spring-2017

Recent innovations in the use of ambient noise and dense seismic arrays have allowed a new look at earthquakes, seismic hazard, and tectonics of the Los Angeles region. Some of the interesting observations that are revealed are: 1) Site amplification due to near surface effects can vary by a factor of five over a horizontal scale of 1 km, which means it is aliased by the existing seismic network. 2) There is a 5-8 km step in the Moho near the coast. 3) Seismicity under the Newport-Inglewood fault is vertical and penetrates at least 5 km into the mantle, and 4) the Los Angeles Basin actually has a hard bottom