Hi Todd & Lowell,

Within a day or two after the Olympia, WA quake occurred, a local news woman was interviewing Dr. Urhammer at UCB. She asked him if it was possible that the WA quake might trigger other earthquakes around the world.

His response was yes. He said everything in the world was inter-connected and so it was possible.

From many years of watching news reports and specials regarding earthquake triggering, in time it has moved to a more accepted theory. I'm very glad to see that.

One classic case was the eruption of Vesuvius 3 days before the Great 1906 San Francisco earthquake.

As a side note, Edgar Cayce made note some years ago in saying that the next time Vesuvious has a major eruption to be cautious in San Francisco. There have been a couple of eruptions of Vesuvius since he said that, however, I don't know how large the eruption in 1906 was, thus I don't have anything to use as a comparison.

As for the historical seismicity record for the SF Bay Area, yes indeed, we did have a lot of large earthquakes in the late 1800's. Our greatest problem in making an educated guess as to if that trend might occur again is simply the lack of data. We had no seismic networks then and catalog info was on the short side. What preceeded those events today is not know with enough detail to use at this time. In 50 to 100 years, those that follow will have a much clearer view from the excellent data we have collected to date.

Petra