Geology Exam 2

Front 1

orogensis

Back 1

mountain building

Front 2

deformation

Back 2

change in material in rock shape, location change, and rotation

Front 3

stress

Back 3

force applied to surface per unit area

Front 4

force

Back 4

mass*acceleration

causes change in velocity

Front 5

confining pressure stress

Back 5

force equal in all directions

Front 6

differential stress

Back 6

differences in stress in different directions

Front 7

fluid pressure stress

Back 7

fluids internally pushing outward

Front 8

compression

Back 8

pushing greater in one direction

Front 9

tension

Back 9

pulled apart

Front 10

shear stress

Back 10

sliding

Front 11

fracture

Back 11

too much stress

Front 12

strain

Back 12

change in shape of material

Front 13

elongation

Back 13

caused my tension, type of strain

Front 14

contraction

Back 14

shortening, type of strain

Front 15

brittle deformation

Back 15

breaks in 2+ pieces

Front 16

ductile deformation

Back 16

changes shape without breaking (playdough)

Front 17

what determines rocks behavior?

Back 17

temperature, pressure, deformation rate & composition

Front 18

rocks at depth

Back 18

rocks flow, minerals may recrystallize

Front 19

shallow rocks

Back 19

rocks break, minerals uneffected

Front 20

joints

Back 20

crack/fracture

Front 21

fault

Back 21

sliding along crack

Front 22

fold

Back 22

rocks that's been bent

Front 23

veins

Back 23

any joint filled with minerals

Front 24

strike slip

Back 24

left lateral v. right lateral, moves side to side

Front 25

dip slip

Back 25

up/down along fault

Front 26

oblique slip

Back 26

diagonally to fault (both strike and dip slip)

Front 27

normal fault

Back 27

-hanging wall moves down with respect to footwall

-crust is thinner and longer

Front 28

reverse fault

Back 28

-hanging wall moves up

-results in shortening

Front 29

left lateral

Back 29

left side moves toward you

Front 30

right lateral

Back 30

right side moves toward you

Front 31

axial

Back 31

where curvature is greatest

Front 32

folds

Back 32

ductile deformation

Front 33

hinge zone

Back 33

the section of fold wit the tightest curvature

Front 34

limb

Back 34

planar/less curved area of fold

Front 35

anticline

Back 35

arch-like A shaped fold

Front 36

syncline

Back 36

U or V shaped fold

Front 37

monocline

Back 37

anticline & syncline together

Front 38

continental accretion

Back 38

-process of adding material

-occurs during subduction

-when erosion causes deposition of new sediments (adding to sides/widening)

Front 39

continental craton

Back 39

low density, floating masses

Front 40

Laurentia

Back 40

North America

Front 41

regional elevation

Back 41

adding material to thicken crust

Front 42

how to create mountains

Back 42

-magma=thickening crust

-heating=less dense rock=rising crust

Front 43

elevation decrease

Back 43

-faulting-> stretched/thin crust=float lower

-erosion

-cooling rocks=denser=sinks

Front 44

subduction to create mountain

Back 44

crust is thick by adding magma, by shortening, by accretion

Front 45

continental collision to create mountains

Back 45

one section is trying to subduct so one has high elevation- can't happen to crust is twice as thick

*biggest sections of accretion

Front 46

mantle upwelling to create mountains

Back 46

occurs at hotspots

ei: Hawaii, Yellowstone

Front 47

local elevation

Back 47

thrust faulting/normal faulting

folding- can create local mountains

Front 48

regional lows

Back 48

caused by extension of lithosphere

Front 49

continental extension

Back 49

faults creating lows

Front 50

rift basins

Back 50

normal fault

regional low elevation

Front 51

Grenville Orogeny

Back 51

oldest supercontinent called Rodinia

rifting, sedimentary rocks deposited passive margins develop

Front 52

Taconic Orogeny

Back 52

subduction of oceanic crust begins then island arc hits Lsurentia then sticks together

Front 53

Alleghanian Orogeny

Back 53

built Appalachian Mountains

Front 54

earthquakes

Back 54

-release of seismic energy

-breaking rocks

-fault rupturing and sliding

Front 55

hypocenter/focus

Back 55

exact center of earthquake

Front 56

epicenter

Back 56

center of earthquake located on the surface

Front 57

elastic rebound theory

Back 57

stress applied to an object transfers energy to it (snapping twig)

Front 58

strain

Back 58

as stress increases, strain increases

Front 59

P-waves

Back 59

primary waves

-fastest wave

-compresses

-bumping

Front 60

S-waves

Back 60

can't travel through liquid

perpendicular waves

Front 61

how are earthquakes recorded?

Back 61

seiemometers

Front 62

how to determine location of earthquake

Back 62

time difference between arrival of P and S waves

Front 63

how to determine size of earthquake

Back 63

measure amplitude of seismograph

Front 64

seismic refraction

Back 64

-earth becomes more dense as you go down in to earth so seismic velocity is faster

-waves are bent backward towards the surface

Front 65

liquefaction

Back 65

when soil loses all strength and begins to behave like a liquid

Front 66

relative time

Back 66

order of events

Front 67

absolute time

Back 67

the age of events

Front 68

Principle of Inclusions

Back 68

young sediment may contain old sediment

Front 69

Principle of Altered Contacts

Back 69

younger rocks can cause changes along their margins with older rocks

Front 70

unconformity

Back 70

any time there's gap in the rock record

Front 71

angular unconformity

Back 71

bedding is in a different orientation than original bedding

Front 72

nonconformity

Back 72

layered bedding on top of nonlayered

Front 73

disconformity

Back 73

layered rocks, gap, more layered rocks

Front 74

stromatolites

Back 74

longest living life forms

Front 75

stratographic correlation

Back 75

tracing layers from place to place

Front 76

lithologic correlation

Back 76

tracing rock layer based on fossil record

Front 77

chemical correlation

Back 77

tracing rock layer based on chemical composition

Front 78

time correlation

Back 78

tracing rock layers of the same age

Front 79

absolute time assumptions

Back 79

-rock composition hasn't been altered

-no daughters present when rock is formed

-isotopes are measurable

Front 80

decay equation

Back 80

(starting amount)*(1/2)^# half lives

Front 81

runoff

Back 81

movement of water on Earths surface

Front 82

overland flow

Back 82

streams, rivers and glaciers (all modes of transportation for water)

Front 83

drainage basin

Back 83

area where all water ends up in same place

Front 84

dendritic drainage

Back 84

many connected flows

Front 85

radial drainage

Back 85

central high point of elevation

Front 86

structurally controlled drainage

Back 86

based on underlying geology (most popular)

Front 87

volume

Back 87

width*height*velocity of water

plotted on hydrograph

Front 88

highest velocity is located in what part of a river?

Back 88

deepest

Front 89

sediment capacity

Back 89

-total amount of sediment river can transport

-based on speed of river

Front 90

what will impact discharge?

Back 90

shape of basin

Front 91

suspended load

Back 91

particles stuck, unable to move

Front 92

saltation

Back 92

bouncing sediments

Front 93

traction

Back 93

sediments roll and slide

Front 94

turbulent flow

Back 94

chaotic, curly, nonuniform lines

Front 95

laminar flow

Back 95

flowing straight lines

Front 96

eddy

Back 96

water curls as a result of turbulent flow

Front 97

meandering river

Back 97

low gradient, cohesive sediment, many curves

Front 98

braided river

Back 98

-network of interweaving channels

-fluctuating discharge, steep gradient, bed load

Front 99

fast river flow

Back 99

erosion

Front 100

slow river flow

Back 100

deposition

Front 101

average river flow

Back 101

transportation of sediment

Front 102

Thalweg

Back 102

fast section of a river with the least friction

Front 103

inner bank

Back 103

point bar lots of deposition in this part of a river

Front 104

outer bank

Back 104

cutbank, steep side of a river

Front 105

floodplain

Back 105

define channels over years

Front 106

levees

Back 106

coarse grains deposited which create raised embankment

Front 107

base level

Back 107

lowest level to which a river can erode

Front 108

how are deltas created

Back 108

rapid water flow hitting flat land

Front 109

rules of erosion/deposition

Back 109

river discharge: increase=stream erodes

decrease=stream deposits

sediment supply: increase=stream deposits

decrease=stream erodes

Front 110

stream incision

Back 110

occurs when land elevation changes quickly in relation to elevation of river

Front 111

what effects shorelines?

Back 111

storms, rock type, orientation of coastline, and the slope of the seafloor

Front 112

tides

Back 112

-cyclic changes in height of sea surface

-water is being pulled by gravitational force of moon

-tides change as earth rotates

Front 113

spring tides

Back 113

moon and sun align once s month to create the biggest tides

Front 114

neap tides

Back 114

sun and moon are perpendicular to each other

Front 115

waves

Back 115

-water molecules moving in circular patterns

-deeper water has less motion

Front 116

how do waves form?

Back 116

-wind blows, flowing air collides with water

-height increases and wavelength decreases through travel

-waves break where wave base is equal to or exceeds water depth

Front 117

how waves break

Back 117

-friction between bottom of wave and ocean floor, so wave slows down and begins to lean forward then waves can't move in circular motion anymore so they break

Front 118

when waves hit shoreline

Back 118

-swirl away loose pieces of bedrock

-waves bend (refract) if they approach the shore at an angle

Front 119

swash

Back 119

forward movement of wave-- stronger than backwash

Front 120

backwash

Back 120

backward movement of wave

Front 121

waves deposit

Back 121

-gentle gradients along beach

-lots of available sediment

-rising sediment

Front 122

waves erode

Back 122

-steep/absent beach

-little available sediment

-rising sea level

Front 123

how to prevent waves

Back 123

sea wall and rip rap, breakwater, beach nourishment, or jetties