Earthquakes in Guatemala

Earthquakes and tremors are relatively frequent occurrences in Guatemala. The country lies in a major fault zone, known as the Motagua and Chixoy-Polochic fault complex, which cuts across Guatemala and forms the tectonic boundary between the Caribbean plate and the North American plate. In addition, along Guatemala's western coast line, the Cocos plate pushes against the Caribbean plate forming a subduction zone known as the Middle America Trench, located approximately 50 km off Guatemala's Pacific coast. This subduction zone led to formation of the Central America Volcanic Arc, and is an important source of offshore earthquakes. [cite web |url=http://www.diva-portal.org/diva/getDocument?urn_nbn_se_uu_diva-3389-1__fulltext.pdf | publisher= |title=Earthquake Sources and Hazard in Northern Central America |year=2003 |location=Upsala |author=Cáceres Calix, José Diego | access_year=2008 | format=pdf] Both these major tectonic processes have generated deformations within the Caribbean plate and produced secondary fault zones, like the Mixco, Jalpatagua, and Santa Catarina Pinula faults. [cite web | url=http://www.insivumeh.gob.gt/geofisica/indice%20sismo.htm | publisher= | title=Marco tectónico para Guatemala | author=INSIVUMEH | access | format=]

The most destructive earthquake in recent Guatemalan history was the 1976 quake with a magnitude of 7.5 M_w and an epicenter depth of just 5 km. This shallow-focus earthquake, originating from the Motagua Fault, caused 23,000 fatalities, leaving 76,000 injured and causing widespread material damage. Surprisingly, the 7.9 M_w earthquake of 1942 -though higher in magnitude- was much less destructive, in part because of its substantially larger epicenter depth of 60 km.cite web | url=http://www.insivumeh.gob.gt/geofisica/indice%20sismo.htm#PRINCIPALES%20EVENTOS%20S%CDSMICOS%20DEL%20SIGLO%20XX%20EN%20GUATEMALA | publisher= | title=Principales eventos sísmicos del siglo XX en Guatemala | author=INSIVUMEH | access | format=]

A number of earthquakes with low magnitudes caused major damage in very localized areas, which may in part be explained by their relatively small epicenter depth. This was the case with the 1985 Uspantán earthquake of 5.0 M_w with an epicenter depth of 5 km, which destroyed most buildings in the town of Uspantán, but caused little or no damage in the rest of the country. [cite web | url=http://www.insivumeh.gob.gt/geofisica/indice%20sismo.htm | publisher= | title=Marco tectónico para Guatemala | author=INSIVUMEH | access | format=]

Recent earthquakes

Notable earthquakes in recent Guatemalan history include the following:

See also

* Geography of Guatemala
* Motagua Fault

Notes

References

:cite book
last=Marshall
first=Jeffrey S.
authorlink=
coauthors=
editor=Bundschuh, Jochen & Guillermo E. Alvarado (Eds)
others=
title=Central America: Geology, Resources and Hazards
origdate=
origyear=
origmonth=
url=
format=pdf
accessdate=
accessyear=
accessmonth=
edition=
series=
volume=
date=
year=2007
month=
publisher=Taylor & Francis
location=
language=
isbn=978-0415416474
oclc=
doi=
id=
pages=1-30
chapter=The Geomorphology and Physiographic Provinces of Central America
chapterurl=http://www.csupomona.edu/~marshall/jsm.pubs/Marshall.06.pdf
quote=
ref=: cite book |author=aut|Tucker, Brian E., Mustafa Erdik, Christina N. Hwang (Eds.) |year=1994 |title=Issues in Urban Earthquake Risk |location=Dordrecht |publisher=Kluwer Academic Publishers |isbn=0-7923-2914-7 |oclc=

Sources

* [http://www.insivumeh.gob.gt/geofisica/indice%20sismo.htm Seismic data of Guatemala] , Retrieved on July 28, 2008
* [http://earthquake.usgs.gov/regional/world/historical_country.php#guatemala details on Historic Earthquakes in Guatemala] . Retrieved on July 28, 2008.

External links

* [http://www.insivumeh.gob.gt/ Instituto Nacional de Sismología, Vulcanología, Meterología e Hidrolagía (INSIVUMEH)]