Please note that some of the earthquake data in this report have been reviewed by seismic analysts. Consequently, the parameters that describe the hypocenter, magnitude, origin time, and solution statistics may differ slightly from the information contained on the real-time earthquake web page. The differences reflect revised arrival times at seismic stations and the analysts' decisions to include or exclude information from seismic stations. The Bolinas earthquake was widely felt in the northern Bay Area. Shaking was strong enough that all BART trains were stopped for a short time while the tracks were inspected.
G is the acceleration of gravity.
The earthquake was near the San Andreas Fault in the section that ruptured in 1906, though the Bolinas earthquake was 60,000 times smaller than the 1906 earthquake. Unlike the typical San Andreas earthquake which shows strike-slip motion along the direction of the fault, the Bolinas earthquake showed reverse motion with compression perpendicular to the fault. This suggests that it was actually on a smaller thrust fault very close to the San Andreas. This section of the San Andreas has been quiet seismically since 1906. The largest aftershock recorded so far is M 2.6 which was 6 hours after the mainshock.