Natural Hazards Midterm 1

Front 1

Where has been hit with largest earthquake in the last 80 years

Back 1

Nepal (8.0)

Front 2

What is an earthquake

Back 2

Violent ground-shaking phenomenon by the suddenrelease of strain energy stored in rocks

Front 3

how many quakes a year

Back 3

1 million

Front 4

Where do quakes happen

Back 4

Most earthquakes concentrated along plateboundaries

Front 5

how can Earthquakes be compared (3 ways)

Back 5

1. magnitude (energy release)

2. intensity of shaking

3. resulting impact on people and society

Front 6

Old scale name

Back 6

Richter scale

Front 7

New scale

Back 7

Moment Magnitude Scale

Front 8

moment magnitude

Back 8

measurement of energy released by earthquake

Front 9

Richter magnitude

Back 9

the magnitude of local earthquakes as the log to the base of 10

Front 10

epicenter

Back 10

point on surface above focus

Front 11

Focus

Back 11

rapture on fault plane started

Front 12

Catastrophic earthquakes is a

Back 12

devastating event that destroys large cities and kills thousands

Front 13

Interplate earthquakes

Back 13

occur at or near boundary between twoplates

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Intraplate earthquakes

Back 14

Occur within plates

Front 15

what is a Fault

Back 15

fracture or fracture system along whichrocks have been displaced

Front 16

Slip Rate

Back 16

long-term rate of movement along a fault

Front 17

seismic waves

Back 17

shock waves produced by sudden rupture of the rocks

Front 18

active faults:

Back 18

faults active within last 10,000 years

Front 19

potentially active faults:

Back 19

displacement during Pleistocene time but not Holocene time

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inactive faults:

Back 20

not active in last 2 million years 4.

Front 21

paleoseismicity:

Back 21

determination of earthquake history along a fault, on basis of geologic record

Front 22

Tectonic creep

Back 22

1. gradual displacement not accompanied by felt earthquakes

2. produces slow damage of roads and structures 3. slow and continuous

Front 23

Four factors that determine shaking at some location

Back 23

1. magnitude

2. distance from the epicenter and focaldepth

3. local soil and rock conditions

4. direction of rupture

Front 24

3 Types of seismic waves

Back 24

1. P-waves

2. S-waves

3. surface waves (created by seismic waves reaching the Earth’s surface )

Front 25

the time between seismic waves

Back 25

Period

Front 26

the length from crest to crest of a wave

Back 26

.Wavelength

Front 27

the number peaks per second

Back 27

Frequency

Front 28

seismogram

Back 28

1. written or digital record of an earthquake

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depth of focus

Back 29

influences damage caused by earthquakes

Front 30

Stages of the earthquake cycle

Back 30

1. long period of seismic inactivity following amajor earthquake and associated aftershocks

2. period of increased seismicity as strainaccumulates

3. period of major foreshocks

4. major earthquake

Front 31

5 human activities are known to increase earthquake activity

Back 31

1.building a dam or reservoir

2. disposing of liquid through injection wells

3. underground nuclear explosions

4. pumping oil from the ground

5. hydraulic fracturing (fracking)

Front 32

What is Earth Science?

Back 32

studyand understand the planet Earth

Front 33

Scientific method:

Back 33

is a measure of discovering basic scientific principles

Front 34

Hypothesis:

Back 34

are formulated to explain the observations or data

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Theory:

Back 35

is a generally accepted explanation for a set of data or observations

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Law:

Back 36

is a generalization about the behavior of nature from which there has been no known deviation after numerous experiments

Front 37

Inception:

Back 37

4.6 billion years ago

Front 38

Internal forces within Earth

Back 38

Plate tectonics

Front 39

External forces on Earth’s surface

Back 39

Atmospheric effects

Front 40

Natural Processes

Back 40

Physical, chemical and biological waysby which events affect the Earth’ssurface

(Volcanoes– Rain– Erosion– Vegetation)

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Hazard

Back 41

natural process that poses a threatto human life or property

Front 42

Disaster

Back 42

the effect of a hazard on society,

event that occurs over a limited time span in a defined geographic area.

Front 43

Catastrophe

Back 43

a massive disaster

significant expenditure of time and money to recovery

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Annual loss of life

Back 44

150 000

Front 45

Financial loss

Back 45

20 bil

Front 46

when does a natural processes become hazardous

Back 46

when people live or workin areas where the processes occur

Front 47

Hazards most likely to produce catastrophe

Back 47

1. floods

2. hurricanes

3. tornadoes

4. earthquakes

5. volcanic eruptions

6. large wildfires

Front 48

Geologic Cycle

Back 48

Processes involving materials on or nearthe earth’s surface

Tectonic Cycle

Rock Cycle

Hydrologic Cycle

Biogeochemical Cycles

Front 49

Tectonic Cycle

Back 49

Refers to large-scale processes thatdeform Earth’s crust and producelandforms

Front 50

Rock Cycle

Back 50

recycling of three majorrock types

Front 51

Igneous rocks

Back 51

Form from crystallization of magma

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Sedimentary rocks –

Back 52

Rocks are weathered into sediment by wind and water

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Metamorphic rocks –

Back 53

Rocks are changed through extreme heat or, pressure

Front 54

Hydrologic Cycle (water cycle)

Back 54

evaporation,

precipitation,

surface runoff,

subsurface flow

Front 55

Biogeochemical Cycles

Back 55

The transfer or cycling of an element or elementsthrough the atmosphere

Front 56

The human response to hazards

Back 56

1. search and rescue

2. firefighting

3. providing emergency food, water, shelter

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Direct effects of disaster

Back 57

a. people killed, injured, displaced, or otherwise damaged

b. felt only by individuals immediately affected

Front 58

Indirect effects of disaster:

Back 58

a. emotional distress, donation of money or goods, paying taxes to finance recovery

b. felt by the general populace

Front 59

Stages of recovery

Back 59

a. emergency work

b. restoration of services and communication lines

c. reconstruction

Front 60

. Inner core

Back 60

Solid

1300 km in thickness

High temperature

Composed of iron

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Outer core

Back 61

Liquid

2000 km in thickness

Composition similar to the inner core

Front 62

Mantle

Back 62

Solid

3000 km in thickness

Composed of iron-rich and magnesium-rich silicate rocks

Front 63

Crust

Back 63

Outer rock layer of Earth

Mohorovicic discontinuity

Separates lighter crustal rocks from the more dense mantle

Front 64

Lithosphere

Back 64

cool, strong, outermost layer

average thickness is 100 km

crust is less dense than mantle rocks beneath

Front 65

Asthenosphere

Back 65

hot, slowly flowing layer of relatively weak rock

lies beneath lithosphere

Front 66

movement of Plate Tectonics

Back 66

Lithosphere is broken into plates, which moverelative to one another

Continental drift (pangea)

Front 67

Ocean-Continent Collision

Back 67

Continent volcanic arc of stratovolcanoes form from the heatingof the subducting plate and the melting of the overlying mantleand continental crust

Front 68

Ocean-Ocean Collision

Back 68

Oceanic island arc of basaltic volcanoes

Front 69

Rates of plate motion

Back 69

1-15 cm/yr

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What was Pangaea?

Back 70

supercontinent composed of all continents

Front 71

When did pangea split

Back 71

split 180 million years ago as modern continents began to move apart

Front 72

Divergent plate boundaries (Mid-Atlantic Ridge)exhibit

Back 72

earthquakes and volcanic eruptions

Front 73

Boundaries that slide past each other (San AndreasFault) have appreciable

Back 73

earthquake hazards

Front 74

Convergent plate boundaries where one plate sinks (subduction zones) contain explosive

Back 74

volcano and earthquake hazards

Front 75

Convergent plate boundaries where continentscollide (Himalayas) have

Back 75

high topography andearthquakes