Hi Don,

Shoulder to the wheel! Actually both Don and I feel taking a closer look at the North Bay area is needed at this time. I'm attaching a link that describes the recent Yountville quake and makes note of the Bolinas and Rohnert Park quakes.

There is a very good map with this link and I'd like to ask you to take a look at something interesting. Notice Yountville is due east of where the 4.3 Rohnert Park quake occured. Then we have Bolinas down to the southwest and Vallejo to the southeast. Now triagulate them and its hard not to miss the correlations, at least in my estimation.

Don is right about the quake in September not being on the RCF directly. It was in an area known as Bennett Valley, one that had a volcanic past. Mt. Taylor at one time was an oozing volcano and in one of our recent field adventures we collected volcanic bombs from that locale.

So what's so fascinating about the Northbay? Since Bolinas last year, we've had an obvious increase of noteable seismicity. Is it leading to something larger? Well, this requires further investigation. Thus b value is one method of understanding whether each area has a value different than the others, or are they similar? Yountville seems to be much quieter in the past than the other area's, so will these recent events be a flash in the pan, or the beginning of something new? Worthy of watching for sure.

So have a look at the link if you like.

Petra

• Yountville Quake & Other Associated Area's