Saturday 27 February 2010

Massive Earthquake Chile

A massive earthquake with a magnitude of 8.8 has struck central Chile, the country's largest in 25 years.
The quake struck at 0634 GMT about 91km (56 miles) north-east of the city of Concepcion and 317km south-west of the capital, Santiago.


Collapsed buildings have been reported and power loss in Santiago, early warnings of Tsunami (upto 2m recorded levels 1m) have been given, with Hawaii, Japan Alaska and West coast of America on alert.

 

NOAA Data Buoy centre
National Atmospheric and Oceanic Administration. Photograph: AFP/Getty Images

 Overall, the population in this region resides in structures that are vulnerable to earthquake shaking, though some resistant structures exist. On March 3, 1985 (UTC), a magnitude 7.9 earthquake 311 km North of this one struck Valparaiso, Chile, with estimated population exposures of 5,449,000 at intensity VII and 2,647,000 at intensity VI, resulting in a reported 177 fatalities. Recent earthquakes in this area have caused, tsunamis, landslides and liquefaction that may have contributed to losses. 

Population exposure map.

Based on Haiti Earthquake,  in which there was a 8% mortality rate, if you extrapolate this for Constitucion with a population of 38K, there is the potential for 3040 deaths and more worrying for Concepcion 215K they could be a potential loss of  17200 people? However large earthquakes have occured in this area in the past with a <% mortality rate, and early indication state that the cities buidlings seem to have resisted well so based on this the death toll could be 1-2000. ( As of March 1st 700+)

Some initial images of damage



Update 1st  March 2010
Response
Troops are being deployed to help with rescue efforts and prevent looting.

A curfew is in force in some areas. Basic supplies are to be distributed as rescuers reach worst-hit areas.
The army has been sent to support police to prevent unrest in Concepcion, south of Santiago.

The emergency measures announced by Ms Bachelet also include:
  • Air force flights to deliver supplies to affected areas
  • Free distribution of basic goods in Maule and Biobio regions - distribution points are yet to be decided
  • Efforts to guarantee electricity distribution, as many areas remain without power 
About 1.5 million homes have been damaged. Most of the collapsed buildings were of older design - including many historic structures.
About 90% of the historic centre of the town of Curico was destroyed. Many roads and bridges across the affected area were damaged or destroyed.

Why the Tsunami wasn't as big as predicted. It's also possible that the fault moved somewhat horizontally, lessening the amount of vertical displacement in the water.



But there are several other reasons why so many fewer people lost their lives this weekend. One is preparedness. Chileans knew what was coming. Reports indicate that alarms were sounded in the town of San Juan Bautista on Robinson Crusoe Islands, for example, possibly saving hundreds of lives.
That preparedness is also reflected in Chile's building codes, another lesson of the 1960 quake. Strong buildings (along with Chile's relative affluence and robust infrastructure) likely saved thousands of lives and prevented this disaster from approaching the magnitude of the continuing horrors in Haiti.



Links @
Discovery News

No comments:

Post a Comment