Hi All. This mornings quake in the San Ramon area occurred on the Calaveras fault. Both the "first motion mechanism" and the "moment tensor solution" indicate that it was a "pure strike slip" quake meaning that this quake was a tectonic quake. This is the most common quake to occur on the Calaveras fault in this area.

Some of the aftershocks indicate the possibility that some of the stress from this quake moved towards the southeast, or at the very least triggered other quakes on some of the parallel faults. This quake and the following aftershocks had no affect in reducing the overall stress in the Bay Area. To put it another way the probability of major quake for the Bay Area is still there. It may even be just around the corner, but there is no way at present time to know that.

It appears that there was only one foreshock to this quake. It occurred on 11/19/2002. Take Care…Don in creepy town