Tuesday, March 30, 2010

Chile's earthquake


A massive earthquake has hit the coast of Chile, killing more than 100 people, flattening buildings and triggering a tsunami.

The 8.8-magnitude quake shook the country for a minute and half at 3:34am (6:34am GMT) today.

A tsunami warning has been extended across 53 countries, including most of Central and South America and as far as Australia and Antarctica.

The wave has already caused serious damage to the sparsely populated Juan Fernandez islands, off the Santiago coast, and is now travelling across the ocean at several hundred km per hour.

People in the Galapagos and on Easter Island have already taken refuge, while the US has started evacuating the shoreline communities of Hawaii.

At least 122 have been killed in the quake, according to Chile’s national emergency office.

President Michelle Bachelet has declared a “state of catastrophe” in the country. Calling for calm from an emergency response centre, the outgoing president said: “We have had a huge earthquake, with some aftershocks.

“Despite this, the system is functioning. People should remain calm. We’re doing everything we can with all the forces we have. Any information we will share immediately.”

The quake hit near the town of Maule, 200 miles southwest of Santiago, at a depth of 22 miles underground.

The epicentre was just 70 miles from Concepcion, Chile’s second-largest city, where more than 200,000 people live along the Bio Bio river.

TV Chile reported that a 15-storey building collapsed in the city, while other buildings caught fire and massive cracks opened up in the streets and bridges.

Cars turned upside down lay scattered across one damaged bridge.

Dozens of people were seen roaming through the streets, some wheeling suitcases behind them and others gathering around open fires to keep warm.

Many are terrified by the powerful aftershocks and are desperately trying to call friends and family.

The telephone and power lines are down in much of central Chile, making it difficult to assess the full extent of the damage close to the epicentre.

Chile is the world’s top copper producing country and the quake halted operations at two major mines.

“Never in my life have I experienced a quake like this, it’s like the end of the world,” one man told local television from the city of Temuco, where the quake

forced staff to evacuate the regional hospital.

Santiago airport has been shut down and will remain closed for at least the next 24 hours after the passenger terminal suffered major damage.

In Talca, just 65 miles, from the epicentre, neighbours pulled at least five people from the rubble while emergency workers, themselves disoriented, asked for information from reporters.

The Foreign Office has updated its travel information for people planning to go to Chile, saying: “The Foreign and Commonwealth Office is in contact with our embassy in Santiago in order to establish the facts on the ground.

“Communications are sporadic. We will update this advice over the next few hours.”

The Chilean ambassador, Rafael Moreno, said he was trying to help worried British-based relatives make contact with their families in the country.

In the coastal city of Vina del Mar, the earthquake struck just as people were leaving a disco, Julio Alvarez told a local radio station. “It was very bad, people were screaming, some people were running, others appeared paralyzed. I was one of them.”

Several big aftershocks later hit the south-central region, including ones measuring 6.9, 6.2 and 5.6.

The earthquake was caused by the floor of the Pacific being pushed below South American land mass.

This sudden jerking of the sea-floor displaced water and triggered a tsunami, which is now crossing the ocean at a speed of a jet plane.

The Pacific Tsunami Warning Center issued a warning for Chile and Peru, and a less-urgent tsunami watch for Ecuador, Colombia, Panama, Costa Rica and Antarctica.

A spokesman said: "Sea level readings indicate a tsunami was generated.

"It may have been destructive along coasts near the earthquake epicentre and could also be a threat to more distant coasts."

All Pacific islands including the Hawaii and the Easter Islands have also received warnings.

US Civil Defense officials in Hawaii said they were preparing to start evacuations from shoreline communities.

The Joint Australian Tsunami Warning Center also warned of a “potential tsunami threat to New South Wales state, Queensland state, Lord Howe Island and Norfolk Island".

Any potential wave would not hit Australia until Sunday morning local time, it added.

On the Easter Islands people are now seeking higher ground before the wave strikes.

Earthquakes are relatively common in Chile, which is part of the pacific “ring-of-fire” tectonic-plate boundary, and many buildings are built to withstand tremors.

The largest earthquake ever recorded struck the same region on May 22, 1960. The magnitude-9.5 quake killed 1,655 people and left two million homeless.

The tsunami that it caused killed people in Hawaii, Japan and the Philippines and caused damage to the US West Coast

source: 30 March 2010 http://www.timesonline.co.uk/tol/news/world/us_and_americas/article7043637.ece

Personal Responses:

The earthquake of magnitude 8.8 devastated Chile at 3.34 in the morning. This is the time where most people are in bed and resting at home. However, during the earthquake that lasted for one and a half minutes,only around 122 people were killed. For a disaster of such magnitude, i feel that 122 death is considered a really small amount. This relatively low death rate is due to the fact that the buildings were build to withstand earthquakes. This directly brought down the death rate significantly.

Personally, i felt that these earthquake proof designs were only possible because of Chile's economic wealth(Chile is the world top copper producer). In addition, Chile is also efficient in the sense that they also have protocols in place in the event of any such major disaster, which took effect after the earthquake happened.This in turn help reduce panic and chaos, and quickly put the situation under control. To top it off, due to the technological advancements of the nation, they predicted that a tsunami was generated and issued a tsunami warning to those possible affected areas which could also directly reduce lost of lives.

Ultimately, the ability to predict these natural disaster or to mitigate it, lies in the hand of those that can afford it.






Friday, March 12, 2010

Haiti's earthquake




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.



Thursday, March 4, 2010

First entry

HI ALL! This is my first post on this blog. This blog is part of my assessment for my geography subject in my foundation program. Sadly, i dont blog, so i cannot make fancy skins and all.
Geography to me had always been only just an academic subject and thats about it. However, with the recent string of natural disasters, I realise Geography have a more intimate relation with humans than I had felt in the past. This have spiked my interest in the subject. So, here is my geog blog. :)