GCSE Geography

• primary effects 
• secondary effects

shaking (the severity of which is dependant upon the magnitude of the quake , the distance from the epicentre , the depth of the focus etc)

• liquefaction 
• landslides/avalanches 
• tsunamis 
• aftershocks
• destruction of the built environment
• fires and explosions

the top layers of the ground turn into a liquid type substance as the shaking filters solid particles of soil further down into the earth

solid/rock etc slip down slopes

huge sea waves that flood inland

smaller , but still dangerous periods of shaking of the ground as the tectonic plates chill out and settle back down

buildings , bridges , tunnels , roads etc that have been weakened by the quake often collapses (especially if there are aftershocks)

gas pipes burst and electricity power lines may snap

giant sea wave generated as a result of a shallow focus underwater earthquake

2004

• there's a destructive plate margin along the west coast of Indonesia in the Indian ocean 
• on the 26th of December 2004 there was an earthquake off the west coast of the island Sumatra measuring around 9.3 on the Richter scale 
• the plate that's moving into the mantle cracked and moved very quickly , which caused a lot of water to be displaced , this triggered a tsunami which waves up to 30m high

Tsunamis are most often caused when an earthquake causes the seafloor to rise or fall. Earthquakes happen when two tectonics plates collide into each other at a plate boundary. The denser plate is subducted under the other plate, which leads to a rise or fall of the seafloor. This movement of the seafloor will cause a rapid vertical displacement of water, and waves of a tsunami would form. As the wave approaches the coastline, it would get higher as the seafloor gets shallower, causing a tsunami to become visible and then grow even higher as the water gets more shallow. The shock waves produced by the earthquake would radiate out and cause other waves to form too.

it affected most countries bordering the Indian Ocean e.g. : Thailand , India , Sri Lanka

there was no early warning system

• around 230 000 people were killed or still missing 
• whole towns and villages were destroyed - over 1.7 million people lost their homes
• the infrastructure of many countries was severely damaged 
• 5-6 million people needed emergency food , water and medical supplies 
• there was massive industrial damage . Millions of fishermen lost their livelihoods , and the tourism industry suffered because of the destruction and people were afraid to go on holiday there 
• there was massive environmental damage . Salt from the seawater has meant that plants can't grow in many areas . mangroves , coral reefs , forests and sand dunes were also destroyed by the waves

• within days hundreds of millions of pounds had been pledged by foreign governments , charities , individuals and businesses to give survivors access to food , water , shelter and medical attention
• foreign countries sent ships , planes , soldiers and teams of specialists to rescue people , distribute food and water and begin clearing up

• billions of pounds have been pledged to help re-build the infrastructure of the countries affected 
• as well as money , programmes have been set up to re-build houses and help people get back to work 
• a tsunami warning system has been put in place in the Indian Ocean 
• disaster management plans have been put in place in some countries . volunteers have been trained so that local people know what to do if a tsunami happens again

how differing levels of economic development (LEDC vs MEDC) have a massive effect on the impact an earthquake will have

Kobe Japan

Maharastra state , India

1995

7.2

5400

1993

6.4

22000

• unlike India Japan could afford to have : early warning systems for tsunamis ;
• quake proofing techniques for buildings , bridges and tunnels ;
• well prepared and developed emergency drills , routines and emergency services ;
• lots of emergency equipment , facilities , doctors and nurses ;
• emergency management organizations and monitoring agencies specifically set up to prepare for the earthquakes and try to predict them

3000

• shallow 
• 19

• sea 
• offshore

15000

• shallow 
• 17

Killari village in the Latur village a densley populated area . The population of this area is 2 million

• the poor quality of the buildings
• the poor quality/lack of emergency services 
• the shallow depth of the focus
• the location of the epicentre
• in most LEDC's the authorities simply don't have the resources to deal with 1000's of injuries and people made homeless
• they also cannot afford to quake proof buildings also they don't have organizations to make building quality control laws and ensure they are enforced