Scientists have warned for years that the island of Hispaniola, which Haiti shares with the Dominican Republic, was at risk for a major earthquake.
Five scientists presented a paper during the 18th Caribbean Geological Conference in March 2008 in Santo Domingo, Dominican Republic, stating that a fault zone on the south side of the island posed "a major seismic hazard."We were concerned about it," said one of the paper's authors, Paul Mann, a senior research scientist at the University of Texas' Institute for Geophysics.
"The problem with these kinds of strikes is that they can remain quiescent -- dormant -- for hundreds of years," he said Tuesday evening. "So it's hard to predict when they'll occur."
The findings by Mann and his colleagues followed a 2004 study in the Journal of Geophysical Research in which two geologists found a heightened earthquake risk along the Septentrional fault zone, which runs through the Cibao valley in the northern Dominican Republic.
"Because the earthquake was so close to the capital city, because the city is so populated and because the country is so poor -- the houses are not well-built -- it could cause significant casualties," Lin said.
But Mann believes that Port-au-Prince's modest skyline could work in its favor.
"Port-au-Prince doesn't have high-rises," said the geologist, who has visited the city. "It's mostly a low-rise kind of place. And that may be a fortunate thing for them."
The Enriquillo-Plaintain Garden fault is similar in structure and character to the San Andreas fault of California in that both are strike-slip in nature, meaning the plates move past each other in a horizontal direction, Mann said.
"The island of Hispaniola is caught between two tectonic plates," said Michael Blanpeid, associate coordinator for the USGS's Earthquake Hazards Program. "The North American and the Caribbean tectonic plates are shearing the island, crushing it, grinding it. And as that occurs, earthquakes pop off."
A dozen major earthquakes measuring 7.0 or greater on the Richter scale have occurred in the Caribbean near Puerto Rico, the U.S. Virgin Islands and the island of Hispaniola in the past 500 years, scientists said.
The last major earthquake near Hispaniola, a magnitude 8.0 in 1946, caused a tsunami and left 20,000 people homeless, according to the U.S. Geological Survey.
Source:10 March 2010,http://www.cnn.com/2010/TECH/science/01/12/caribbean.earthquakes/index.html
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Personal Response:
Through this case study of the recent Haiti earthquake, I have learned a great deal in relation to tectonic theories.
Firstly, this Haiti's earthquake of 7.0 magnitude is a result of the rupturing of the Enriquillo-Plaintain Garden fault. This occurred due to plate tectonics movement which forces the gonave microplate and the caribbean plates to slide along each other.As the edge of the two plate is not smooth, friction between the plates cause it to be locked by each other for a long time. Once the critical limit have been reached, the faults will thus rupturing which then resulted in the Haiti earthquake.
Secondly,acoording to wikipedia, this earthquake resulted in a lost of between 217,000 and 230,000 people dead, an estimated 300,000 injured, and an estimated 1,000,000 homeless. In addition, 250,000 residences and 30,000 commercial buildings had collapsed or were severely damaged. This was due to the fact that as Haiti is a LEDC, the buildings are not built to withstand earthquakes. In addition, the epicenter of the earthquake was near a heavily populated city, and thus the losses were high. From these, one can say that there are a vary of reasons which can result in the loss of life and property during an earthquake.
I hope that was a glimpse of what i had learned through this case study of the Haiti earthquake.
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