Magnitude 7.8 - SOUTHERN CALIFORNIA

SCENARIO

2008 November 13 16:00:00 UTC

Earthquake Details

Magnitude 7.8
Date-Time
Location33.350°N, -115.710°E
Depth 7.6 km (4.1 miles) set by location program
RegionSOUTHERN CALIFORNIA
Distances
  • 17 km (10 miles) WSW (245°) from Desert Shores, CA
  • 18 km (11 miles) WSW (258°) from Salton Sea Beach, CA
  • 19 km (12 miles) ENE (57°) from Borrego Springs, CA
  • 42 km (26 miles) S (176°) from Indio, CA
  • 62 km (38 miles) SSE (151°) from Palm Springs, CA
  • 108 km (67 miles) NE (54°) from San Diego, CA
Location Uncertaintyhorizontal +/- 3.8 km (2.4 miles); depth fixed by location program
ParametersNph=033, Dmin=21 km, Rmss=0.28 sec, Gp=112°,
M-type=local magnitude (ML), Version=2
Source
Event ID shakeout
  • This event has been reviewed by a seismologist.

Earthquake Summary

Small globe showing earthquakeSmall map showing earthquake

This "ShakeOut" scenario earthquake is a hypothetical, magnitude 7.8 earthquake that occurs at 10 am on November 13, 2008. Scientists at the USGS led a multidisciplinary collaboration of more than 300 experts from government, academia, emergency response, and industry to posit plausible damages and societal consequences to a major earthquake on the southern San Andreas Fault.

The earthquake occurs on a portion of the fault which poses the greatest risk of imminent rupture and is the most likely source of a large earthquake in the conterminous United States. The earthquake begins near Bombay Beach, at the southern terminus of the fault, and ruptures northwest for about 200 miles, ending near Lake Hughes. It takes about 100 seconds for this length of fault to rupture, and strong shaking lasts for as much as 3 minutes in some of the sedimentary basins of southern California, where earthquake waves get trapped and reverberate.

The ShakeOut Scenario was developed to improve earthquake readiness; it is not a prediction. However, it was assigned a date and time of occurrence because it is the basis of the largest earthquake drill in United States history, during the Great Southern California ShakeOut, with more than 5 million participants including individuals, families, schools, businesses, faith-based groups, and the 2008 statewide emergency response exercises, Golden Guardian.

Earthquake Information for California

Earthquake Summary Poster (11 Mb .pdf)

Earthquake Summary Poster