Earthquake Vocabulary

A break in the Earth's crust along which blocks of the crust slide relative to one another

• fault
• seismic waves
• aftershock
• liquefaction

A wave of energy that travels through the Earth, away from an earthquake in all directions

• fault
• seismic waves
• epicenter 
• focus

Known as primary or pressure waves

• P waves
• S waves

Known as secondary or shear waves

• P waves 
• S waves

A seismic wave that causes particles of rock to move in a back and forth direction

• S waves
• P waves
• surface waves
• seismic waves

A seismic wave that causes particles of rock to move in a side to side direction

• P waves 
• S waves
• surface waves
• seismic waves

These travel on Earth's surface and are slower and more destructive 

• fault waves
• focus waves
• surface waves
• seismic waves

An instrument that records vibrations in the ground and determines the location and strength of an earthquake

• seismograph
• epicenter
• aftershock
• Richter scale

The point on Earth's surface directly above an earthquake's starting point, or focus

• focus
• epicenter
• fault
• liquefaction

The point along a fault at which the first motion of an earthquake occurs

• focus
• epicenter
• surface
• fault