Science Chapter 11 Vocab

Front 1

faults

Back 1

what rocks move along when they break

Front 2

elastic deformation

Back 2

applied forces cause rocks to undergo_______________

Front 3

elastic limits

Back 3

rock break when their _____________ are passed

Front 4

earthquake

Back 4

vibrations produced by breaking rock

Front 5

normal fault

Back 5

caused by rock above the fault moving downward in relation to the rock below the fault - tension forces

Front 6

reverse fault

Back 6

compression forces squeeze rock above the fault up and over the rock below the fault

Front 7

strike-slip

Back 7

fault created by shear forces; rocks on either side of the fault move past each other without much upward or downward motion

Front 8

seismic waves

Back 8

waves generated by an earthquake; can move the ground forward and backward and up and down and side to side

Front 9

focus

Back 9

an earthquake's point of energy release

Front 10

primary waves

Back 10

p-waves; cause particles to move back and forth in the same direction as the wave is traveling; move the fastest of the waves

Front 11

secondary waves

Back 11

s-waves; cause particles to move at right angles to the direction as the wave is traveling; move second fastest of the waves

Front 12

surface waves

Back 12

move rock particles in a backward rolling motion and sideways swaying motion; move slowest

Front 13

epicenter

Back 13

the point on Earth's surface directly above the earthquake focus

Front 14

seismograph

Back 14

measures seismic waves; consists of a rotating drum of paper and a pendulum with an attached pen

Front 15

seismogram

Back 15

the paper record of a seismic event

Front 16

crust

Back 16

Earth's outermost layer; about 5 to 60 km thick

Front 17

shadow zones

Back 17

do not receive seismic waves because the waves are bent or stopped by material of different density

Front 18

seismologists

Back 18

scientists who study earthquakes

Front 19

magnitude

Back 19

measure of energy released by an earthquake; determined by the Richter scale and based on the height of the lines on a seismogram

Front 20

Mercalli scale

Back 20

a modified intensity scale that describes earthquake intensity based on structural and geologic damage

Front 21

liquefaction

Back 21

shaking from an earthquake can make wet soil act like a liquid

Front 22

tsunamis

Back 22

ocean waves caused by earthquakes; caused when a sudden movement of the ocean floor pushes against the water; can travel thousands of km in all directions

Front 23

moorings

Back 23

made of alternating layers of rubber and steel; flexible; circular; placed under buildings to withstand seismic vibrations