GCSE Hazards Revision

Haiti Earthquake and Montserrat Volcano

Types of Plate Boundary

Earthquakes

• Occur along FAULT LINES.• Movements in the ground due to sudden release

of friction in the form of SEISMIC WAVES.• The FOCUS is inside the earth’s crust where the

earthquake happened.• The EPICENTRE is the point on the Earth’s surface

above the focus, where the shakes are strongest.• Measured using the RICHTER SCALE where each

number is 10 times greater than the last

Earthquakes

Earthquakes - Haiti

• 12th January 2010• Haiti is an island in the Caribbean Sea• Magnitude measured 8.0 on the Richter Scale

• Conservative plate boundary – N. American plate moving past the Caribbean plate

Earthquakes - Haiti

Primary Effects– 200 000 deaths– 3 million people left homeless, moved into tents– 8 hospitals damaged in Port-au-Prince (capital)

Secondary Effects– The Haitian tourist industry declined– Outbreaks of disease eg. Cholera– Destruction of government buildings made the

island difficult to control, the police force collapsed

Links?

Earthquakes - Haiti

Responses

Aid struggled to get to those who needed it most because of the damaged

infrastructureOverseas aid agencies eg. Oxfam, Red Cross

Social media such as Facebook and twitter used to spread messages

Trying to rebuild healthcare and agriculture but not enough money

Earthquakes - Haiti

Reducing the Effects of Earthquakes• Earthquake proof buildings (MEDC and LEDC)

• Earthquake drills (regular practices)

• Preparing and planning in the home (earthquake kits)

• Earthquake prediction amps and shaking maps

• Overseas aid and rebuilding

WHICH OF THESE ARE SHORT TERM?

WHICH ARE LONG TERM?

Why do people live near earthquakes?

Family and friends live

there

Many plate boundaries are near the coast (best land for farming/trade)

They cannot afford to live

anywhere else

Worth the risk – unlikely that an earthquake will happen in their

lifetime

Volcanoes

Volcanic bombs, ash, lava, gases

Magma chamber

Parasitic cone

Crater

Main vent

Volcanoes

ActiveVolcano has

erupted recently

DormantVolcano has

erupted in the last 2000 years, but

not recently

ExtinctVolcano unlikely

to ever erupt again

Volcanoes – Soufriere Hills

• Destructive plate boundary• In the south of the Caribbean island of

Montserrat• Much of the population are poor and rely on

subsistence farming• Having been dormant for 500 years the

volcano erupts in August 1995 and again in 1997

Volcanoes – Soufriere Hills

Primary Effects– 50% of people evacuated to the North to live in shelters– 19 people dies– Pyroclastic flows destroyed farms and started fires– 2/3 of island covered in ash– Plymouth (capital) turned into a ghost town

Secondary Effects– Poor sanitation and crowding in the North– Tourist industry still suffering– Over half the population have not returned after they

were evacuated

Links?

Volcanoes – Soufriere Hills

Responses

Helicopters from France help to find

missing people

Medical assistance from

neighbouring Caribbean islands

Many people still relying on

aid 15 years later

How could Montserrat reduce their

dependence on aid?

Volcanoes

Reducing the Effects of Volcanoes• Improved warning

• Better buildings – smooth, sloped roofs to prevent ash build up

• Education – what to do if the volcano erupts

• Prevent/restrict building on land vulnerable to effects

• Emergency kit for households…

Volcanoes

Emergency Kit• Non-perishable food• Torch• First aid kit• Water• Radio• Whistle• Blankets• Face masks and goggles

Why do people live near volcanoes?

People feel an eruption will not

occur in their lifetime

Those in LEDCs often cannot

afford to move away

Geothermal energy for example in

Iceland

Tourism from those wanting to see the dramatic

landscape

Fertile soils producing

better crops