Geo Test 3

Front 1

force per unit area

Back 1

stress

Front 2

a change in size or shape in response to stress

Back 2

strain

Front 3

A stress due to a force pushing together on a body

Back 3

compressive stress

Front 4

A strss due to a force pulling away on a body

Back 4

tensional stress

Front 5

The behavior of an object that regains shape after stress is reduced or removed

Back 5

elastic behavior

Front 6

The behavior of an object that will bend while under stress and does not return to its original shape after sress is removed

Back 6

ductile behavior

Front 7

The behavior of an object that fractures at stresses higher than its elastic limit

Back 7

brittle behavior

Front 8

structures in which the beds dip away from a central point

Back 8

Structural Domes

Front 9

the compass direction of a line formed by the intersection of an inclined plane with a horizontal plane

Back 9

strike

Front 10

the direction and angle from horizontal in which a plane is oriented

Back 10

dip

Front 11

wavelike bends in layered rock

Back 11

folds

Front 12

upward-arching folds with oldest rocks in center

Back 12

anticline

Front 13

downward-arching folds with youngest rocks in its center

Back 13

synclines

Front 14

The surface trace of an axial plane

Back 14

hinge line

Front 15

folds in which the hinge line is not horizontal

Back 15

plunging fold

Front 16

structures in which the beds dip toward a central point

Back 16

Structural Basins

Front 17

have limbs that dip gently

Back 17

open fold

Front 18

have parallel limbs

Back 18

isoclinal folds

Front 19

have limbs that dip in the same directions

Back 19

Overturned folds

Front 20

have limbs that are overturned to the point of being horizontal

Back 20

recumbent folds

Front 21

fractures bedrock along which no movement has occurred

Back 21

Joints

Front 22

fractures in bedrock along which movement has occurred

Back 22

Faults

Front 23

have movement parallel to the dip of the fault plane

Back 23

Dip-slip faults

Front 24

have movement that is predominantly horizontal and parallel to the strike of the fault plane

Back 24

Strike-slip faults

Front 25

have movement with both vertical and horizontal components

Back 25

Oblique-slip faults

Front 26

The overlying surface of an inclined fault plane

Back 26

hanging wall

Front 27

The underlying surface of an inclined fault plane

Back 27

footwall

Front 28

A fault in which the hanging-wall block moved down relative to the footwall block.

Back 28

normal fault

Front 29

A downdropped block bounded by normal fault

Back 29

graben

Front 30

A up-raised block bounded by normal fault

Back 30

horst

Front 31

A fault in which the hanging-wall block moved up relative to the footwall block

Back 31

reverse fault

Front 32

A reverse fault in which the dip of the fault plane is at a low angle to horizontal

Back 32

thrust fault

Front 33

a trembling or shaking of the ground caused by the sudden release of energy stored in the rocks beneath

Back 33

earthquake

Front 34

Energy is released during earthquakes in the form of _____

Back 34

seismic waves

Front 35

the point of initial breakage and movement along a fault, where seismic waves originate

Back 35

focus

Front 36

point on Earth’s surface directly above the focus

Back 36

epicenter

Front 37

travel outward from the focus in all directions through Earth’s interior

Back 37

body waves

Front 38

travel along Earth’s surface away from the epicenter

Back 38

surface waves

Front 39

compressional (longitudinal) body wave in which rock vibrates back and forth parallel to the direction of wave propagation

Back 39

P wave

Front 40

shearing (transverse) body wave in which rock vibrates back and forth perpendicular to the direction of wave propagation

Back 40

S wave

Front 41

side-to-side motion of the ground surface

Back 41

Love waves

Front 42

ground to moves in an elliptical path opposite the direction of wave motion

Back 42

Rayleigh waves

Front 43

recording devices used to produce a permanent record of the motion detected by seismometers

Back 43

Seismographs

Front 44

permanent paper (or digital) records of the earthquake vibrations

Back 44

Seismograms

Front 45

Distance between the focus and the epicenter of an earthquake

Back 45

depth of focus

Front 46

a measure of the effects an earthquake produces (on both structures and people)

Back 46

Intensity

Front 47

more objective measure of energy released by a major earthquake

Back 47

Moment magnitude

Front 48

Scale expressing intensites of earthquakes

Back 48

modified Mercalli scale

Front 49

A numerical scale of earhquake magnitudes

Back 49

Richter scale

Front 50

occurs when water-saturated soil or sediment sloshes like a liquid during a quake

Back 50

Liquefaction

Front 51

Distinct earthquake zone that begins at an oceanic trench and slopes landward and downward into Earth at an angle of about 30 to 60

Back 51

Benioff zone

Front 52

the branch of geology that studies the interior of the Earth

Back 52

geophysics

Front 53

the return of some waves to the surface after bouncing off a rock layer boundary

Back 53

seismic reflection

Front 54

bending of seismic waves as they pass from one material to another having different seismic wave velocities

Back 54

seismic refraction

Front 55

the outer layer of rock that forms a thin skin on Earth’s surface

Back 55

crust

Front 56

a thick shell of dense rock that separates the crust above from the core below

Back 56

mantle

Front 57

the brittle outer shell of the Earth that makes up the tectonic plates

Back 57

lithosphere

Front 58

Zone where velocity decreases due to a molten rock

Back 58

asthenosphere

Front 59

Boundary that separates the crust from the mantle beneath it

Back 59

mohorovicic discontinuity

Front 60

Area where a hot core may melt lowermost mantle or react chemically to form iron silicates

Back 60

ultra low velocity zone

Front 61

equilibrium of adjacent blocks of brittle crust “floating” on upper mantle

Back 61

isostasy

Front 62

Rise of crust after ice sheet removal

Back 62

crustal rebound

Front 63

temperature increase with depth into the Earth

Back 63

geothermal gradient

Front 64

gently (0.1°) seaward-sloping shallow submarine platforms at the edges of continents

Back 64

continental shelf

Front 65

relatively steep slopes (typically 4-5°, but locally much steeper) that extend down from the edge of the continental shelf to the abyssal plain

Back 65

continental slope

Front 66

gently seaward-sloping (0.5°) wedges of sediments extending from base of continental slope to deep sea floor

Back 66

continental rise

Front 67

extremely flat regions beyond the base of the continental rise

Back 67

abyssal plain

Front 68

Conical undersea mountains that rise ≥1000 m above the seafloor

Back 68

seamounts

Front 69

Great fan-shaped deposits of sediment on the deep-sea floor

Back 69

abyssal fans

Front 70

Great masses of sediment-laden water that are pulled downhill by gravity

Back 70

turbidity currents

Front 71

a narrow, deep trough parallel to the edge of a continent or an island arc

Back 71

oceanic trench

Front 72

giant undersea mountain range extending around the world like the seams on a baseball

Back 72

mid-oceanic ridge

Front 73

flat-topped seamounts, apparently cut by wave action, and commonly capped with coral reefs

Back 73

guyots

Front 74

rock sequences in mountain chains on land that are thought to represent slivers of ocean crust and uppermost mantle

Back 74

ophiolites

Front 75

Where is the oldest layer of rock exposed in a structural dome?

Back 75

In the center

Front 76

Where is the youngest layer of rock exposed in a structural basin?

Back 76

In the center

Front 77

What is the Elastic rebound theory?

Back 77

That earthquakes are a sudden release of strain progressively stored in rocks that bend until they finally break and move along a fault

Front 78

April 18, 1906 – San Francisco Earthquake

Back 78

7.9 magnitude
42 seconds – strike slip rupture of over 280 miles

Front 79

October 17, 1989 – San Francisco, Oakland – Loma Prieta Earthquake

Back 79

6.9 magnitude
15 seconds – strike slip rupture did not break surface of Earth

Front 80

March 27, 1964 – Anchorage, southern Alaska Earthquake

Back 80

9.2 magnitude
240 seconds
area over 350,000 sq. miles
Mostly dip-slip movement

Front 81

January 17, 1995 – Kobe Japan Earthquake

Back 81

7.2 magnitude
20 seconds
Combination strike-slip and dip-slip movement

Front 82

January 17, 1994 – Northridge Earthquake – San Fernando Valley

Back 82

6.7 magnitude
15-30 seconds
Primarily dip-slip movement

Front 83

Which seismic waves CANNOT pass through liquid? (Hint: there are two kinds)

Back 83

S wave and Love waves

Front 84

What are the main hazards associated with earthquakes?

Back 84

Ground motion, fire, landslide, liquefaction,and tsunamis

Front 85

What is the evidence for a solid inner core and liquid outer core?

Back 85

The way in which P waves are refracted within Earth's core

Front 86

What is the equation for Newton’s law of gravitation

Back 86

Force=G((Mass A*Mass B)/Distance^2)

Front 87

G =

Back 87

6.67 x 10- 11 N m 2 /kg 2

Front 88

The Earth is gradually losing heat to space. What are the primary origins of the heat that is being lost?

Back 88

original heat (from accretion and compression as Earth formed) and radioactive decay

Front 89

How does sediment move from the continents to the abyssal plain?

Back 89

Submarine canyons

Front 90

land-derived sediments that have found their way to the sea floor

Back 90

Terrigenous sediments

Front 91

settle slowly through the ocean water, and are derived from fine-grained clay (delivered primarily by wind) and skeletons of microscopic organisms

Back 91

Pelagic sediments

Front 92

What is the age difference between oceanic and continental crust?

Back 92

All rocks and sediments of the deep sea floor are less than 200 million years old
-Continents preserve rocks up to 4 billion years old

Front 93

An episode of intence deformation of the rocks in a region, generally accompanied by metamorphism and plutonic activity

Back 93

orogeny

Front 94

flat, stable cores of the continents

Back 94

craton

Front 95

A complex of old Precambrian metamorphic and plutonic rocks exposed over a large area

Back 95

Precambrian shield

Front 96

A range created by uplift along normal or vertical faults

Back 96

fault-block mountain range

Front 97

The detachment of part of the mantle portion of lithosphere beneath a mountain belt

Back 97

delamination

Front 98

A region in which the geology is markedly different from that in the adjoining region

Back 98

tectonostratigraphic terranes or terranes (for short)

Front 99

A terrane that may mot have form at its present site

Back 99

suspect terranes

Front 100

Terrane that did not form at its present site on a continent

Back 100

accreted terrane

Front 101

(composed of many folds and reverse faults) indicate crustal shortening (and thickening) produced by compression

Back 101

fold and thrust belts