Plates Vocab

Front

What is seafloor spreading?

Back

The formation of new ocean crust as a result of magma pushing upward and outward from Earth's mantle to the surface.

Front

What is a mid-ocean ridge?

Back

An underwater mountain chain where new ocean floor is formed.

Front

What is a rift valley?

Back

A valley formed by the separation of tectonic plates.

Front

What occurs at a divergent plate boundary?

Back

Where two plates are moving apart, magma comes up to create new crust.

Front

What is a transform plate boundary?

Back

Boundary between two plates that are sliding past each other.

Front

What is continental drift?

Back

The theory that continents have moved over geological time and were once joined together.

Front

What is the lithosphere?

Back

The rigid outer layer of the Earth, consisting of the crust and upper mantle.

Front

What is the asthenosphere?

Back

The semi-fluid layer of the mantle beneath the lithosphere that allows tectonic plates to move.

Front

What is subduction?

Back

The process where one tectonic plate moves under another and sinks into the mantle.

Front

What is plate tectonics?

Back

The scientific theory that describes the large-scale movements of Earth's lithosphere.