APES Plate Tectonics

Plate Tectonics

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

Continental Drift

The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations

Pangea

(plate tectonics) a hypothetical continent including all the landmass of the earth prior to the Triassic period when it split into Laurasia and Gondwanaland

Fossils

Preserved remains of once-living organisms

Plate Boundaries

At plate boundaries, Earth's crust is broken (fault) and rocks slip past each other in one of 3 types of plate boundaries.

Divergent

A boundary where the plates are moving AWAY from each other.

Convergent

Plates collide, causing one plate to go underneath or both edges crumble, creating mountains

Transform

Plates that are moving past each other (rubbing next to each other) in opposite directions

Mantle

Earth's thickest layer made of hot rock and is less dense than the core, less hot, and has less pressure on it. It also has plasticity

Outer Core

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

Inner Core

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

Lithosphere

A rigid layer made up of the uppermost part of the mantle and the crust.

Athenosphere

The soft layer of the Mantle on which the tectonic plates move

Subduction Zone

A destructive plate margin where oceanic crust is being pushed down into the mantle beneath a second plate.

Sea-Floor Spreading

The process by which molten material adds new oceanic crust to the ocean floor

Hot Spots

An area where a column of hot material rises from deep within a planet's mantle and heats the lithosphere above it, often causing volcanic activity at the surface.

Convection Currents

Circular currents in the mantle caused by the magma being heated by the core off the Earth.