aftershock - SFist - San Francisco News, Restaurants, Events, & Sports

Aftershocks Rattled The Bay Area For Hours Monday Morning

Eve Batey — Mon, 17 Aug 2015 13:00:00 GMT

That 4.0 magnitude earthquake rattled us out of bed at 6:49 this morning might have been the biggest bang of the day (we hope!), but that doesn't mean the Hayward Fault stayed quiet after that. In fact, things kept on shaking until about 8:30, just at a much lower level.

According to the US Geological Survey, the same spot near Piedmont that shook this morning has experienced seven additional aftershocks of note, from a 1.6 at 6:52 to the last, a 1.2 at 8:28. The strongest appeared to be a 2.4 at 7:40, which was apparently felt by around 81 people.

The M4.0 this AM released 1/30,000 the energy of the 1989 M6.9.
— Dr. Lucy Jones (@DrLucyJones) August 17, 2015

Of course, what everyone wants to know is if this morning's quake is a sign that something bigger is on the way. The answer? Probably not, but who the hell knows?

“At the moment," USGS geologist David Schwartz tells KQED, "it’s hard to say that this had any greater meaning than we’ve had earthquakes in this general area before.”

Keith Knudsen, Deputy Director of the USGS’s Earthquake Science Center in Menlo Park is a little more comforting. He tells the Chron that “There is a low likelihood that this could be a foreshock. There is a 5-to-10 percent chance that we could have a bigger earthquake in the coming weeks.”

The 6:49 a.m. quake didn't cause any major damage — some folks said things fell off shelves, and the Chron reports that "At least one traffic light at Geary and 20th streets in the Richmond District toppled over" (but maybe that was just pee) — but it felt strong to many. That's because, Knudsen says, “It was relatively shallow and intense for a magnitude 4...People near the epicenter felt more intense than they would if it was deeper.”

All in all, the USGS estimates, about 40,000 people felt a strong jolt and 510,000 felt a moderate rattle in this morning's largest quake. 4.5 million people probably felt weak or light shaking.

And it wasn't just people: though my animals didn't notice a damn thing (they never do!), at least two Bay Area dogs did. Check it out:

Previously: 4.0 Magnitude Earthquake Gets The Bay Area's Monday Going

3.7 Aftershock

Brock Keeling — Wed, 31 Oct 2007 16:03:52 GMT

Wendy Tokuda looked mighty concerned and had the gall to interrupt Judge Judy just now, so:

A 3.7 aftershock in San Jose just shook the ground of Silicon Valley. According to our own Spencer Williams, it happened a little before 4 p.m. and It "only lasted a couple of seconds." So there you have it.

We'll ~~run it into the ground~~ update if there's more to report.

For more info on today's aftershock, go here.

Whew, That Was Fun

Matt Baume — Tue, 30 Oct 2007 20:05:55 GMT

9:30 Update: Things seem to be settling down. We're going to move the bulk of this post behind a jump. The only really big news at the moment is that there's a 30% chance of a strong aftershock in the next week, and a 5 to 10% chance of another strong earthquake.

If you were lucky enough to feel The Great San Francisco San Jose Alum Rock 5.6 Back-and-Forthing of 2007, please continue to send in reports. We especially like links to blog posts about the earthquake, such as Greg's.

Finally, a headline's gone up on KRON's site; but the headline links to a story about the Berkeley tree sitters. Ha! Hey, we wonder if they got rattled out of their perch? Macherena reports that KRON's just been showing a static shot of a seismograph. Bet it sure would be handy to have a reporting staff right about now.

9:10 Update: Cranky reports that MTV is showing reruns of A Shot at Love with Tila Tequila.

Regarding aftershocks, the USGS says:

... the probability of a strong and possibly damaging aftershock IN THE NEXT 7 DAYS is approximately 30 PERCENT. ... there is a small chance (APPROXIMATELY 5 TO 10 PERCENT) of an earthquake equal to or larger than this mainshock in the next 7 days. ... approximately 15 to 40 SMALL AFTERSHOCKS are expected in the same 7-DAY PERIOD ...

So there.

Here's where some of the aftershocks have landed -- as you can see, they're pretty small:

BART's running its trains slowly, but with no apparent problems; PG&E reports no utility disruptions. Some broken water pipes reported near San Jose.