# Chapter 6-Earthquakes Study Guide

## 8 terms

### Know what kind of stress that causes earthquakes, their movement, and the type of faults they produce

1. Tension--Diverge---Normal
2. Compressional--Converge--Reverse
3. Shearing--Slip past each other--Strike--Slip

### Know what anticlines and synclines are

Anticline- A fold in rock that bends upward into an arch
Syncline- A fold in rock that bends downward to form a valley

### Know the three scales used to measure earthquake damage, what each measures, and the scale they use

Richter--Magnitude
Mercalli--Earthquake's level of damage
Moment Magnitude--Estimates total energy released

### Know the three types of energy waves released by an earthquake

P Wave-- 1st-- Compress and Expand
S Wave-- 2nd-- Side to Side
Surface Wave-- 3rd-- Up and down; Side to side

### What are safety measures one can take if indoors when an earthquake strikes?

1.Drop, cover, hold
2. Crouch against an inner wall
3. Crouch beneath a desk or table and hold on
4. Move away from windows, doors, hanging objects, loose objects

### Know how scientists find the epicenter of an earthquake using triangualtion. Include differences in arrival times of waves and distances from epicenter in your explanation.

Scientists use seismic waves to locate an earthquakes epicenter by which waves come at different times, p waves, s waves, surface waves

### Know the 4 instruments geoglists use to measure movements along faults and how each one works

Tiltmeters- Measures vertical movement
Creep Meters- Measures movement
Laser-Ranging device- Measures horizontal movement
GPS Satellite- Measures changes in elevation and tilt of land along with horizontal movement

### Why is it hard to predict earthquakes?

We do not have enough data and equipment to determine when may earthquakes come