M 8.0 - 41 km SW of San Vicente de Cañete, Peru

Tectonic Summary

The August 15, 2007, M 8.0 earthquake near the coast of central Peru occurred as the result of shallow thrust faulting about 100 km east of the Peru-Chile Trench and on the subduction zone interface between the Nazca and South America plates. At the location of the earthquake, the two plates converge at a velocity of about 77 mm/yr, with the South American plate moving up and seaward over the Nazca plate. The earthquake location, depth, and focal mechanism solutions indicate that the source of the earthquake was likely along the interface between the two plates.

While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Thrust-faulting events of the size of the August 15, 2007, earthquake are typically about 150x65 km (length x width); modeling of this earthquake implies dimensions of about 120x140 km, predominantly up-dip of the hypocenter.

Coastal Peru has a history of very large earthquakes. The August 15th event originated just south of the source region of the M 8.1 earthquake of October 1974 and just north of the source regions of major earthquakes that occurred in August 1942 (M 7.7) and November 1996 (M 7.7). The largest coastal Peru earthquake of the last two centuries was the M 9 earthquake of 1868, which was centered about 700 km southeast of the August 15th earthquake. The 1868 event produced a tsunami that resulted in several thousand fatalities along the South America coast and also caused damage in Hawaii.

Hayes et al. (2016) Tectonic summaries of magnitude 7 and greater earthquakes from 2000 to 2015, USGS Open-File Report 2016-1192. (5.2 MB PDF)