Chapter 12

Question 1

movement or trembling of the ground that is caused by a sudden release of energy when rocks along a fault move

Answer 1

earthquake

Question 2

the sudden return of elastically deformed rock to its undeformed shape

Answer 2

elastic rebound

Question 3

location along the fault at which the first motion of an earthquake occurs

Answer 3

focus

Question 4

90% of continental earthquakes; most damaging earthquake

Answer 4

shallow foci

Question 5

shallow foci

Answer 5

0-70 km

Question 6

intermediate foci

Answer 6

70-300 km

Question 7

deep foci

Answer 7

300-650 km

Question 8

usually by subduction zones

Answer 8

deep foci

Question 9

the point on the Earth’s surface directly above the focus

Answer 9

epicenter

Question 10

vibrations produced as energy is released by rocks as they slip into a new position

Answer 10

seismic waves

Question 11

waves that travel through the body of a medium

Answer 11

body waves

Question 12

waves that travel along the surface of a body rather than through the middle

Answer 12

surface waves

Question 13

fastest waves

Answer 13

P waves

Question 14

body waves that can travel through solids, liquids or gasses

Answer 14

P waves

Question 15

second fastest waves

Answer 15

S waves

Question 16

body waves that can only travel through solids

Answer 16

S waves

Question 17

primary/ compression waves

Answer 17

P waves

Question 18

secondary/ shear waves

Answer 18

S waves

Question 19

waves that cause the most damage

Answer 19

surface waves

Question 20

form from the conversion of energy when P and S waves reach Earth’s surface

Answer 20

surface waves

Question 21

slowest-moving waves

Answer 21

surface waves

Question 22

cause rocks to move side to side and perpendicular to the direction in which the waves are traveling

Answer 22

love waves

Question 23

cause rooks to move in an elliptical, rolling motion

Answer 23

rayleigh waves

Question 24

___ was a ___ scientist who discovered the boundary between the crust and the mantle in ___.

Answer 24

Andrija Mohorovicic
Croatian
1909

Question 25

What are the three compositional layers of the Earth? (from outside to inside)

Answer 25

crust, mantle, core

Question 26

What are the five mechanical layers of the Earth? (from outside to inside)

Answer 26

lithosphere, asthenosphere, mesosphere, outer core, inner core

Question 27

locations on Earth's surface where no body waves from a particular earthquake can be detected

Answer 27

shadow zones

Question 28

___ waves can't travel through Earth's ___ which creates shadow zones.

Answer 28

S | liquid outer core

Question 29

earthquakes occur as the overriding plate scrapes against the top of the subvergent plate (tectonic plate environment)

Answer 29

convergent oceanic environments

Question 30

spreading motion at the mid-ocean ridge causes earthquakes (tectonic plate environment)

Answer 30

divergent oceanic environments

Question 31

as ___ plates converge, diverge, or slide past each other horizontally rocks undergo stress; stress causes mountains to form and earthquakes to occur (tectonic plate environment)

Answer 31

continental | continental environments

Question 32

regions of numerous, closely spaced faults

Answer 32

fault zones

Question 33

the study of earthquakes

Answer 33

seismology

Question 34

one who studies earthquakes

Answer 34

seismologist

Question 35

instrument that detects and records vibrations in the ground

Answer 35

seismograph

Question 36

tracing of earthquake motion that is recorded by an instrument

Answer 36

seismogram

Question 37

How do scientists determine the location of the epicenter?

Answer 37

they triangulate the epicenter with at least three seismograph stations

Question 38

measure of the strength of an earthquake

Answer 38

magnitude

Question 39

measures magnitude based on ground motion

Answer 39

Richter scale

Question 40

measures magnitude; preferred by scientists

Answer 40

moment magnitude scale

Question 41

What does the moment magnitude scale base its measurements on?

Answer 41

strength, size of the area of the fault that moves, average distance fault block moves, rigidity of the rocks in the fault zone

Question 42

the measure of the amount of damage caused by an earthquake

Answer 42

intensity

Question 43

What measures intensity? How?

Answer 43

Modified Mercalli scale | with Roman numerals I-XII

Question 44

What is the number one cause of injuries in earthquakes?

Answer 44

the collapse of buildings and other structures

Question 45

giant ocean wave formed after a volcanic eruption, submarine earthquake, or submarine landslide

Answer 45

tsunamis

Question 46

What is the most important thing to do ruing an earthquake?

Answer 46

stay calm

Question 47

How do scientists predict earthquakes?

Answer 47

currently there is no reliable way of predicting exactly when and where earthquakes will occur

Question 48

an area along a fault where relatively few earthquakes have occurred recently but where strong earthquakes occurred in the past

Answer 48

seismic gap

Question 49

little earthquakes that precede earthquakes by a few seconds or weeks

Answer 49

foreshocks

Question 50

Scientists attempt to predict earthquakes by changes in rock such as ___. Sometimes ___ can indicate earthquakes.

Answer 50

tilting of rock, magnetic & electrical changes in rock detected by water put in cracks natural gas seepage