I edited my post from yesterday to take out the critique I made of the PBS show on Simon Winchester's quest to write about the 1906 San Francisco earthquake, since it didn't really belong there. I'll put it here instead...
My point was that I kept getting irritated by how his sense of self-importance was blinding him to both scientific facts and the more meaningful thematic lessons from the quake. No, Mt. Diablo isn't the highest peak in the Bay Area; Mt. Hamilton is. And the 1868 quake wasn't on the San Andreas Fault, it was on the Hayward Fault. Plus if you want to talk about historical hubris of building major cities on sites of major quakes, it's much more profound to look at, say, a city like Memphis built along the Mississippi in the wake of the much more major New Madrid quake of the 19th century.
Anyway, it turned out to be apropos that I wrote that yesterday, because this morning around 4:40am the Bay Area was awakened by a 4.2 earthquake on the Hayward Fault.
The Hayward Fault is a Bay Area fault line, but it runs under Oakland, not San Francisco. Winchester knew about the Hayward fault because he went out to a site where he could observe the creep (the land on one side of it is sliding past the other), but he kept focusing on San Francisco, San Francisco, San Francisco, as if nothing else existed beyond it.
When it comes to fault lines and quakes, it's never so local. The consequences will usually be most severe at the epicenter, but the stronger quakes can be felt miles away. In 1989 the quake was centered between San Jose and Santa Cruz, yet there was major destruction miles to the north.
This one last night was pretty minor. Even for people right on top of it there was little damage apart from a few broken windows and some spilled wine. I could feel it out on the boat, since we can feel them when we're sitting on the mud. It shook the bed for a few moments, but was over pretty quick. I always wonder when I feel them where and how big they were. What I felt last night was fairly minor, almost fun. It obviously wasn't causing any harm here with the shaking, but it's hard to enjoy the ride if you're not sure what's going on closer to the center. A small earthquake that's close will lead to minor shaking, but so will a big one that's farther away. At four in the morning you wonder which one it will be that you'll wake up to.