Earthquake Study Guide

What force is used to push something together causing it to be squashed or compacted?

Compression Force

What type of focus is located deep in the earth's crust in the subduction zone and appears along fault lines?

Deep Focus

What is the measurement of how steeply the fault plane slopes?

Dip

What type of fault is both a normal and reverse together because the movement on the occurs along the dip direction either down or up?

Dip-Slip Fault

What are horizontal surface waves that cause particles to move side to side?

L-Waves

What are unconsolidated materials that are water saturated may turn to a fluid causing some underground objects such as storage tanks to float to the surface?

Liquefaction

What is a measure of the strength or amount of energy released during an earthquake?

Magnitude

What is the largest of the shocks in a sequence of earthquakes?

Main Shock

What type of fault forms when the hanging wall drops down relative to the footwall?

Normal Faults

What is a seismic body wave that shakes the ground back and forth in the same travel direction?

P-Waves

What type of fault forms as a result of hanging wall moving up compressing rocks together?

Reverse Faults

What is a numerical rating system used to measure the amount of energy released during an earthquake?

Richter Scale

What are seismic body waves where particles move at a right angle to the direction of the wave?

S-Waves

What is a rhythmic sloshing of small bodies of water?

Seiche

What is a paper record produced by a seismograph that records seismic waves?

Seismogram

What is an instrument used to record earthquake waves?

Seismograph

What type of focus is located 44 miles or less down and is caused by fault movement or continental plates?

Shallow Focus

What is a system of force that operates against a body from different sides?

Shear Force

What type of fault has walls that move sideways and are usually horizontal so they do not have a hanging wall or footwall?

Strike Slip Fault

What is the force that causes stretching or pulling of plates so there is a buildup of energy until it is released?

Tension Force

What is a seismic sea wave that is sometimes generated when an earthquake originates on the ocean floor?

Tsunami

What are series of tremors that help with adjustments in the crust after the earthquake?

After Shock

What are vibrations or seismic waves within earth materials that are produced by the rapid release of energy?

Earthquakes

What type of energy does the earth's crust store that causes earthquakes?

Elastic Energy

What is the place on the surface directly about the focus called?

Epicenter

What is a large crack in the Earth's crust where one part of the crust has moved against another part?

Fault

What is the surface trace of fault, the intersection between the fault plane and the Earth's surface?

Fault Line

What is the actual place underground where the rocks break producing vibrations?

Focus

What is an earthquake that occurs before a larger seismic event and is related to it in both time and space?

Foreshocks

What is the measurement of the effects on an earthquake at a particular location?

Intensity