Hazards - Tectonic Hazards (Booklets 2A, 2B) Flashcards
1
Q
Earth Structure
A
- crust
- mantle
- core
2
Q
continental crust
A
- 20-200km thick
- light
- older than oceanic (3.8bn)
- rock type: granite
3
Q
oceanic crust
A
- thin: 5-10km
- dense
- younger (<200mil)
- rock: basalt
4
Q
plate motion
theory 1
A
- magma heated at the centre of earth
- rises towards the crust
- it spreads out when in contact with crust and pulls crust with it - convection currents
5
Q
plate motion
theory 2
A
- plates are v heavy so gravity acts = pulls them apart
- lithosphere cools and they become less dense, sink - slab pull
6
Q
lithosphere
A
crust + upper-most mantle
7
Q
plate tectonics evidence
jigsaw fit
A
- many continents fit together perfectly
- e.g. south america + africa
8
Q
plate tectonics evidence
fossil evidence
A
- lystrosaurus (mammal-like dinosaur) fossils found in africa, south america, india
- this dinosaur cant fly or swim
9
Q
plate tectonics evidence
paleomagnetism
A
- ships map magnetic orientation of rocks
- new rock is created in centre of ocean, old rock pushed to side
- new rock shows the current magnetic orientation imprinted on it
- patterns can be analysed to show bew rock forming
10
Q
plate tectonics evidence
climatic
A
evidence of ice sheets found in tropics - even during coldest periods impossible for ice to form in tropics
11
Q
plate tectonics evidence
geological
A
- rocks with exact same characteristics found v faraway from each other
- eg. murica east coast and wales
12
Q
earthquake + volcano location
A
- occur in linear clusters
- or plate boundaries
- clustering edge around pacific plate
13
Q
conservative plate boundary
A
- two plates slide past each other along a fault
- no volcanoes
- yes earthquakes
- as they move past each other, they stick, so pressure builds up, pressure released in sudden movement = earthquake
- eg san andreas fault in california
14
Q
destrucive plate margin: subduction
A
- continental meets oceanic = ocean trench
- convection currents + denser plate + gravity influence = oceanic plate is subducted underneath continental
- oceanic begins to melt due to friction = magma
- magma rises through lithosphere = erupts at surface = volcano chain
- pressure builds up due to plates sticking = rocks fracture = earthquake
15
Q
destructive plate margin: collision zone
A
- continental meets continental
- same density = no subduction
- sediments pushed upwards = fold mountains
- himalayas
16
Q
constructive plate margin
A
- two plates move apart bc convection currents
- magma rise up to fill gap = may less force volcano
- earthquake
17
Q
economic impact
A
effect on the wealth on an area/community
18
Q
social impact
A
effect on the lives of ppl
19
Q
environmental impact
A
effect on the ecology/landscape of surrounding area
20
Q
secondary effect
A
- results of primary effect
- eg. tsunami, wildfire, landslides
21
Q
primary effect
A
- caused by ground shaking
- includes deaths, injuries, damaga to infrastructure
22
Q
immediate response
A
- reaction of ppl as disaster happens
- immediate aftermath: food, shelter, medical care
23
Q
long term response
A
- later reactions that occur weeks/months/years
- eg. rebuilding infrastructure
24
Q
haiti
A
- 9mil pop
- 1300USD GDP per capita
- 49% adult literacy rate
- high risk from infectious diseases
25
Q
japan
A
- 126.4 mil pop
- 42700 USD GDP per capita
- 99% adult literacy
- low risk from infectious diseases
26
Q
haiti location
A
- close to boundary of caribbean and north american plates
- conservative plate boundary
27
Q
haiti
earthquake key facts
A
- 4.53pm, Jan 12, 2010
- magnitude 7
- epicenter 15km SW of Port-au-Prince
28
Q
haiti
primary effects
A
- 300,000 injured
- 222,570 deaths
- 3 hospitals collapsed
- UN headquarters collapsed
- 105,000 houses destroyed
- travel infrastructure severly damaged
- total estimated damage = 11.5bn USD
29
Q
haiti
secondary effects
A
- cholera outbreak: 5899 died, 216,000 infected
- 600,000 people left their homes
- 2mil pplliving as squatters
- 1.5mil ppl living in camps
- no communication services
- international airport damaged
- 1 in 5 jobs lost
30
Q
haiti
immediate responses
A
- rescue work done by haitians & dom rep teams
- rescue teams dug w/ bare hands for survivors
- in 24hrs Icelandic and Chinese teams arrived
- Qatar/Israel set up field hospitals
- US sent med supplies, food, water etc
- 7mil USD raised in 24hrs by US red cross
31
Q
haiti
long-term responses
A
- world bank waived haiti’s debt for 5yrs
- dom rep accepted some refugees
- 6 months after, 98% of rubble not removed - some still blocking roads
- EU gave 330mil USD
32
Q
why to
scale of disaster
A
- mag 7
- near Port-au-Prince (capital + most pop city)
- lack of preparedness
- poverty
- poor infrastructure
- logistics and coordination of relief (had to rely on international relief yet airport damaged)
33
Q
japan location
A
- boundary of pacific + eurasian plate
- subduction
- shallow focused, depth: 30km = tsunami
- plate lifted, water lifted = tsunami
34
Q
japan
primary effect
A
- earthquake shifted earths axis by 10cm
- 127,000 buildings destroyed
- coastal area of Sendai was destroyed
- oil refineries in Ichihara and Sendai caught on fire
- 4.4mil houses in NE japan lost electricity
- 1.5mil houses lost access to running water
35
Q
japan
secondary effect
A
- fujinuma dam failed
- nuclear meltdown in 3 power generators in Fukushima
- 300bil USD in damage
- tsunami caused ice slab to break off and damage property in california
36
Q
japan
immediate responses
A
- ppl went to higher ground when tsunami warning issued
- 116 countries + 28 organisations responded
- 140,000 residents were evacuted from Fukushima
- military buried dead in mass graves to prevent spread of disease
- AT&T helped ppl stay in contact free of charge
37
Q
japan
long term responses
A
- 55 nuclear reactors were taken offline = power shortages
- railway network was fully functional by september
- food exports limited due to radiation fears
- toyota and sony stopped production + other companies relocated
- 330,000 victims were still homeless
