Alexandria, Va. — Most people are familiar with the Great 1906 San Francisco Earthquake and are aware of the earthquake risk posed to the Bay Area — and much of California — by the San Andreas Fault. Most people are not aware, however, that a cluster of large earthquakes struck the San Andreas and quite a few nearby faults in the 17th and 18th centuries. That cluster, according to new research, released about the same amount of energy throughout the Bay Area as the 1906 quake. Thus, it appears that the accumulated stress on the region's faults could be released in a series of moderate to large quakes on satellite faults, rather than a single great event on the San Andreas. But how this information might change the hazard forecast for the Bay Area is uncertain, scientists say.
Source: American Geosciences Institute