Earthquakes - Chapter 12

Front

What are P waves?

Back

P waves, or primary waves, are seismic waves that arrive at the surface first. They move by compressing and expanding the ground like an accordion.

Front

What is a seismograph?

Back

A seismograph is an instrument that records the vibrations of the ground during an earthquake.

Front

What does a pen do in a seismograph?

Back

A pen is used to record the vibrations of the drum in a seismograph.

Front

What is the moment magnitude scale?

Back

The moment magnitude scale is a rating system that estimates the total energy released by an earthquake.

Front

What can cause damage after a large earthquake?

Back

An aftershock can cause damage days or months after a large earthquake.

Front

What are surface waves?

Back

Surface waves are seismic waves that travel along Earth’s surface and produce the most severe ground movements.

Front

What are S waves?

Back

S waves, or secondary waves, are seismic waves that arrive after P waves and move the ground up and down.

Front

What is the Richter scale?

Back

The Richter scale is a scale used to measure the magnitude of earthquakes, based on the amplitude of seismic waves.

Front

What is a tsunami?

Back

A tsunami is a series of ocean waves caused by large disturbances, such as underwater earthquakes.

Front

What is an earthquake?

Back

An earthquake is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere.