Geography - tectonic hazards

Tectonic Hazards

What were the impacts of the boxing day tsunami.

230,000 dead

millions displaced

widespread destruction over 14 countries

What were the impacts of the japanese tsunami?

120,000 buildings collapsed

18000 dead

level 7 nuclear reactor meltdown

Who are some of the key players in both tsunamis?

British red cross

TNCs

National government

USCGs

What are some comparisions between both tsunamis?

early warning systems vs no warnings

HICs vs LICs

1 country effected vs 14 countries

When did the indian ocean tsunami take place?

Boxing day 2004

When did the japanese tsunami happen?

11th march 2011

What are the 5 terms in the hazard profile?

frequency

areal extent

duration

spatial predictability

speed of onset

magnitude

What are the 4 stages in the park model.

mitigation

preperation

response

recovery

What were the impacts of the Boxing Day tsunami?

230,000 dead

Millions displaced

Widespread destruction over 14 countries

Accretion wedge

A mass of sediment built up on the edge of an overriding plate at a plate boundary

Asthenosphere

The mechanically weak, ductile upper layer of the Earth's mantle lying directly below the lithosphere, where convection currents occur.

Continental drift

The gradual movement of the Earth's continents across the ocean bed over geological time.

Convection currents

The circular movements of molten rock in the Earth's mantle caused by heat differences, which drive tectonic plate movement.

Hot spot

Volcanoes found away from the plate boundary, due to a magma plume closer to the surface

Lithosphere

The upper crust of the earth (100km thick)

Paleomagnetism

1. the branch of geophysics concerned with the magnetism in rocks that was induced by the earth's magnetic field at the time of their formation.

seismic waves

A wave of energy produced by an earthquake that travels within the earth or along its surface

Slab pull

The tectonic plate being pulled into the mantle via convection currents in the mantle

Archipeligo

A collection of islands scattered in a body of water

Benioff zone

The zone where subduction causes crustal rocks to melt

Define Hazard

A perceived natural event that has the potential to threaten life or property

Define disaster

The realisation of a hazard, when it causes significant impact on a vulnerable population.

What is the criteria for a mega disaster?

2000 deaths

200000 homeless

GDP reduced by 5 percent

Dependence on aid for a year after

Definition and examples of geophysical hazards

Triggered by processes of the earth

volcanoes

earthquakes

avalanches

tsunamis

Definition and examples of hydrometeorogical hazards

Triggered by the weather or climate processes

floods

typhoons

hurricanes

What are the 5 theories of Alfred Wegner?

Jigsaw fit

Rock type/ age/ formation

Coal in Antarctica and India

Fossil evidence

Tectonic Fit

What is paleomagnetism?

Magnetic reversals: Earth's magnetic poles completely flip every few hundred thousand years (North becomes South, and vice versa), and rocks preserve a timeline of these flips like a barcode.

What is sea floor spreading

Seafloor spreading creates symmetrical magnetic "stripes" on the ocean floor, acting as a historical tape recorder of Earth's magnetic field reversals.

What is the Risk equation?

Risk = Hazard * Vulnerability/ Capacity to cope

The 6 Hazard profile definitions

Magnitude

Duration

SON

Spatial predictability

Frequency

Spatial area

The number of total disasters recorded has…

increased

Number of fatalities has…

decreased

total number of people affected has..

increased due to population increase

The economic effects have…

increased

What is a lahar

- A flow of mud and debris

pyroclastic flow

A mixture of gases and rock fragments, at high temperatures travelling at rapid pace