Geology

Front 1

this states that the older strata or sedimentary layers are at the bottom in a series and the younger layers are at the top

Back 1

Principle of Superposition

Front 2

rock layers are laid down in an essentially horizontal manner.

Back 2

Principle of Horizontality

Front 3

sediments extend laterally in all directionsuntil they extended to the edges of the basin in which they are deposited

Back 3

Principle of Lateral Continuity

Front 4

states that an igneous intrusion or fault mustbe younger than the rocks it intrudes or displaces

Back 4

Principle of cross-cutting relationships

Front 5

states that the fragments or inclusions of onerock contained in another rock layer are older than the rock layer itself

Back 5

Principle of Inclusion

Front 6

a surface of nondeposition or erosion that separatesyounger strata from older rocks. It represents a break in our record ofgeologic time.

Back 6

Unconformities

Front 7

a surface of erosion or non-deposition betweenyounger and older beds that are parallel to one another. ,4*�_v��

Back 7

Disconformities

Front 8

an erosional surface on tilted or folded strataover which younger strata have been deposited. nt4*�_u��

Back 8

Angulare unconformities

Front 9

an erosional surface cut into a metamorphic origneous rock layer and overlaid by younger sedimentary rock strata. oung*ic

Back 9

Non-Conformity

Front 10

rock layers are squeezed

Back 10

Compressional Stress

Front 11

forces acting in opposite directions.

Back 11

Tension

Front 12

lengthening the rock layer and ultimatelypulling it apart

Back 12

Shear Stress

Front 13

rocks are stressed and deformed but return backto their original shape

Back 13

Elastic

Front 14

rocks are stressed past their elastic limit andremain in their new deformed shape

Back 14

Plastic

Front 15

the direction of a line formed by theintersections of a horizontal plane and an incline plane

Back 15

Strike

Front 16

A measure of the maximum angular deviation of anincline plane with the horizontal. It is measured perpendicular to the strike

Back 16

Dip

Front 17

A fault in which the hanging wall has moved downrelative to the foot wall.

Back 17

normal fault

Front 18

a fault in which the hanging wall has moved uprelative to the foot wall

Back 18

Reverse Fault

Front 19

fault where the hanging wall is bounded by twofoot walls, one on either side of the hanging wall block. The hanging wall hasmoved down relative to the two foot walls

Back 19

Graben Fault

Front 20

Fault where the foot wall is bound by twohanging wall, one on either side of the footwall. The footwall is moved uprelative to the two hanging walls

Back 20

Horst Fault

Front 21

a bend or a flexure in an otherwise horizontalor uniformly dipping rock layers

Back 21

Fold

Front 22

a fold where the rock layers are arched upward

Back 22

Anticlyne

Front 23

Downward folded rock layer

Back 23

Syncline

Front 24

A plane that cuts the fold in half

Back 24

axial plane

Front 25

One half of a fold (created by the axial plane)

Back 25

Limb

Front 26

A line formed by the intersection of axial planeand the folded layers

Back 26

fold axis

Front 27

the axial plane is vertical and each limb dipsat the same angletr!y

Back 27

symmetric fold

Front 28

the axial plane is incline and the limbs dip atdifferent angles?_ �?y�i

Back 28

Asymmetric fold

Front 29

a fold where the fold axis is inclined to thesurrounding layers, so it appears to be plunging into the surrounding rocklayers

Back 29

Plunging fold

Front 30

a type of asymmetric fold in which axial planeis horizontal

Back 30

Recumbent fold

Front 31

vibration of the earth caused by a suddenrelease of energy, usually as a result of faulting, which involves thedisplacement of rocks along fractures

Back 31

Earthquake

Front 32

rocks on either side of a fault where motion istaking place, will bend or become deformed. When the rocks reach their breakingpoint, they break and snap back to their original deformed shape, releasingenergy in the process. ��W

Back 32

elastic rebound theory

Front 33

the instrument that detects, records andmeasures the various vibrations produced by a earthquake. tures.R �2v�i

Back 33

seismagraph

Front 34

the record made by a seismograph

Back 34

seismogram

Front 35

the location within the earths crust wheremotion or rupture takes place and energy is first released. W

Back 35

Focus

Front 36

the point on the earths surface locatedvertically above the focus-EndFra^ �>z�i

Back 36

Epicenter

Front 37

waves produced by earthquakes are either bodywaves or surface wavesndFra^ �>z�i

Back 37

Seismic Waves

Front 38

primary waves the fastest seismic waves and cantravel through solids liquids and gasses. This type of wave is a compressionalwave

Back 38

p-waves

Front 39

secondary waves that can only travel throughsolidse of wX �8x�i

Back 39

s-waves

Front 40

slower of the two surface waves. These behavelike a water wave in which particles move in an elliptical pattern along avertical plane perpendicular to the direction of the motion of the wave] �=I�

Back 40

R-waves

Front 41

similar to the motion of an s-wave but the particlesof the material move back and forth along a horizontal plane perpendicular tothe direction of wave travelFY �9M�

Back 41

L-waves

Front 42

a qualitative subject measurement of theearthquake based on the amount and kind of damage buildings and surroundinggeologic structure-D �$r�

Back 42

Intensity

Front 43

a qualitative comparison of the amount of energyreleased by an earthquake at its source. It is an open ended scale beginning with1. It is a base -10 logarithmic scale used to compare the amplitude of EQ’s.each whole number EQ has 10 fold the amount of energy than the previous whole numberon the scale. S!2X

Back 43

Magnitude