Plate Tectonics Study Set: Key Terms & Definitions

Continental Drift

Theory that the continents are in constant motion on the surface of the Earth

Pangaea

Supercontinent containing all the continents.

Glaciers

Huge, slow moving sheets of ice that carved grooves in the ground leaving a fossilized path of evidence

Mid-Ocean ridges

Mountain ranges in the middle of the ocean.

Earth's magnetic field

forces created by convection currents within the Earth's outer core.

Causes a compass to work

Sea floor spreading theory

Process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge.

convection current

Heat transfers in a circular cell when molten material rises and cooler materials sink.

Plate Tectonics

A theory that states that Earth's surface is made of rigid slabs of rock or plates that move with respect to each other.

Divergent Plate Boundary

Two plates separate moving away from each other

Convergent Plate Boundary

Two plates moving towards each other

Transform Plate Boundary

Two plates slide past each other.

Subduction

The process of sinking of the denser plate below a more buoyant plate.

Fault

A break in the Earth's crust, smaller than a plate boundary, where one block of rock moves toward, away from or past another.

Hotspot

An area where magma from deep within the mantle melts through a thin area of the crust in the middle of a tectonic plate

Earth's crust

Outermost layer of our planet made up of continental and oceanic sections

Earth's Mantle

Between the core and the crust, about 2,900 km thick and nearly 80% of Earth's total volume

Inner Core

A dense sphere of solid iron and nickel at the center of Earth

Outer Core

A layer of molten iron and nickel that surrounds the inner core of Earth

Oceanic Crust

thinner, more dense, younger crust

Continental Crust

Thicker, less dense, older crust

Hawaiian Islands

Tropical vacation spot created by Geologic Hotspot beneath Pacific Ocean Plate