You can see we were getting over a dozen earthquakes a day, in the mid-three range before the M4.2 earthquake, then it all stopped for a while. It's just starting now with an M2.8. Over the next few days it will increase until the next frenzy, and finally a large event or events.
This last earthquake was unusual in it's very small felt area. Even the few higher intensities are probably brick houses that are falling apart from all the other earthquakes. This earthquake didn't even get any press, smaller earthquakes have made much more of an 'impact'. For this reason, I can't decide whether it was shallow or deep. Right now I'm leaning towards deep. Remember that the 'official' depths are meaningless, with large error bands. You really need top-notch equipment right on top of the earthquake to get depths. I also suspect they are installing single-channel, high-frequency garbage.
Although the usgus has made a big deal about Paleozoic faults, the physics must concentrate on the Precambrian fault system which is a completely different animal. Those poor Californians wouldn't recognize physics if it hit them in the face.
California is a land of weak rock and stress accumulation from plate motion. The Deluded refer to faults as 'storing energy'. They don't, they just move with the tiniest amount of stress. The OK mechanism is completely opposite - strong faults in high stress, and is a mechanism of stress relief.
-to be continued (maybe). The dog wants a walk, and I have the attention span of a two-year old.
Made it to 6 parts! Biggest ever!
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