Understanding Ocean Floor Geology and Ocean Properties

What is the solid, outermost layer of the ocean floor called?

• Magma

• The oceanic crust

• Continental crust

• Asthenosphere

Which layer of the Earth sits directly below the ocean floors?

• Upper mantle

• Atmosphere

• Inner core

• Outer core

What is the process called when ocean floor spreads apart along a mid-ocean ridge?

• Subduction

• Sea-floor spreading

• Erosion

• Plate tectonics

Why does seawater taste salty?

• It absorbs coastal waters

• Fish release salts

• The oceanic crust is salty

• It contains dissolved salts and minerals.

What causes ocean currents to move in different directions?

• Gravity alone

• Tides only

• Friction with the moon

• The Earth's rotation and wind patterns

Which type of ocean current carries warm water from the equator toward the poles?

• Deep currents

• Tidal currents

• Surface currents

• Countercurrents

Which feature of the ocean floor is the deepest part of the ocean?

• Continental shelf

• Rift valley

• Mid-ocean ridge

• Trench

How does the salinity of ocean water affect its density?

• Higher salinity decreases water density.

• Salinity does not affect density.

• Higher salinity increases water density.

• Higher salinity makes water less dense.

What is the main reason ocean water is able to support such a wide range of life forms?

• It is cool and refreshing.

• It is warm all year round.

• It is always shallow.

• It is nutrient-rich.

Which ocean zone receives the most sunlight?

• Abyssal zone

• Hadal zone

• Bathypelagic zone

• Epipelagic zone