The weekend in Southern California was rocked by a 5.1 earthquake Friday night, with several aftershocks centered around the La Habra area.
They struck near a little-known fault, called the La Puente Hills thrust fault. Though it is less known than the larger San Andreas, scientists worry a large-scale quake along this fault could cause even more destruction in the L.A. area.
The fault runs from northern Orange County through the San Gabriel Valley and up through downtown Los Angeles into Hollywood. There are many older, more vulnerable buildings and densely populated areas along the fault than the San Andreas, which lies about 30 miles outside metropolitan L.A.
Seismologist Kate Hutton of the California Institute of Technology joins the show to talk about the risks and how to prepare for a big one on the La Puente Hills fault.