Chris, I can not bring up the EQ search for now, which I depend on for scientific proof for a seismicty finding. My personal sense based on shake intensity over 45 years is that all of So Cal is in a definite lull since Hector Mine. The last quake I felt was Anza 5.2 on 06/12/05. I have not fully studied the rhyolitic domes down near the Brawley seismic zone. It appears that there is a disassociation between the domes and surrounding faults that are seismically active. I have not been able to draw the conclusion as yet, but remember, my knowledge base is not focused on that geologic formation. Obsidian Butte quakes "seem" to activate on a different time line than surrounding fault structures. What I mean by that is Imperial can have increased seismicity, but it does not express in the domes. Obsidian Butte can have a large swarm and it does not express on other faults in a significant way.

My best guess is that the Obsidian Butte micros at 2 Km are not indicative of larger tectonic seismicity associated with deeper divergent or transform fault structures. We can not discount the possibility that Brawley could become a clash of giants, though.

Glen