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Lesson Flashcards: Earthquakes Geology

Earthquake focus

The point within the subsurface from which an earthquake originates

Earthquake epicenter

The point on Earth’s surface directly above an earthquake focus

Plutonic earthquake

An earthquake that has a focus exceeding 300 km in depth

Seismic wave

A wave of energy that travels through Earth as a result of an earthquake or other sources


The vibrations resulting from a release of energy in the rocks of the crust and upper mantle

Volcanic earthquake

An earthquake that is a result of volcanic activity, such as magma moving in the subsurface or volcanic eruptions

Primary wave

A seismic body wave that is compressional and pushes rocks back and forth within the ground

Secondary wave

A seismic body wave that is transverse and pushes rocks up and down within the ground

Earthquake magnitude

The measure of the total amount of energy released by an earthquake

Surface wave

A seismic wave that travels along the upper layers of Earth’s crust

Earthquake intensity

The measure of surface damage caused by an earthquake

Tectonic earthquake

An earthquake that is caused by the sudden movement along plate-tectonic boundaries and faults

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