The earthquake that shook Haiti last week described by the United Nations (UN) as the worst humanitarian crisis in decades, with an estimated death toll between 50,000 to 200,000 people.
UN menengarai number of casualties in Haiti since the earthquake struck a densely populated capital, which has hindered the movement of many institutions working for disaster relief.
Meanwhile, geologists who spoke to New Scientist revealed other reasons why Haiti is so great earthquake and warned that more powerful shocks will soon follow, because not all latent energy released in an earthquake tragedy.
First, the epicenter of the earthquake occurred at shallow so do not give enough time to warn residents to get out of the building. This is different from the earthquake in episentrumnya.
Second, Port au Prince is built not on rock but on the clay that vanish as soon as a shock.
Finally, the standard building could not resist a great earthquake.
If the same earthquake hit California, the number of casualties almost certainly be lower. "Construction of a better building will save many human lives," said Chuck DeMets, tectonic geologists from the University of Wisconsin-Madison.
The story of two earthquakes
Comparison between the following two earthquakes are very similar to each other can strengthen the claim that Chuck DeMets.
The second earthquake was very similar to the same place in densely populated areas, but the victims of the earthquake caused much different from each other.
In 1988, an earthquake of 6.9 on the Richter scale shook the Spitak in Armenia claimed 25,000 lives. In contrast, an earthquake measuring 7.1 on the Richter scale that shook the Loma Prieta in California in 1989 "only" 63 people took casualties.
"The difference in the number of victims of the disaster showed the buildings berstandard (anti-earthquake) high can save lives of people," said DeMets.
Storey buildings surrounding almost the entire Port-au-Prince proved a death trap when the earthquake hit.
"Storey buildings were fragile and did not have the flexibility, causing havoc when hit by an earthquake," said Ian Mai, seismolog from the University of Edinburgh, UK.
And the disaster was made worse by a shallow earthquake epicenter.
"In an earthquake with epicenter in, which first appeared is the main wave, and give you a little warning before the wave fault (that shook the earth from side to side) up," said Uri ten Brink, Caribbean earthquake experts from the U.S. Geological Survey (BMG his U.S.) in Woods Hole, Massachusetts.
In Haiti earthquake, epicenter of the quake was so close to the earth's surface so that the main wave and the wave fault occurred almost simultaneously.
Designed to survive
So, building a model of how that could hold such shocks?
"The engineers use the more flexible material with an installed capacity that can absorb damage, such as the hood of a car today that is designed to be folded so that the interior remains intact," said Main.
"This may include primary isolation shock absorbers on the first floor, to help stop or minimize the waves and dynamic fault movement rolling."
Adjustment of ordinary buildings to withstand earthquakes is expensive, but the new building earthquake-resistant is not expensive.
"Building gampa resistant building material which requires little more design time and require a little longer, but the buildings were no more expensive than regular buildings," said Main.
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