Indonesian earthquake 2004
31 December 2004
by Richard
Conan-Davies
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So what was happening to cause that massive tsunami that has caused so much damage and loss of life? It was an undersea earthquake that measured 9.0 on the richter scale which makes it the 4th largest earthquake to be recorded. The size of the area that actually shook had maximum length of 1200 -- 1300 km parallel to the Sunda trench and a width of over 100 km . The fault line was estimated to have move some. Dr Cvetan Sinadinovski, Duty Seismologist with Geoscience Australia explained that "This is the largest earthquake in the world for forty years, and the fifth largest in the world since 1900," Earthquakes this large tend to cause tiny changes in the Earth's rotation by change in length of day: -2.676 microseconds which is not really measurable. This earthquake is also described as a megathrust earthquake because it is the result of one of earth's tectonic plates sliding under another. This builds up pressure over along time but eventually the pressure is too great for the rock and the whole fault line shifts. |
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Related Links
Geoscience Australia news release
Wikipedia Article on 2004 Tsunami
Tsunamis
ClearlyExplained.Com
Nature &
Science News
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