Poster of the Puerto El Triunfo, El Salvador Earthquake of 8 August 2012 - Magnitude 7.3

Tectonic Summary

The August 27, 2012 M 7.3 interface between the Cocos and Caribbean plates. At the epicenter of this earthquake, the Cocos plate moves north-northeast with respect to the Caribbean plate at a velocity of approximately 73 mm/yr, and subducts beneath Central America at the Middle America Trench.

This plate boundary region has experienced over 20 earthquakes of magnitude 6 or greater over the past 40 years; three of these had magnitudes greater than 7. The largest of these were M 7.7 earthquakes in September 1992, approximately 140 km to the southeast of the August 26 earthquake, and another M7.7 earthquake in January 2001, 85 km to the north of this event. The 1992 earthquake spawned a large and damaging tsunami along the coastline of Central America, particularly in Nicaragua and Costa Rica, and resulted in over 100 fatalities. That earthquake has been labeled a tsunami earthquake, characterized by the unusually large tsunami it caused in relation to the size of the earthquake. The 2001 earthquake offshore of El Salvador resulted in over 850 fatalities, many of which were caused by large landslides in multiple El Salvador cities.


Thumbnail image of poster.


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