Chapter 19-Earthquakes Flashcards
1
Q
Stress
A
Forces per unit area that act on a material
2
Q
Strain
A
Deformation of materials in response to stress
3
Q
Fault
A
Fracture or system of of fractures in earth’s crust
4
Q
Primary wave
A
Seismic wave that squeezes and pulls rocks in the same direction that the wave travels
5
Q
Secondary wave
A
Seismic wave that causes rock particles to move at right angles
6
Q
Surface wave
A
Seismic wave that moves in two directions as it passes through rocks
7
Q
Focus
A
Point of the initial fault rapture where an earthquake originates
8
Q
Epicenter
A
Point in earth’s surface directly above the focus of an earthquake
9
Q
Seismometer
A
Instrument used to measure horizontal or vertical motion during an earthquake
10
Q
Magnitude
A
Measure of the energy released during an earthquake (Richter scale)
