Hi All,

I had a really usual morning, but one that proved to be rather special. As I was making my way to Sonoma to work this morning, I found getting there by my usual route was impossible. There was a fatal accident along a narrow two lane stretch, so I had to go around the long way.

But I had an amazing surprise by going the long way round. For the first time I drove around the base of the Rodgers Creek Fault along the eastern side, and what lies over there is nothing like the west side.

Just passing what used to be called Sears Point Raceway, near Blackpoint, I saw two tall peaks. While they were rounded at the top, they are totally different from the topography of the west side where everything is a series of rolling hills. I also noticed at the base of these peaks on both sides of the road there were huge pumice rocks. This is the location where I believe the USGS wanted to install monitoring equipment some time ago, but ran out of funding for the project. It reminded me so much of the road that leads from Red Bluff to Lassen Volcano which is strewn for miles with volcanic debris.

What is interesting about the Sonoma Volcanic's is that there are places where there is much volcanic debris of one sort or another, but no one has to yet to identify where this volcanic matter originated. Near Calistoga, for instance is the Petrified Forest. A series of trees became petrified in volcanic ash and yet there is no answer as to where this ash came from. The entire area around the Rodgers Creek Fault is volcanic in origin and yet, no known volcano's have erupted to such a degree that they can figure this out. Now isn't that strange?

The location in Bennett Valley where the epicenter of the 4.5 quake occurred in 1999 has volcanic bombs all over the place and the closest volcanic peak, Mt. Taylor is said to have only been an oozing volcano and never erupted.

Seems there is much to study yet in this area and perhaps in the future more scientists will take an avid interest in my backyard buddy and eventually locate where this volcanic matter originated.

So a little deviation from the normal, once in a while, can prove to be just what an earthquake chaser needs.

Petra

• The Seismic Safety Zone