Geo

Front 1

Angle of dip

Back 1

- a vertical angle measured downward from the horizontal plane to an inclined plane

Front 2

Anticline-

Back 2

fold shape line an arch in which the rock layer usually dip away from the axis of the fold and the of lest rock are in the center of the of the fold

Front 3

Axial plane

Back 3

- a plane containing all of the hinge lines of a fold

Front 4

Brittle-

Back 4

cracking under stress

Front 5

Direction of dip

Back 5

- the compass direction in which the angle of dip is measured

Front 6

Ductile-

Back 6

capable of being molded and bent under stress

Front 7

Elastic-

Back 7

the max amount of stress that can be applied to a body before it deforms in a way by bending or breaking

Front 8

Fault-

Back 8

a fracture in bedrock along which movement has taken place

Front 9

Fold-

Back 9

bend in layered bedrock

Front 10

Footwall-

Back 10

the underlying surface of an inclined fault plane

Front 11

Hanging wall

Back 11

- the overlying surface of an inclined plane

Front 12

Hinge line-

Back 12

line about which a fold appears to be hinged

Front 13

Joint-

Back 13

a fracture or crack in bedrock along which no displacement has occurred

Front 14

Joint set-

Back 14

joints oriented in one direction approximately parallel to one another

Front 15

Limb-

Back 15

portion of a fold shared by an anticline and a syncline

Front 16

Strain-

Back 16

change is size or shape of a body in response to stress

Front 17

Stress-

Back 17

a force acting on a body that tends to change the size or shape that body

Front 18

Strike-

Back 18

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

Front 19

Syncline-

Back 19

a tough-like fold in which the rock layers dip toward and axis.

Front 20

Source rock

Back 20

-a rock containing organic matter that is converted to petroleum by burial and other changes.

Front 21

Aftershock-

Back 21

small earthquake that follows a main one

Front 22

Body wave-

Back 22

seismic wave that travels through earth’s interior

Front 23

Earthquake-

Back 23

shaking of the ground caused by the sudden release of energy stored in the rocks beneath the surface

Front 24

focus-

Back 24

the point within an earth from which seismic waves originate in an earthquake

Front 25

Intensity-

Back 25

a measure of an earthquake size by its effect on people and buildings

Front 26

Island arc-

Back 26

a curve line of islands

Front 27

Love wave-

Back 27

a type of surface wave that caused the found to move side to side in a horizontal plane to the direction the wave is traveling

Front 28

Magnitude-

Back 28

the measure of energy during an earthquake

Front 29

P wave-

Back 29

a compressional wave in which rock vibrates parallel to the direction of wave propagation

Front 30

Seismic wave-

Back 30

the wave of energy released by an earthquake

Front 31

Seismogram-

Back 31

paper record of an earthquake

Front 32

Seismograph

Back 32

a seism there with a recording device that produces a record of earth’s motion

Front 33

Surface wave

Back 33

- a seismic wave that travels on earth’s surface

Front 34

S wave-

Back 34

wave propagated by a shearing motion, which causes rock to vibrate to the direction of wave propagation

Front 35

Travel-time curve

Back 35

- a plot of seismic wave arrival times against distance

Front 36

Tsunami-

Back 36

huge ocean wave produced by displacement of the sea floor

Front 37

Core-

Back 37

central zone of the earth

Front 38

Crust-

Back 38

the outer layer of a rock forming a thin skin over earth’s surface

Front 39

Crustal rebound-

Back 39

the rise of earth’s surface after the removal of glacial ice

Front 40

Curie point-

Back 40

the temp point in which a material becomes materialized

Front 41

Geophysics-

Back 41

the application of physical laws and principles to study of earth

Front 42

Gravity meter-

Back 42

an instrument that measures gravity attraction between earth and a mas within an instrument

Front 43

Heat flow-

Back 43

gradual loss of heat from earth interior out into space

Front 44

isostasy-

Back 44

the balance of equilibrium between adjacent blocks of crust resting on a plastic mantel

Front 45

Magnetic field-

Back 45

region of magnetic force that surrounds earth

Front 46

Magnetic pole-

Back 46

an area where the strength of the magnetic field is greatest and leaves earth surface

Front 47

Abyssal plains-

Back 47

flat regions usually found at the base of the continental rise

Front 48

Mantle-

Back 48

a thick shale of rock that separates earth’s crust above the core

Front 49

P wave shadow zone-

Back 49

103-142 away from earthquake’s epicenter, in which P waves from the earthquake are absent

Front 50

S wave shadow zone-

Back 50

more than 103 form an earthquake’s epicenter in which P waves are absent