Earthquakes and Seismic Waves

Front

What is a P wave?

Back

A type of seismic wave that compresses and expands the ground and is the first wave to arrive during an earthquake.

Front

What is the Mercalli scale?

Back

A scale that rates earthquakes according to their intensity and how much damage they cause at a particular place.

Front

What is the focus of an earthquake?

Back

The point beneath Earth's surface where rock breaks under stress and causes an earthquake.

Front

What are surface waves?

Back

Seismic waves that travel along the Earth's surface and produce more severe ground movements.

Front

What is the moment magnitude scale?

Back

A scale that rates earthquakes by estimating the total energy released by an earthquake.

Front

What is an S wave?

Back

A type of seismic wave that moves the ground up and down or side to side and arrives after P waves.

Front

What is an epicenter?

Back

The point on the Earth's surface directly above the focus of an earthquake.

Front

What is a seismograph?

Back

An instrument that measures and records details of earthquakes, such as force and duration.

Front

What is the Richter scale?

Back

A scale that measures the magnitude of earthquakes based on the amplitude of seismic waves.

Front

What causes earthquakes?

Back

Earthquakes are caused by the sudden release of energy in the Earth's crust, often due to tectonic plate movements.