Chapter 8 Vocab

The innermost zone of Earth’s interior, composed mostly of iron and nickel. It includes a liquid outer layer and a solid inner layer.

The layer of Earth above the core, containing magma.

Molten rock.

The layer of Earth located in the outer part of the mantle, composed of semi-molten rock.

The outermost layer of Earth, including the mantle and crust.

In geology, the chemically distinct outermost layer of the lithosphere.

In geology, a place where molten material from Earth’s mantle reaches the lithosphere.

The theory that the lithosphere of Earth is divided into plates, most of which are in constant motion.

The process of one crustal plate passing under another.

A vent in the surface of Earth that emits ash, gases, or molten lava.

An area beneath the ocean where tectonic plates move away from each other.

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

An area where plates move toward one another and collide.

An area where tectonic plates move sideways past each other.

A fracture in rock caused by a movement of Earth’s crust.

The frequency and intensity of earthquakes experienced over time.

A large expanse of rock where a fault has occurred.

The sudden movement of Earth’s crust caused by a release of potential energy along a geologic fault and usually causing a vibration or trembling at Earth’s surface.

The exact point on the surface of Earth directly above the location where rock ruptures during an earthquake.

A scale that measures the largest ground movement that occurs during an earthquake.

A series of waves in the ocean caused by seismic activity or an undersea volcano.

Igneous rock that forms when magma rises up and cools in a place underground.

Rock that forms when magma cools above the surface of Earth.

In geology, a crack that occurs in rock as it cools.