L7.2 Tectonic Plate Movement Mechanisms

What was Alfred Wegener's primary proposal regarding continents?

• That continents are fixed in their current positions.

• That continents fit together like a puzzle and moved apart over time.

• That continents are constantly growing in size.

• That continents are slowly sinking into the ocean.

What was the main challenge Alfred Wegener faced with his continental drift theory?

• He couldn't explain the composition of the continents.

• He couldn't explain how the plates moved apart.

• He couldn't explain the age of the continents.

• He couldn't explain the types of rocks found on different continents.

How many mechanisms have scientists proposed to explain the movement of tectonic plates?

• Two

• Three

• Four

• Five

Which of the following is NOT one of the proposed mechanisms for tectonic plate movement?

• Mantle Convection

• Ridge Push

• Core Expansion

• Slab Pull

What happens to magma as it rises to the Earth's surface during mantle convection?

• It becomes hotter and more dense.

• It cools and sinks back down.

• It solidifies and stops moving.

• It evaporates into the atmosphere.

What causes the "ridge push" mechanism in plate tectonics?

• The pulling force of a subducting plate.

• The upward movement of cold, dense rock.

• The force of newly formed, warmer, less dense rock at mid-ocean ridges pushing older, denser rock away.

• The sideways movement of plates due to friction.

What is the primary force driving "slab pull" in plate tectonics?

• Magnetic forces within the Earth's core.

• The buoyancy of oceanic crust.

• Gravity pulling a dense, subducting plate into the mantle.

• The expansion of magma at mid-ocean ridges.

What is "slab suction" caused by?

• Large-scale convection currents in the entire mantle.

• A small-scale convection current in the mantle wedge.

• The direct pull of the Earth's core.

• The friction between two sliding plates.

What type of plate boundary occurs when two tectonic plates move towards each other?

• Divergent plate boundary

• Transform plate boundary

• Convergent plate boundary

• Subduction plate boundary

What happens at a transform plate boundary?

• Plates move towards each other.

• Plates move away from each other.

• Plates slide past each other in opposite directions.

• One plate sinks beneath another.