Pisco earthquake
August 15th 2007
The Pisco earthquake is the strongest ocurred in the central region of Perú in the last 100 years, 7.9 Richter, and featured presenting a very complex breaking process with an evident unilateral propagation pattern toward southeast...
According with the location of the hipocenter (the point down deep in earth’s crust where the failure happened) the earthquake was originated by the plates friction mechanism within the continuous converging process that is happening along the western side of Perú, in other words the Nazca plate subduction underneath the continent generating earthquakes of different magnitudes at different depths above 60 km. The speed of this process is 7 – 8 cm per year
The earthquakes generated are frequent in terms of time in a year up to 60 earthquakes happen with magnitudes equal or higher than 4.5 Richter and in general most of them are felt in locations near the epicenter.
Earthquakes stronger than 7.0 have caused severe damages in extense areas like the one occured on June 21st 2001, 8.2 Richter, affecting an area of 370 x 70 km between Atico (Arequipa) and Ilo (Moquegua) .
Inland earthquakes also happen but magnitudes are 6.5 or less and are less frequent and caused by the deformation of the earth crust due to the converging plates.
Earthquakes deeper than 60 km also happen caused by the intern deformation of the Nazca plate under the continent but are rarely felt in the surface like the one that happened on September 25th 2005, 7.2 Richter. Did any of you felt it?
The Pisco earthquake showed two important characteristics, first its high magnitude 7.9 and the long duration observed for its breaking process with evident unilateral southeastward propagation pattern... |
