4.6 Earthquake in Chatsworth

According to the U.S. Geological Service (USGS), there was a magnitude 4.6 earthquake on August 9th, 2007, at 12:58:49 am. The epicenter is recorded at 34.3 N 118.62 W (just north of Chatsworth, CA) at a depth of 7.5 kilometers. Since I live at roughly 34.46 N 123.17 W, this put the epicenter roughly 14 1/2 miles away from my house (surface point to subsurface epicenter).

Now I'm a pretty heavy sleeper, but this one did wake me up. My wife is a pretty light sleeper, but it barely woke her up -- she must have been really tired. The last time we were awoken with an earthquake in the middle of the night, my wife was in a state of near-panic and was awake for the rest of the night. This time, however, we both woke up and went right back to sleep. I recall that my first impression upon waking was that there was either a large truck rumbling down the street, the kids had dropped something large, or there was a bomb that had gone off somewhere in the distance.

In any case, my wife says she suggested it was an earthquake at the time and I just grunted and went back to sleep. What I remember was waking up and asking, "What was that?" then grunting and rolling back to sleep. At least the latter half of the story matches between us.

In any case, I don't get too disturbed about earthquakes. They're just not a big fear of mine. My take is that unless it's big enough to start knocking stuff off shelves, it's not worth getting excited over. And if it is big like that, my philosophy is simple, but maddening to my wife: try not to die and move on with your life.

At this point, you might be scratching your head about the "bomb" part from the second paragraph, and how I could possibly go back to sleep so easily if that was a possibility that had run through my head. You see, I grew up in Tooele, UT, where there's a big munitions dump nearby. While I was growing up, there would regularly be big explosions that would rock the town -- rattling windows, causing car alarms to begin to blare, and the like. In the mid-80s, the U.S. Army had to detonate these old bombs and such as a means of safely disposing of them in response to the disarmament agreements with the Soviet Union. So, weirdly enough, explosions in the distance don't even phase me. And if they don't bother me, then why would I get all uptight about a little shaking caused by a little earthquake?