Hazards

how different people see the threat of a hazard

high stress to avoid 3Fs

technological solution- 3Ps

freeze, flight, fight

Predict, protect, prepare

modify risk, modify vulnerability, modify loss

relief, rehabilitation, reconstruction

geophysical, atmospherical, hydrological

hazards caused by land processes, majorly tectonic plates

hazards caused by atmospheric processes and the conditions created becauses of theses such as westher systems

hazards cause by water bodies and movement

a hazard that seriously effects humans

10 or more died, 100 or more effected

where and who

when and length of time

mitigation, preparedness, response, recovery

illustrates the ongoing response to a disaster, shows pre disaster and post disaster

government to reduce the impacts of a disaster

primordial, radiogenic

gravity

heat left from earths formation

heat left from radioactive decay of isotopes

plates move apart

plates move together

plates slide past eachother

1991

pre-disaster, event, relief, rehabilitation, recovery and reconstruction

isolation, population density, distance, timing

predictability, duration, magnitude, frequency

volcanoes

wildfires

floods

if a population isn’t vulnerable the hazards wont have a significant effect thus it won’t be disastrous

shaking of the ground

80%

5%

over 150,000

strike slip faults, normal dip slip faults, thrust faults

crustal blocks sliding past eachother

tension in crustal rocks- pulling apart

compression in the crust- collision

body, surface

primary waves, secondary waves

love waves, raleigh waves

compressional longitudinal waves, fastest waves, can travel through solids and liquids

transverse waves, slower waves, can only travel through solids, cause lots of damage

travel through crust, cause most damage, slower than body waves

cause ground to move sideways

cause ground to move up and down- rolling movement

richter scale, moment magnitude scale, modified mercalli intensity (MMI)

a logarithmic scale of 1 to 10 formerly used to express the magnitude of an earthquake on the basis of the size of seismograph oscillations

qualitative scale based on observation on how much damage is caused by an earthquake, scale of 1-12

a logarithmic scale of 1 to 10 that enables seismologists to compare the energy released by different earthquakes on the basis of the area of the geological fault that ruptured in the quake

monitoring groundwater levels, radon gas, animal behaviour, fault line monitoring

fault lubrication, reflecting waves by drilling boreholes

Valdiva (Chile)= 1960= 9.5MMS

visible breaking and displacement of earths surface

soil with high water concentration act like a fluid

giant sea waves generated by shallow focus underwater earthquake's

slope failures due to an earthquake

2011

9.0

16,000

over 800 were above a magnitude of 4.5

directly caused by the event

caused by other processes

solid material of varying size ejected into the atmosphere by a volcano

very hot gas charged high velocity flows of tephra and gas down a volcano

700 km/hour

over 800 degrees

co2, co3, h2s, so2, cl2

1986, co2 emissions from lake in the crater of Nyos in cameroon killed 1700 people

low velocity flow of lava than is often unstopped so damages crops and building. rarely injures people

10 km/hour

lava flows, tephra, pyroclastic flows, volcanic gas

unconsolidated ash from a recent eruption combines with water is swept down a volcano. its a form of a fast flowing mudflow

high velocity and a great momentum

1km3 to 100 km3

Mt St Helen, 1980 had a volume of 2.5 km3 and speed of 80m/s

gas emitted, sulphur, combines with atmospheric moisture

sea waves generated by violent eruption

Indonesia, 1883 tsunami killed 36,000 people

eruption can cause glacial bursts meaning serious flooding

iceland 1996

lahars, flooding, landslides, tsunamis, acid rain

fissure, shield, ash-cinder, dome, composite, caldera

basaltic, andesitic, rhylottic

low in silica so more fluid and flow further

rich in silica so more viscous, slow moving and sticky. they cause a violent eruption

destructive plate boundaries where the oceanic plate is forced beneath another plate

basalt of the oceanic slab melts into magma due to carbon content

85%

15%

rising magma plumes that provide a continue source of magma too moving plate above

hawaiian islands

repeated eruption of basaltic lava from a central vent with gentle sloping sides

steep sided convex shapes due to rhyolitic lava doesn't flow far before cooling

formed from alternating eruption of ash, tephra and lava so layer and shape is irregular

ash, cinders and tephra erupt from central vent and usually symmetrical steep side and concave shape