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Institute for Crisis, Disaster, and Risk Management Crisis and Emergency Management Newsletter Website |
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February
2008
Volume 14 -
Number 1 |
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Earthquakes
around the Globe in November and December 2007 and January 2008
By: Robert A. Ulizio Earthquakes pose a significant danger to over 75
million Americans in approximately 39 states. The United States Geological
Surveys (USGS) is the only Federal agency with the responsibility of recording
and reporting earthquakes nationwide. Citizens, emergency responders,
and engineers depend on the information that the USGS provides.
The USGS estimates that several million earthquakes occur in the world each year, but many go undetected. The USGS now locates about 50 earthquakes a day and about 20,000 a year. (1) There are several thousands of earthquakes that occur annually, ranging on average from 18 major quakes to more than 2 million very minor ones per year (approximately 8,000 per day). On average, we can expect one exceptionally big one (with a magnitude of 8 or higher) each year. During the months of November and December of 2007 and January 2008 there were approximately 4,600 located earthquakes that occurred around the globe. I have listed a few of the most significant earthquakes that have occurred during the aforementioned time span. The Antofagasta Earthquake was an earthquake that was registered on November 14, 2007 at 12:40 pm Chile time. The earthquake had the Ricter magnitude of 7.7 and lasted about 50 seconds. There were seventeen aftershocks of magnitudes greater than 5.0 that were registered, including one that had the magnitude of 6.8 and two others of the magnitude of 6 or higher. The epicenter was located between the localities of Quillagua and Tocopilla, affecting Tarapaca and the Antofagasta regions of Chile. The result of the earthquake left two individuals dead, forty-five injured, and buildings damaged at Tocopilla. There was also twenty people injured and buildings damaged at Marie Elena. Several thousand homes were destroyed or damaged and approximately 15,000 people were displaced in both of these areas. (2) On November 29, 2007, the strongest earthquake in the Caribbean in over 200 years struck Martinique. The earthquake registering 7.4 on the Richter scale shook several Caribbean Islands and lasted for approximately 20 seconds. Several islands felt the earthquake but a tsunami warning was not issued because the Pacific Tsunami Warning Center located in Hawaii stated that the earthquake occurred too deep to generate a destructive tsunami. The strongest quake in the Caribbean measured 7.9 in 1766. (3) The Aleutian Islands earthquake of December 19, 2007, occurred on the boundary between the North America plate and the Pacific plate. In this region, the Pacific plate moves to the northwest with respect to the North American plate with a velocity of about 72 mm/y. The Pacific plate sub ducts beneath the North American plate at the Aleutian trench. The earthquake occurred as thrust-faulting on the interface between the plates. There were no reported injuries due to this quake. (4) On December 20, 2007, an earthquake registering 6.8 on the Richter Scale which struck in the Pacific Ocean, off of the shore of New Zealand. The town of Gisborne was the town that endured the worst damage. Several buildings were destroyed, 11 people were injured and one lady suffered a heart attack and later died, following the earthquake. As of January 14, 2008, the Earthquake Commission had received over 3100 insurance claims accounting to $16 million. The early estimated costs of damage caused by the earthquake could rise to $30 million. (5) Approximately 709 deaths resulted from earthquake activity worldwide in 2007, according to the U.S. Geological Survey (USGS) and confirmed by the United Nations Office for Coordination of Humanitarian Affairs (OCHA). This is the fewest number of casualties from earthquakes in a year since 2000, when only 231 people were killed. The ground under the North Coast has been pretty active recently, with four large earthquakes registered by the Natural Resources Canada in just under a month. (6) The most recent quake took place just south of the Queen Charlotte Islands at 6:39 a.m. on January 9, 2008 and it measured 6.1 on the Richter scale. January 5, 2008 saw two magnitude 6.5 earthquakes south of the Queen Charlottes around Bella Bella at 3:01 a.m. and 3:44 a.m., while a magnitude 5.7 earthquake occurred at 3:39 p.m. on December 12 just off the west coast of Moresby Island. (6) A huge number of lives would be saved if warnings came early enough to escape an earthquake’s deadly effects. The USGS and other agencies are always working diligently in order to locate the coordinates of the earthquakes so that pertinent safety information can be passed along, in order for the public to prepare for the disaster. Although most of the U.S.’s earthquakes occur on the west coast, Robert Ketter, director of the National Center for Earthquake Engineering Research, considers it probable that a major earthquake will hit the eastern seaboard before 2010. The damage could be considerable, considering that many eastern cities are not prepared for earthquakes. (7) Sources (1) http://earthquake.usgs.gov/ (2) http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2007jsat.php (3) http://www.caribbean-on-line.com/st-barts/2007/12/major_earthquake_in_martinique.html (4) http://earthquake.usgs.gov/eqcenter/eqinthenews/2007/us2007lcaq/ (5) http://en.wikipedia.org/wiki/2007_Gisborne_earthquake (6) http://www.usgs.gov/newsroom/article.asp?ID=1846 (7) http://library.thinkquest.org/C003603/english/earthquakes/prediction.shtml |