EARTHQUAKES

What are earthquakes?

• It is the release of energy waves called seismic waves in the crust of earth, leads to the creation of a natural disaster

called earthquake.• The shaking could last seconds

or minutes, and there may be several earthquakes over a

period ranging from hours to weeks called foreshocks and

after shocks, the later decreasing in magnitude with

time.

What caused earthquakes?

It is caused by the breaking and shifting of rocks beneath the earth surface.

Or called a sudden slip on a fault.

Faults are the surface where when two blocks of the earth suddenly slip past one another.

The Greatest Earthquakes

• Seismograph; the measurement of earthquakes

The Sumatera Earthquake

WHEN? December 26th 2004WHERE? The west coast of Sumatra, Indonesia. (Sumatra–

Andaman earthquake) Indonesia (mainly in Aceh) Sri Lanka India (mostly in Tamil Nadu) Thailand Maldives Eastern coast of Africa (mostly by tsunami,

especially Somalia)

Signs & Warnings

Earthquakes cannot be predicted by any kinds of tool or humans.

By the time the earthquakes came, the animals behaved unusually which made the minority of the people in Banda Aceh and other regions panicked.

Earthquakes with 8 magnitudes or higher are highly possible to have Tsunami.

The victims

According to geological survey, 227,898 people died across the countries that suffered from the Earthquakes and Tsunami.

This earthquake was the biggest in the Indian Ocean in some 700 years, or since around A.D. 1400 and also the third most powerful earthquake recorded since 1900, and the confirmed death toll is just under 200,000 due to the ensuing tsunami.

The damaged Humanitarian: widespread

damage of the infrastructure, shortages of food and water, and economic damage.

Economic: damage of industries, fishery, and tourism

Environmental: enormous environmental impact that will affect the region for many years to come. It has been reported that the damage has been inflicted on ecosystems such as mangroves, coral reefs, forests, coastal wetlands, vegetation, sand dunes and rock formations, animal and plant biodiversity and groundwater.

Aftermath Across Aceh, thousands of houses were

built with foreign aid in what were once wastelands. In Banda Aceh, the provincial capital, new homes surround a 2,600-ton ship pushed a mile inland by the Tsunami. It is now a tourist attraction.

There is a new hospital and airport, and tourist shops selling I-love-Aceh T-shirts.

References

What is earthquake, vtaide, [online] http://www.vtaide.com/png/George/earthquake.htm [accessed on 17th April 2012]

Earthquakes, Faults, Plate Tectonics, Earth Structure, USGS, (2009) [online] http://earthquake.usgs.gov/learn/faq/?categoryID=1&faqID=96 [accessed on 17th April 2012]

What is an earthquake, windows to the universe (2010) [online] http://www.windows2universe.org/earth/geology/quake_1.html [accessed on 17th April 2012]

Hazards, Geoscience Australia (2011) [online] http://www.ga.gov.au/hazards/earthquakes/earthquake-basics/what.html [accessed on 17th April 2012]

What are earthquakes (1998) [online] http://scign.jpl.nasa.gov/learn/eq1.htm [accessed on 17th April 2012]

Largest Earthquakes in the World Since 1900, Earthquake Hazards Program (2012) [online] http://earthquake.usgs.gov/earthquakes/world/10_largest_world.php [accessed on 16th April 2012]