BYU Earthscience Part 1 Locking in

Scientists expected ocean floors to have a thick layer of sediment; however, when they checked, they discovered that ocean floors have very thin layers of sediment. What did this tell them about ocean floors?

• There is a lot of wave action that stops sediment from settling on the seafloor.

• Continental land is not eroding as quickly as scientists thought it was.

• There are no volcanoes in the ocean.

• Ocean floors are not as old as they thought they were.

Ocean floors are not as old as they thought they were.

Which of the following best summarizes the plate tectonic theory?

• Billions of years of earthquakes and volcanoes have divided Earth’s crust into large and small pieces.

• Earth is divided into pieces that go deep to its core; the pieces are pushed around by lava from the earth’s core. Earth is divided into pieces that used to move, forming trenches, mountains and ridges, but the pieces do not move anymore.

• Earth’s crust is divided into moving pieces that collide with each other, creating mountain ranges, ocean ridges, and ocean trenches.

Earth’s crust is divided into moving pieces that collide with each other, creating mountain ranges, ocean ridges, and ocean trenches.

Where are two ocean plates diverging?

A

Where is new crust being created?

A

Where are two continental plates converging?

B

Where is crust being destroyed?

D

Upon which layer of the earth do the plates rest and move?

• mantle

• asthenosphere

• outer core

• lithosphere

asthenosphere

According to Alfred Wegener’s theory of continental drift, how were all of the continents originally arranged?

• All continents were in the southern hemisphere.

• All continents were located opposite of where they are now.

• All continents were part of a large mass of land he called Pangaea.

• All continents were in the northern hemisphere near ice-covered Greenland.

All continents were part of a large mass of land he called Pangaea.

In which of the following types of plate boundaries is new crust formed?

• ocean-continent convergent boundary

• continent-continent convergent boundary

• divergent boundary

• transform boundary

divergent boundary

Besides the discovery of coal in Greenland, what other evidence did Alfred Wegener have to prove his continental drift theory?

similar fossil records on different continents

Which type of boundary is not shown on the map?

• convergent

• collision

• divergent

• transform

transform

In what direction is the plate with the volcanoes moving?

• south

• west

• north

• east

east

Where would be the safest place to build a bridge?

• between B and D

• between C and D

• between F and C

• between G and E

between F and C

Why does the crust have high continents and low ocean basins?

• Density differences between continental rock and oceanic rock mean that the continents float higher in the asthenosphere than the oceanic rock.

• The asthenosphere is thicker under the continents and thinner under the oceans.

• The ocean basins are large impact craters that were formed by the last few planetesimals that hit the earth’s early crust.

• Oceanic crust is older than the continental crust, so oceanic crust must be underneath continental crust.

Density differences between continental rock and oceanic rock mean that the continents float higher in the asthenosphere than the oceanic rock.

Why does the crust have high continents and low ocean basins?

• Density differences between continental rock and oceanic rock mean that the continents float higher in the asthenosphere than the oceanic rock.

• The asthenosphere is thicker under the continents and thinner under the oceans.

• The ocean basins are large impact craters that were formed by the last few planetesimals that hit the earth’s early crust.

• Oceanic crust is older than the continental crust, so oceanic crust must be underneath continental crust.

Density differences between continental rock and oceanic rock mean that the continents float higher in the asthenosphere than the oceanic rock.

The Himalayan mountain range is being formed by the convergence of which two tectonic plates?

The Eurasian and Indian Plates

the North American and Pacific Plates

the Antarctic and South American Plates

the Eurasian and African Plates

the Eurasian and Indian Plates

The earth developed a layered structure because of

changes in chemical/mineral composition

changes in the density of the internal material

changes in the physical state (solid liquid) of the material

all of these factors

all of these factors

Which of the following best explains the formation of the Japanese Islands?

The islands are the result of a rift in the Eurasian plate.

The islands are the result of a divergent boundary between the Pacific and Eurasian Plates.

The islands are in the middle of the Eurasian Plate and were formed like Hawaii—a result of hot spots.

The islands are the result of a convergent boundary between the Pacific and the Eurasian Plates.

The islands are the result of a convergent boundary between the Pacific and the Eurasian Plates.

Why didn’t scientists believe Alfred Wegener’s theory of continental drift?

The fossil record of different continents did not support Wegener’s theory

Wegener had a reputation for exaggerating information

Wegener had no explanation for what made the continents drift (or move)

The rock and mineral patterns of different continents didn’t support Wegener’s theory

Wegener had no explanation for what made the continents drift (or move)Why does the ocean plate always subduct when it converges with a continent plate?

Why does the ocean plate always subduct when it converges with a continent plate?

• because the ocean crust is magnetically pulled under the continent

• because the ocean crust is older and ready to be subducted

• because the ocean crust is already lower than the continent

• because the ocean crust is heavier than continent crust

because the ocean crust is heavier than continent crust

How would you explain the formation of the Hawaiian Islands in the middle of the Pacific Plate?

The Pacific Plate is actually two plates converging together, creating mountains, and the Hawaiian Islands are actually the tops of these mountains.

The Pacific Plate is actually two plates that are diverging, creating a tall ridge, and the Hawaiian Islands are the highest parts of this ridge.

The Hawaiian Islands are the tops of volcanic mountains formed by hot spots under the Pacific plate; as the plate moves, the hot spots create new islands.

The Hawaiian Islands are the last bit of land left after the separation of the South American Plate and the Australian Plate—they will eventually disappear.

The Hawaiian Islands are the tops of volcanic mountains formed by hot spots under the Pacific plate; as the plate moves, the hot spots create new islands.

How do the magnetic patterns on the seafloor support the theory of tectonic plates?

The magnetic patterns prove that the seafloor is old, which is what the plate tectonic theory suggests.

The magnetic patterns prove that the seafloor does not move; only the continents do.

The magnetic patterns on each side of the ocean ridge are symmetrical, which proves that the seafloor is spreading.

The magnetic patterns are formed by earthquakes, which the plate tectonic theory says occur in oceans.

The magnetic patterns on each side of the ocean ridge are symmetrical, which proves that the seafloor is spreading.

Which layer of the earth is not matched with its correct physical state?

crust—solid

asthenosphere—plastic-like

outer core—solid

inner core—solid

outer core—solid

How do volcano and earthquake patterns support the idea of plate tectonic theory?

They are usually found near the borders of plates, which is where plates slide against each other and create stress in the crust.

Most are found on larger continents, and according to the theory, larger continents are still in the process of breaking up.

They are usually found in the center of plates, which is where plates are coming apart and experiencing a lot of stress.

They are usually found on land, which is where plates are coming apart and experiencing a lot of stress.

They are usually found near the borders of plates, which is where plates slide against each other and create stress in the crust.

The state of balance between the thickness of the crust and the depth at which it floats on the asthenosphere is called

stress

strain

shearing

isostasy

isostasy

In which direction is the continent of North America moving?

toward the Pacific Ocean

toward the Atlantic Ocean

toward South America

toward Europe

toward the Pacific Ocean

In which of the following types of plate boundaries is the crust neither created nor destroyed?

ocean-continent convergent boundary

transform boundary

continent-continent convergent boundary

ocean-ocean convergent boundary

transform boundary

Africa is famous for its gold mines. According to evidence that supports the theory of plate tectonics, where would be the best place to look for similar deposits of gold?

A

B

C

D

B

Which mountain range is being created by the convergence of the Nazca and South American plate?

Ural

Rocky Mountain

Andes

Appalachian

Andes

Why are mountain ranges created where two continental plates converge?

Neither plate is subducted; instead, both are lifted up forming a mountain range.

One plate is subducted—pushing the crust of the other plate up.

One plate is subducted, but its crust remains to form a mountain range.

Both plates are subducted—forcing the land up around them.

Neither plate is subducted; instead, both are lifted up forming a mountain range.

Why would the discovery of coal in Greenland be evidence for Alfred Wegener’s theory of continental drift?

Coal is normally found in cold climates; Greenland is not cold enough.

Coal is found in places where jungles used to be; Greenland must have been closer to the equator where jungles are common.

Coal is only found in Antarctica; Antarctica and Greenland must have been connected in the past.

Coal is only found in North America; Greenland and North America must have been connected in the past.

Coal is found in places where jungles used to be; Greenland must have been closer to the equator where jungles are common.

What geologic feature is created when an ocean plate converges with another ocean plate or a continent plate?

rift

trench

mountain range

high plateau

trench

The Caribbean plate is merging with which other plate to form the Caribbean Islands?

the Antarctic Plate

the Eurasian Plate

the North American Plate

the Pacific Plate

the North American Plate

The North American and Eurasian plates are diverging. What physical evidence proves this?

the Appalachian Mountains

the mid-Atlantic ridge

The island of Great Britain

the Rocky Mountains

the mid-Atlantic ridge

Which sphere is not correctly matched?

atmosphere—all the gases of the earth

hydrosphere—the earth’s water

lithosphere—the earth’s solid rock/crust

asthenosphere—all the molten rock inside the earth

asthenosphere—all the molten rock inside the earth

When an ocean plate and a continent plate converge, which plate subducts?

the continent plate

neither plate subducts

both plates subduct

the ocean plate

the ocean plate

In which of the following types of plate boundaries are continental mountain ranges created?

ocean-ocean convergent boundary

divergent boundary

continent-continent convergent boundary

transform boundary

continent-continent convergent boundary

Which of the following best describes what happens at a divergent plate boundary?

The plates smash together and create mountains because neither plate is subducted.

The plates move together and a trench is formed where one plate subducts.

The plates separate from each other creating new seas or lakes.

The plates separate from each other creating new crust in the process.

The plates separate from each other creating new crust in the process.