Geo 401 Lab Test 2

Front 1

Earthquake

Back 1

shaking motions and vibrations of the earth caused by large releases of energy that accompany volcanoes, explosions, and movements of Earth's bedrock along fault lines

Front 2

Focus

Back 2

the origin of an earthquake at depth in the earth

Front 3

epicenter

Back 3

the point on Earth's surface directly above the focus

Front 4

Seismic Waves

Back 4

elastic waves of vibration and shaking that originates at the focus of the earthquake and travel in all directions through, on, and below the surface of the Earth

Front 5

Seismograph

Back 5

record of seismic waves that is produced by a seismograph

Front 6

Body Waves

Back 6

seismic waves that travel through the earth's interior,

-P-waves: called primary waves because they travel fast and arrive at seismographs first; compression or "push-pull" waves
-S-waves: called secondary waves because they travel slower and arrive at seismographs second; perpendicular or "side-to-side" waves

Front 7

L-waves

Back 7

surface seismic waves that arrive at seismographs last because they travel along on earth's surface

Front 8

active faults

Back 8

faults that can move and generate earthquakes at the present time

Front 9

first motion

Back 9

the way the pen on a seismograph moves when the p-waves arrive can tell you about the relative motion of the fault zone
-compression: the pen moves up when the P-waves arrive
-dilation: the pen moves down when the P-waves arrive
-compression and dilation are relative motions

Front 10

topographic map

Back 10

two-dimensional model represent a three-dimensional landscape

Front 11

latitude

Back 11

measured from 0 at equator to 90 degrees N (at north pole) and 90 degrees S (at south pole)

Front 12

longitude

Back 12

measured east to west from 0 degrees at the prime meridian

Front 13

GPS (global positioning system)

Back 13

constellation of 28 satellites in 12 hour orbits about 12,000 miles above earth; based on the universal transverse mercator system.

Front 14

UTM (Universal Transverse Mercator System)

Back 14

global military navigation grid and coordinate system; grid is rectangular and measured in decimal-based metric units

Front 15

zones

Back 15

sixty north-south strips of longitude of a 6 degree width, numbered Zone 01 to Zone 60; location within a zone is defined by its easting and northing coordinate

Front 16

easting

Back 16

distance in meters within a zone measured from west to east

Front 17

northing

Back 17

distance in meters from the equator

Front 18

topographic profile

Back 18

cross section that shows the elevations, ruggedness, and slopes along a given line between two points

vertical exaggeration = vertical/horizontal scale

Front 19

relief

Back 19

difference in elevation between 2 points
regional relief: difference between the highest and lowest points on a topographic map

Front 20

gradient

Back 20

steepness of a slope; typically determined by dividing the relief between two points by the distance between them (including curves of streams)

Front 21

slope

Back 21

typically calculated as the change in elevation between to points divided by the straight-line distance between them (rise/run)

Front 22

declination

Back 22

difference in degrees of compass north and true north on a topographic map

Front 23

benchmark

Back 23

permanent marker placed by the U.S. geological survey or Bureau of Land management

Front 24

perennial streams

Back 24

flow continuously throughout the year and are represented by blue lines on topographic maps

Front 25

intermittent streams

Back 25

flow only at certain times a year, such as rainy seasons or during snow melt; they are represented by dotted line segments on a topographic map

Front 26

flood

Back 26

occurs when a stream overflows its banks

Front 27

alluvium

Back 27

sediment transported and deposited by streams

Front 28

stream drainage system

Back 28

drainage network including upland tributaries and main stream

Front 29

stream drainage patterns

Back 29

stream drainage systems form characteristic patterns of drainage depending on relief and geology. page 214 and fig 11.2 for specific patterns

Front 30

drainage basin

Back 30

entire area of land drained by one stream

Front 31

floodplain

Back 31

relatively flat areas on either side of a river prone to flooding

Front 32

cutbanks

Back 32

form at the outer edge of meanders and experience erosion

Front 33

point bars

Back 33

form at the inner edge of meanders and experience deposition

Front 34

oxbow lake

Back 34

forms as the result of a meander being cut off from main stream channel (due to flooding)

Front 35

stream terraces

Back 35

remnants of older floodplains

Front 36

submergent coastline

Back 36

created by a rising sea level; sea level rise can be caused by water level rising (transgression) or land level getting lower (subsidence)

Front 37

emergent coastline

Back 37

created by falling sea level; sea level can fall by water level falling (regression) or by rising of the land surface (uplift)

Front 38

barrier island

Back 38

long, narrow island that parallels the mainland coastline and is separated from the mainland by a lagoon, tidal flat, or salt marsh

Front 39

beach

Back 39

gently sloping deposit of sand or gravel along the edge of a shoreline

Front 40

estuary

Back 40

river valley flooded by a rise in level of an ocean or lake

Front 41

longshore current

Back 41

water current in the surf zone that flows slowly parallel to the shoreline, driven by waves; moves sediment in direction of current

Front 42

delta

Back 42

sediment deposit at the mouth of a river where it enters an ocean or lake

Front 43

spit

Back 43

sand bar extending from the end of a beach into the mouth of an adjacent bay

Front 44

wave-cut cliff

Back 44

seaward facing cliff along a steep shoreline, produced by wave erosion

Front 45

wave-cut platform

Back 45

bench or shelf at sea level along a steep shore, formed by wave erosion

Front 46

marine terrace

Back 46

eleveated platform that is bounded on its seaword side by a cliff or steep slope; formed when a wave-cut platform is elevated by uplift or regression

Front 47

stack

Back 47

isolated rocky island near a headland cliff

Front 48

sea wall

Back 48

an embankment of boulders, reinforced concrete, or other material constructed against a shoreline to prevent erosion by waves and currents

Front 49

groin

Back 49

short wall constructed perpendicular to shoreline in order to trap sand and make or build up a beach

Front 50

jetties

Back 50

long walls extending from the shore at the mouths of harbors and used to protect the harbor entrance from filling with sand or being eroded by waves and currents

Front 51

strike

Back 51

the compass bearing (direction) of a line formed by the intersection of a horizontal plane (such as the surface of a lake) and an inclined layer (bed, stratum) of rock,fault, fracture, or other surface.

Front 52

dip

Back 52

the angle between a horizontal plane and the inclined (tilted) stratum, fault, or fracture.

Front 53

faults

Back 53

breaks along which movement has occured. caused by tension compression and shear forces

Front 54

hanging wall

Back 54

top surface of a fault

Front 55

footwall

Back 55

the bottom surface of a fault

Front 56

normal fault

Back 56

tension fault, walls move away from one another

Front 57

reverse fault

Back 57

compression fault, walls move toward one another

Front 58

strike skip fault

Back 58

shearing fault, left lateral vs. right lateral means that from one side of the fault the other side appears to move in a certain direction, right for right lateral and vice versa

Front 59

anticlines

Back 59

oldest rocks in the middle

Front 60

synclines

Back 60

youngest rocks in the middle

Front 61

domes

Back 61

strata sloped upward, anticline

Front 62

basin

Back 62

strata slope downward like a bowl, syncline

Front 63

water table

Back 63

upper surface of the water logged zone called the zone of saturation

Front 64

groundwater

Back 64

water in the saturated zone

Front 65

well

Back 65

can withdraw groundwater

Front 66

aquifers

Back 66

rock strata that conduct water

Front 67

hydraulic gradient

Back 67

slope of the water table surface

Front 68

water table contour lines

Back 68

contour lines for water

Front 69

cone of depression

Back 69

change in the regional flow of groundwater around a well

Front 70

karst

Back 70

distinctive topography that indicates dissolution of underlying soluble rock, generally limestone

Front 71

sinkhole

Back 71

surface depression formed by the collapse of caves or other large underground void spaces

Front 72

artesian well

Back 72

water that wells out of the surface due to its own pressure somehow...a well that comes out at the surface of the earth on its own