Mantle Convection

What happens to magma that is heated up at the core?

• It falls
• It rises

What characteristic of the asthenosphere helps explain the evidence of crustal-plate motion?

• the magnetic properties
• the semiliquid physical state
• the ability to deflect solar winds
• the ability to absorb heat energy

Which of the following changes would end Earth's tectonic activity?

• Earth's crust becomes a cooler solid
• Earth's mantles becomes a warmer semiliquid
• Earth's mantle becomes cooler and solid.
• Earth's outer core becomes warmer

The diagram represents the movement of the mantle under the earth's crust. Which process is represented by the diagram?

• rotation
• conduction
• radiation
• convection

Convection currents in the mantle are thought to be the driving force behind tectonic movement. At which location do the convection currents cause the plates to diverge?

• strike-slip fault
• subduction zone
• mid oceanic ridges
• folded mountains.

The diagram shows a rift valley formed by the movement of tectonic plates.Which movement of tectonic plates caused the rift valley to form?

• Two tectonic plates separated from each other.
• Two tectonic plates collided with each other.
• One tectonic plate slid under another.
• One tectonic plate slid past another.

The diagram shows what can occur when two continental plates collide.Which characteristic of the Indian Plate explains why it moves under the Eurasian Plate?

• It is larger.
• It is denser.
• It is molten.
• It is younger.

Along the west coast of South America, volcanic mountains are found due to movement along a plate boundary. The diagram illustrates the movement that is taking place.Which is the most likely reason for the formation of the volcanic mountains?

• The volcanic arc is sliding from the continental crust into the trench.
• A fault line, created by the sinking lithosphere, is filling with water.
• Oceanic crust collides with continental crust, heating as it subducts.
• As a result of an earthquake, multiple volcanic arcs are appearing.