John,

Perhaps we should throw in a +/- 5% accuracy depending on those who created the catalog huh? There may be two quarries in the SF Bay Area, but I don't know about a 40 mile radius around the center of LA. Do you? Also, you didn't say when the last person did a study. Was it recently? Did it cover any of the same time period or locations as we are attempting to cover? I'd hate to be redundant. LOL

As I understand it, people who are using B Value studies, use catalogs as well to make their assumptions about fault behavior and sometimes its over a long period of time. Do they take the time to make catalog corrections as well? If not, does that mean these studies are not correct? As a somewhat casual observer of B value, I really don't think it is all that useful in predicting earthquakes. Do you have a learned opinion about it?

It's a good thing I don't often buy into others lack of optimisim because for me what I see with this work in particular is learning not only about the process one may go through in doing it, but it also creates more questions as the work unfolds. Maybe there is something yet to be gleamed from this and I haven't thought of it yet. And though you and others say this has been done before we have to realize that earthquakes are still random events and as time goes along patterns change all the time.

Though the behavior of volcanoes for instance differs from earthquake patterns I think one can see that they may have a particular behavior for a long period of time and then it changes to something else. We should remember how things were 20 or 30 years ago when they talked about the San Andreas Fault in Southern, CA and the "Big One." In this matter the word "over-due" was heavily used and yet it hasn't given up the big kahuna yet. Instead other large quakes have happened elsewhere and people in those other places have had their worlds turned upside down unexpectedly, especially in regard to Northridge with its blind thrust fault.

I think its fair to say that one should not assume in regard to earthquakes there is a pattern which is constant and never changing. But I do think as you have been round the fence post for a while you must certainly recognize some patterns in certain areas during some time periods. I'm fairly certain if I can see these, they should be easily apparent to a professional.

Your response to the above questions would be appreciated.

Petra