Swarms like that are fairly common in the Imperial Valley. It is, after all, developing ocean floor at the north end of the Gulf of California, and would be under water now if the Colorado River (before dams) had not build a big delta to keep it out. Because of the swarm's location at the south end of the San Andreas, where it "steps over" to the more-recently-active Imperial Fault, Big One chances were ramped up a tad for a few days, but have since subsided to background levels (e.g. it could happen any time, but we don't have reason to believe it WILL happen in the next day or 2). And the San Bernardino City Hall was evacuated for a couple of days just in case (it's seismically unsafe). Basically, last week's news.

Great photo, though!

And I do like Chile Colorado burritos...