricated by meltwater, is known as __________. |
Basal slip |
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The glacial scouring by Bedrock embedded in ice is erosion by __________. |
Abrasion |
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Drift is ________. |
A term which is a misnomer out of biblical literature |
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What is a mountain that has been eroded on all sides by at least three cirque glaciers? |
Horn |
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What is the ocean fill portion of a previously glaciated Valley called? |
Fjord |
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Ad glaciated cirque often contains a basin in which a _________ can be found. |
Tarn |
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Glaciers carve _______ - shaped valleys. |
U |
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The maximum extent of a glacier is marked by a __________. |
Terminal moraine |
