CH 18 Quiz

What would explain how Earth developed a layered internal structure? Earth melted and heavier material sank toward the center and different densities of materials formed layers. Earth was formed as less dense materials were attracted to more dense accumulation, which formed layers. Earth was formed by gravitational attraction of different materials, which formed layers as it clumped together.

Earth melted and heavier material sank toward the center and different densities of materials formed layers.

An island arc, such as the Aleutian Islands, is a curving chain of volcanic islands that occur near what type of plate boundary? divergent boundary transform boundary convergent boundary new boundary

convergent boundary

What is a plate boundary where two plates are moving toward one another? new boundary convergent boundary divergent boundary transform boundary

convergent boundary

Which part of the earth makes up about one-third of earth's total mass and is mostly iron with a solid part and a part that acts like a liquid? core mantle crust asthenosphere

core

Which part of Earth is a thin skin that covers the entire surface, existing beneath oceans as well as making up the continents? mantle crust asthenosphere core

crust

What is a plate boundary where two plates move away from each other as new crust is formed between them? transform boundary divergent boundary convergent boundary new boundary

divergent boundary

What is the origin of the magnetic strip patterns found in rocks along an ocean ridge? earthquakes caused the crust of Earth to move toward, then away from the ridge new crust moving from the ridge becomes magnetized in different directions as the magnetic field of Earth flipped magnetic materials naturally lose their magnetism over a long period of time, which causes strips to lose their orientation All of the above.

new crust moving from the ridge becomes magnetized in different directions as the magnetic field of Earth flipped

Why are island arcs formed near a place of ocean-ocean plate convergence? subduction does not occur and colliding plates push up lighter matter that melts, then forms islands subducted material becomes melted, rising through the overriding plate to form islands island arcs form along a diverging boundary where hot asthenosphere wells upward, forming volcanic mountains

subducted material becomes melted, rising through the overriding plate to form islands

What is a plate boundary where two plates slide past each other? transform boundary divergent boundary new boundary convergent boundary

transform boundary

What evidence provides information about the nature of the earth's core? earthquake waves the nature of meteorites mass of the earth All of the above.

All of the above.

How does plate tectonics account for the existence of certain geologic features? subduction of one plate beneath another will explain volcanoes colliding plates can explain how mountain ranges are formed new crust is created in suboceanic divergence boundaries All the above.

All the above.

Why are ancient rocks not found on the seafloor? older seafloor is plowed under the edge of continents in subduction zones new seafloor is created in ocean ridges and moves toward continents older rocks do not have time to accumulate on the moving seafloor All the above.

All the above.

According to the accepted theory, Earth has a core composed mostly of iron because Earth melted and centrifugal force moved lighter elements to the crust. Earth melted and the heavier iron sank and accumulated near the center. the iron core formed first, and lighter elements were accumulated later. iron migrated through solid materials to end up at what is now the core.

Earth melted and the heavier iron sank and accumulated near the center.

What is the probable source of most earthquakes that occur in southern California? The Juan de Fuca Plate moving under the North American Plate. The San Andreas Fault, which is a transform boundary between the Pacific Plate and the North American Plate. The North American plate being pushed across a weak asthenosphere. California is breaking off the continent and will slide into the ocean.

The San Andreas Fault, which is a transform boundary between the Pacific Plate and the North American Plate.

How is continental drift different from plate tectonics? there was not a reason given for continents to move continental drift considered only continents to move continents moved as a breakup of a single large landmass

all

Rocks, sediments, and fossils around an ocean ridge have a pattern concerning their ages. What is the pattern? all are older as you move away from the ridge all are younger as you move away from the ridge all are the same age as you move away from the ridge

all are older as you move away from the ridge

An oceanic trench is a region of great depth that marks where two continental plates slide by one another. two oceanic plates slide past one another. two continental plates collide. an oceanic plate is forced beneath a continental plate.

an oceanic plate is forced beneath a continental plate.

The lithosphere is broken into a number of fairly rigid plates that move in what part of the earth? outer core inner core crust asthenosphere

asthenosphere

Which part of the earth is a hot, elastic semi-liquid layer that extends around the entire Earth? core crust mantle asthenosphere

asthenosphere

Which of the following is a part of the mantle below the lithosphere and is a relatively thin plastic layer? mantle lithosphere asthenosphere crust

asthenosphereWhich of the following is the outer layer of Earth that includes the Moho? crust asthenosphere lithosphere mantle

The early idea that individual continents could shift positions on Earth's surface was called continental plate movement. shifting land movement. tectonic drift movement. continental drift.

continental drift.

Which of the following includes the entire crust, the Moho, and the upper part of the mantle? crust lithosphere asthenosphere mantle

lithosphere

Which of the following is the outer layer of Earth that includes the Moho? crust asthenosphere lithosphere mantle

lithosphere

Which of the following contains part of the lithosphere, all the asthenosphere, and has a solid, dense lower part? mantle lithosphere asthenosphere crust

mantle

Which part of Earth accounts for about two-thirds of its total mass and is mostly silicate minerals such as olivine? core mantle asthenosphere crust

mantle