Earth Science Exam 2

Front 1

Fractures

Back 1

Planes of weakness within the lithosphere

Two types: joints & faults

Front 2

Joints

Back 2

Fractures along which there has been no motion

Front 3

Faults

Back 3

-Fractures along which some motion has occurred

-Small-scale, local features that reflect the continental-scale motion going on at plate boundaries

Front 4

Normal faults

Back 4

-Reflect extensional motion

-Associated with divergent plate boundaries

Front 5

Reverse faults

Back 5

-Reflect contractional motion

-Associated with convergent boundaries

Front 6

Strike-slip faults

Back 6

Associated with transform plate boundaries

Front 7

Focus

Back 7

-Location on the fault where movement begins

-Located underground

-The source of vibrational waves that produce earthquakes

Front 8

Epicenter

Back 8

-Location on the surface of the Earth directly above the focus

-Can be pointed out on a map

Front 9

Body waves

Back 9

-Travel through Earth's interior

-Faster than surface waves

Front 10

Primary waves (P-waves)

Back 10

-Type of body wave

-Fastest seismic wave

-Compressional motion

Front 11

Shear waves (S-waves)

Back 11

-Type of body wave

-Second fastest seismic wave

-Vertical motion

Front 12

Surface waves

Back 12

-Travel along Earth's surface

-Slower than body waves

Front 13

Rayleigh waves (R-waves)

Back 13

-Type of surface wave

-Orbital motion

-Responsible for most damage

Front 14

Love waves (L-waves)

Back 14

-Type of surface wave

-Lateral (horizontal) motion

Front 15

Shaking of the ground

Back 15

-Earthquake hazard

-Seismic waves cause vibration of particles as they pass through material

Front 16

Aftershocks

Back 16

-Earthquake hazard

-Movement along main fault may initiate activation of nearby faults after first earthquake

Front 17

Landslides

Back 17

-Earthquake hazard

-Shaking can cause slopes to become unstable

-Can lead to serious problems with rescue, evacuation, and other relief efforts

Front 18

Changes in elevation

Back 18

-Earthquake hazard

-Movement along the fault can drop or raise the ground surface

-Ghost forests: coastal forests dropped down into salt water and killed

Front 19

Liquefaction

Back 19

-Earthquake hazard

-Shaking causes loose (un-cemented) sediment and soil to flow like a liquid

Front 20

Tsunami

Back 20

-Earthquake hazard

-Vertical movement along an underwater fault displaces all of the overlying water

Front 21

Magnitude

Back 21

-Amout if energy released during fault rupture

-Uses the Richter scale

Front 22

Intensity

Back 22

-Measure of the effects of earthquake on people and buildings

-Uses Modified Mercalli scale

Front 23

Volcanoes

Back 23

-Physical features produced through solidification of molten rock at the surface of the Earth

Front 24

Magma

Back 24

-Molten material within the Earth (below the surface)

-Mafic magma: contains little silica, similar to composition of the mantle, composition of oceanic crust

-Felsic magma: contains abundant silica, composition of continental crust

Front 25

Lava

Back 25

-Molten material on the surface of the Earth

Front 26

Caldera

Back 26

-Large depression generated by collapse of volcano following major eruption

-Emptying of magma within and underneath volcano leads to destabilization and collapse

Front 27

Shield volcano

Back 27

-Very large, broad, gently sloping features composed of solidified lava flows

Front 28

Composite volcano or stratovolcano

Back 28

-Moderatly steep-sided volcano composed of alternating layers of lava flows and pyroclastic material

Front 29

Cinder cone

Back 29

-Very small, steep-sided volcano composed entirely of pyroclastic material

Front 30

Vertical blast

Back 30

-Lava and gas ejected upwards

Front 31

Lateral blast

Back 31

-Volcanoes occasionally blow their sides off and direct the eruption sideways

Front 32

Tephra

Back 32

-Solid particles blasted into air by an eruption that rain down in surrounding areas

Front 33

Toxic gases

Back 33

-Volcanoes release a lot of sulfur and carbon dioxide

Front 34

Acid rain

Back 34

-Sulfur released by an eruption can generate local acid rain

Front 35

Pyroclastic flows

Back 35

-Mixture of hot volcanic gas and fine-grained solid material that flows rapidly down a volcano slope

Front 36

Lahars

Back 36

-Mudflows generated by mixing of melted snow and hot volcanic material

Front 37

Isostasy

Back 37

-Vertical movements of the Earth's lithosphere in response to the addition and removal of heavy loads

Front 38

Mass wasting

Back 38

-Downslope movement of solid material under the influence of gravity

Front 39

Creep

Back 39

-Very slow movement of material down a slope

-Particularly damaging to building foundations

-Common in areas where freezing and thawing occur

Front 40

Flow

Back 40

-General term for chaotic downslope motion of a mixture of rock, soil, and water

-Debris flow: dominated by water and coarse material

-Mudflow: dominated by water and fine material

Front 41

Slump

Back 41

-Unconsolidated solid material moves downslope along a curved surface

-Concave-upward surface

Front 42

Slide

Back 42

-General term for very rapid, large-scale downslope movement of solid material along an un-curved surface

-Rockslide: dominated by coherent rock

-Landslide: a mixture of soil, loose sediment, and rock

Front 43

Rockfall

Back 43

Solid, coherent blocks of rock fall through the air or roll down a cliff