Preliminary Report on the 29 July 2008 Mw 5.4 Chino Hills, Eastern Los Angeles Basin, California, Earthquake Sequence

The 29 July 2008 Mw 5.4 Chino Hills earthquake was the largest event to occur within the greater Los Angeles metropolitan region since the Mw 6.7 1994 Northridge earthquake. The earthquake was widely felt in a metropolitan region with a population of more than 10 million people and was recorded by hundreds of broadband and strong-motion instruments. In this report we present preliminary analysis of the event and discuss its significance within the seismotectonic framework of the northern Los Angeles basin as revealed by previous moderate earthquakes.

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