http://www.oes.ca.gov:8001/html/usgs_maps.html
The U.S. Geological Survey in Menlo Park Earthquake Maps page provides information on California earthquakes for the last 72 hours. The page has connections to maps for Cape Mendocino, San Francisco, Monterey, Parkfield, and Los Angeles, providing their current seismic activity. There are links to weekly summaries and recent plotted quakes.