PLATE TECTONICS

Plate Tectonics

The theory that pieces of Earth's lithosphere are in constant motion, caused by convection currents in the mantle.

Convection Current

The transfer of heat through a liquid current changing temperatures.

Slab Pull

The force of gravity acting on the ocean crust, pulling it into the mantle.

Ridge Push

The force of magma pushing the tectonic plates apart.

Divergent Plate Boundary

Two tectonic plates that move in the opposite direction or away from each other.

Untitled Slide

Convergent Plate Boundary

Two tectonic plates that move together or towards each other. There are three types . . . .

Ocean and Ocean Crust

• Island arcs are formed.
• Ex: Alaskan Islands, Islands of Japan

CONTINENTAL AND CONTINENTAL CRUST

• Mountains are formed.
• Ex: The Himalayas

Ocean and Continental Crust

• Trenches are formed.
• Ex:Chile Peru deep sea trench

Subduction Zone

The process by which ocean floor is destroyed when sinking into the mantle.

Transform Plate Boundary

Two plates that slide past each other.

Deep Ocean Trench

A valley along the ocean floor at which the crust slowly sinks into the mantle. Ex: The Chile Peru trench