9.2 Seafloor Spreading Learning Check

What causes the seafloor to spread?

• rising molten magma

• drifting continental crust

• sinking magma

The thickness of oceanic crust close to a mid-ocean ridge is __________ the thickness of oceanic crust far away from a mid-ocean ridge.

• more than

• less than

• equal to

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS2-1

Henry Hess created the theory of _____________

• plate tectonics

• seafloor spreading

• continental movement

Tags

NGSS.MS-ESS2-3

Select the two types of crust. (pick 2 answers)

• oceanic

• volcanic

• continental

The further the ocean floor is away from the mid-ocean ridge, the __________ that floor will be.

• older

• newer

• prettier

Tags

NGSS.MS-ESS2-3

Which describes the movement at a mid ocean ridge?

• plates are moving toward each other

• plates are moving away from each other

• plates are moving past each other

Tags

NGSS.MS-ESS2-3

Which is more dense?

• Oceanic crust

• Continental crust

• Sedimentary Crust

Seafloor spreading happens because ________.

• earthquakes break the ocean floor

• magma rises from the mantle to the surface

• sediments build up near the spreading

Tags

NGSS.MS-ESS2-1

A large, underwater mountain chain is called.........

• oceanic crust

• deep sea trench

• mid-ocean ridge

Tags

NGSS.MS-ESS2-3

The magnetic pattern of ocean-floor rocks on one side of an ocean ridge is...........

• a mirror image

• much different

• at right angles

Tags

NGSS.MS-ESS2-3