Understanding Plate Tectonics and Earth's Structure

What is the primary difference between oceanic and continental crust?

• Oceanic crust is thicker than continental crust.

• Continental crust is denser than oceanic crust.

• Oceanic crust is primarily composed of lighter silicates.

• Oceanic crust is thinner and denser than continental crust.

What role does the asthenosphere play in plate tectonics?

• It is a rigid layer that prevents plate movement.

• It is a partially molten layer that allows plates to move.

• It is a liquid layer that forms new crust.

• It is a solid layer that supports the lithosphere.

How does mantle convection influence tectonic plate movement?

• It cools the Earth's core, slowing plate movement.

• It creates currents that drive plate movement.

• It generates heat that melts the lithosphere.

• It causes plates to remain stationary.

Why is Iceland geologically significant?

• It is the only place with no tectonic activity.

• It is the only place where the mid-ocean ridge is visible above sea level.

• It is the largest island formed by volcanic activity.

• It has the oldest oceanic crust on Earth.

What are hydrothermal vents and where are they commonly found?

• They are deep-sea trenches found in subduction zones.

• They are volcanic eruptions found on land.

• They are hot water geysers found at mid-ocean ridges.

• They are cold water springs found in continental crust.

What happens at a subduction zone?

• Two oceanic plates converge and form a mountain.

• An oceanic plate slides beneath a continental plate.

• A continental plate slides over another continental plate.

• Two continental plates diverge.

Which of the following is a result of subduction?

• Expansion of continental crust.

• Creation of deep ocean trenches.

• Formation of mid-ocean ridges.

• Formation of transform faults.

What is the significance of the Mariana Trench?

• It is the widest oceanic ridge.

• It is the largest volcanic island chain.

• It is the deepest point on Earth's surface.

• It is the highest point on Earth's surface.

What geological feature is commonly associated with subduction zones?

• Shield volcanoes

• Mid-ocean ridges

• Transform faults

• Volcanic mountain chains

How do subduction zones contribute to volcanic activity?

• They melt oceanic crust, forming magma.

• They create pressure that forms new crust.

• They cool the mantle, preventing eruptions.

• They cause continental crust to sink.