John,

As you know a 6.0 earthquake is not a large earthquake so in his including it I'm not sure it is appropriate. Insofar as I am aware there wasn't anything going on at or near Parkfield before the earthquake struck. That is what makes it rather curious. In the past when there have been 4.0 earthquakes or a noticeable increase in seismic activity, nothing happened. And that was the case for 38 years, on-off, on-off and then finally it took place. If there was a serious increase in strain the meters would have all picked it up, but they didn't. There isn't anymore information from before that earthquake or after which will be of use 11 to 38 years from now. So I don't agree with his conclusion insofar as Parkfield is concerned.

However, Loma Prieta is a whole different matter and it was down-graded to a 6.9, but I guess he didn't note that. We did have two 5.0 earthquakes months before Loma Prieta and that's what prompted the USGS - Menlo Park branch to issue their alert. Though that was quite sometime before the earthquake happened and was mostly forgotten.

I think Korneev needs more earthquakes for his research before he'll have enough data to reach a learned conclusion. And when he says "large earthquakes" he needs to find some large earthquakes; rather than moderate one's. Or change the term "large" to "moderate". If he did that then he could include all of the 4.0 or greater earthquakes along the SAF and see what the results might reveal. It could be more interesting than just these two. I wonder what he would think about the Mettler 5.1, just off the SAF? Did it occur because stress is accumulating along the SAF and so it took a sidestep? Could be. Perhaps like Coalinga and Avenal are in relationship to Parkfield.

So many questions...

Petra