Earth's Layers and Plate Tectonics

Based on the given data on the Earth's layers, as you move deeper into the Earth, what happens to the density?

• A. It remains constant.

• B. It decreases.

• C. It increases.

• D. It fluctuates inconsistently.

Using the data on Earth's layers, which layer is the least dense?

• A. crust

• B. mantle

• C. outer core

• D. inner core

Which statement accurately describes the inner and outer cores of the Earth?

• A. The outer core is solid, while the inner core is liquid.

• B. The inner core is more dense than the outer core.

• C. The outer core is primarily made of granite.

• D. Both the inner and outer cores are of the same density.

When one plate subducts, or goes under, another plate, which is the plate that subducts (or goes underneath the other?)

• A. The lighter plate.

• B. The continental plate.

• C. The heavier and denser oceanic plate.

• D. They both undergo subduction.

An image shows a deep ocean trench with one plate sliding under another. What process is being depicted?

• A. subduction of a continental plate beneath an oceanic plate

• B. subduction of an oceanic plate beneath a continental plate

• C. two oceanic plates moving apart from each other

• D. two continental plates colliding and neither subducting

When two continental plates converge, what feature is most likely formed?

• A. Deep-sea trench

• B. Oceanic ridge

• C. Volcanic island arc

• D. Mountain range

How do convection currents in the mantle primarily affect tectonic plates?

• A. They pull plates down into the mantle.

• B. They cause plates to melt and reform.

• C. They cause plates to move due to the rising and sinking of heated and cooled material.

• D. They have no effect on plate movements.

The Grand Canyon was formed primarily by which geologic process?

• A. Convergent plate boundary movement

• B. Transform plate boundary movement

• C. Divergent plate boundary movement

• D. Erosion due to the Colorado River

If a volcanic island chain forms in the middle of an ocean, which tectonic process is most likely responsible?

• A. Two continental plates colliding

• B. An oceanic plate subducting under a continental plate

• C. Two oceanic plates diverging

• D. Two oceanic plates converging

What drives the movement of Earth's tectonic plates?

• A. Gravitational pull from the moon

• B. Expansion and contraction due to day and night temperature differences

• C. Convection currents within the Earth's mantle

• D. Magnetic forces from the Earth's poles