Mastering Assignment Geo Chapter 13 & 14
Which type of volcanic material will dominate the eruptions along a continental volcanic arc?
Andesitic lavas and pyroclastic materials
What kind of magma is initially generated in a subduction zone?
Basaltic
Which U.S. region is made up of a series of half-grabens producing nearly parallel mountain ranges?
Basin and Range
The measurement of ocean depth and the topography of the ocean floor are known as ________.
Bathymetry
Submarine canyons found cutting into the continental shelf and slope are believed to have been created ________.
By rivers during the ice age
________ contain large quantities of preexisting sedimentary and crystalline rocks that have been faulted and contorted into a series of folds.
Compressional mountains
Which is a feature of a passive continental margin?
Continental rise, Continental slope
Why would geologic mapping be difficult in an area dominated by accreted terranes?
Each terrane is geologically distinct, but also highly deformed
Most mountain ranges formed through cooling of the Earth's crust, which resulted in wrinkling as it contracted
False
Which of the following terms describes the increasing downward force on basal rocks as a mountain continues to grow?
Gravitational collapse
Which of the following best describes the effect of convective flow on the elevation of Earth's major landforms?
Hot rising material upwarps the landscape whereas downward flow causes downwarping
The map in Figure 2 is a cross-section of the North American continent 600 million years ago and after the break-up of Pangaea approximately 200 million years ago. Which material(s) had been accreted to North America as terranes?
Iapetus Ocean Island Arc and sediments, the Avalon Terrane, and a remnant of Africa
_____ is the principle that explains why materials uplift to a certain elevation.
Isostasy
What causes mountain formation in a continental rifting setting
Lithospheric blocks, bounded by normal faults, tilt and rise.
______ play a role in the break-up of supercontinents, like Pangaea.
Mantle plumes
The steepest angle of subduction of oceanic plates can be found at _______.
Mariana's Trench
What happens as plates diverge at an oceanic ridge?
New oceanic crust and lithospheric mantle are generated by the cooling of molten rock upwelling from the mantle.
are composed of flood basalts.
Oceanic plateaus
How can subduction result in the emplacement of batholiths?
Partial melting of the subducting plate creates magma
What is the definition of orogenesis?
Processes that collectively form a mountain belt
Which seafloor mapping method can map the largest extent of seafloor in the shortest amount of time?
Satellites with radar altimeter
Which of the following best explains why some fault-block mountains have an elevated topography?
Stretching and thinning of the lithosphere allowed for it to sit higher on the mantle
Which of the following accurately compares the Mid-Atlantic Ridge and East Pacific Rise?
The Mid-Atlantic Ridge is spreading at a much slower rate than the East Pacific Rise.
Using what you know about isostasy, how would the crust behave if a large glacier were removed?
The crust would move up in elevation.
If the Rocky Mountains were eroded, what would happen to the roots of the mountains?
The roots would rebound upward.
What is a suture?
The zone where two continents are welded together
________ accounts for greater ocean depths moving away from the oceanic ridge toward the deep ocean basin.
Thermal contraction
Using the map in Figure 1, determine which of the named terranes accreted earliest to North America.
Yukon-Tanana
A terrane is __________.
a mass of rock that formed elsewhere and was added to a continent
What are the features associated with a divergent boundary that is spreading quickly
a relatively smooth swell with gentle slopes
What is the name of the process by which terranes are added to continents
accretion
Which tectonic boundary is associated with the addition of terranes to a continent?
convergent boundary
Which geologic features would be present in compressional mountain belts?
folds, intrusive igneous rocks, thrust faults
creep
gradual downhill movement of soil and regolith.
slump
involves a downward sliding of a mass of rock or unconsolidated material moving as a unit along a curved surface -- creating a crescent shape at the head.
Which of the following contains the entire ophiolite suite, in order from the mantle to the seafloor?
mantle peridotite, gabbro, sheeted dike complex, pillow lavas, deep-sea sediments
slide
mass movements in which there is a distinct zone of weakness separating the slide material from the more stable underlying material. Movement does not occur on a curved surface.
flow
material moves downslope as a viscous fluid.
fall
movement in a mass-wasting event involves the free fall of detached individual pieces of any size. This occurs on very steep slopes.
Hydrothermal vents are a feature of ______.
oceanic ridges
What two layers of the ophiolite sequence are compositionally similar, but formed in different areas with respect to the crust
pillow lavas and gabbro
Which of the following rocks are characteristic of compressional mountain building?
schist
An example of a failed continental rifting center is _______.
the Keweenawan Rift
A passive continental boundary is located hundreds of miles away from the nearest tectonic boundary
true
Continental shelves can be exposed during glaciations because of the large volumes of water taken from the ocean to precipitate as ice and snow
true
The greatest volume of magma produced annually on Earth is associated with seafloor spreading and oceanic ridges.
true
Which of the following scenarios could result in the development of a compressional mountain belt?
two landmasses collide
Batholiths, such as those that make up the Sierra Nevada Mountains of California, form at great depth in the crust. How could they have been exposed at the surface?
uplift and erosion
Using the map provided in Figure 1, in which province would the Rocky Mountains of the United States be located
young mountain belts