Just a few days after a 4.4 magnitude earthquake hit the San Jose area, a second cluster of quakes has rattled the South Bay, the United States Geological Survey reported this morning.

Things began at 4:13 a.m., the USGS says, with a 3.0 magnitude earthquake with an epicenter about 4.5 miles from the South Bay city of Gilroy. It had a depth of about 3.1 miles.

The second earthquake struck about 20 minutes later, at 4:32. It clocked in at a 2.6 magnitude, the USGS says, with a depth of 3.16 miles and a different epicenter than the first, with this one located 5.5 miles from Gilroy.

No damage was reported in the quakes, the second this week following Monday's San Jose temblor. Unlike that quake, which was felt as far north as San Francisco, the shaking was barely felt outside the area, with most respondent reporting "weak" shaking on the USGS's Did You Feel It? map as of publication time.

Previously: Armageddon Yet? 4.4M Earthquake Strikes San Jose

As if this day couldn't get any more dramatic for the Bay Area, a modest — but detectable in San Francisco — tremor just rocked the South Bay, centered at Alum Rock, 12 miles east of San Jose. According to the USGS, it was a 4.4M quake — the epicenter appears very close to one that struck along the Hayward Fault almost exactly a month ago.

The quake struck at 5:53 p.m., and ABC 7 reports there were no immediate reports of injuries.

I felt it in central San Francisco, and Twitterers felt it as well.

Clearly some of these people don't have the same end-of-days feelings that I have had all day writing about the fires to our north, which are currently 0% contained, and have claimed 10 lives that we know of so far.

In yet another example of how America can't seem to fund projects that are actually important or finish them in any reasonable amount of time, the West Coast earthquake warning system known as ShakeAlert, in the works since 2006, still has a long way to go before completion. Back in 2013 we discussed here how the system remained pathetic in comparison to others in Japan and Mexico — which just experienced two major earthquakes in the last two weeks (and did you see those videos of buildings collapsing in Mexico City?!?). Fast-forward to 2017, and we learn via NBC Bay Area that ShakeAlert still needs $38.3 million to finish building out its system of monitoring stations — 750 out of a necessary 1,675 total stations have been installed so far along the West Coast, with about 250 of those in the Bay Area — and it will need to fund an annual maintenance budget of $16 million going forward, once it's done.

That is a lot of money, especially considering the last federal funding we heard about in 2015 was just $8.3 million, approved by Congress. To date, about $26.4 million has been allocated to the ShakeAlert project, though it's unclear why after 11 years it would remain only 50 percent complete.

Seriously. What is taking so long?

An early warning system already in place in Japan in 2011 gave residents there warning of the major earthquake that struck in March 2011.

The ShakeAlert technology is expected to be rolled out in California schools in 2018, as NBC Bay Area reports, and "While the system remains in the testing phase, BART, PG&E and LA Metro already use the program to quickly shut off services in the event of an earthquake." Ultimately, ShakeAlert will be able to send alerts to everyone's cellphones, and even their computers, warning them of shaking anywhere from a few seconds to over a minute before it starts, potentially saving many lives.

And, as we all should know well after reports every time we get a tremor here, the Bay Area is DUE for a major earthquake, with the USGS predicting we will get a 6.0M or above in the next 30 years, with 98 percent certainty — and FYI, they've been saying that for well over 10 years.

Here, a chart from NBC Bay Area, via USGS data, showing just how quiet the earthquake activity has been here since 1906, relatively.

A video below from two years back explains how the ShakeAlert system will work once it's complete — and it touts how test users in San Francisco got an alert on their phones in 2014 eight seconds before the shaking from the Napa earthquake hit the city.

And if you don't have an earthquake kit yet, now is as good a time as any!!

Related: New Study Finds Hayward Fault Connected To Second Fault, Potentially Making An Earthquake Much Worse
Yes, All That Winter Rain May Be Triggering Earthquakes

A small earthquake shook part of the South and East Bays this morning at 10:32 a.m., and the USGS is saying it had a magnitude of 3.3 and was centered just north of Alum Rock, apparently along the Hayward Fault.

A similarly small quake on the Hayward Fault happened in Berkeley back in June.

Did you feel it? KTVU's Maureen Naylor did, and she posted a video of a window shade cord swaying, so, yeah, pretty small.

Others reported it lasted about three to four seconds.

Let this serve as yet another helpful reminder to get an earthquake kit together! Our pals at LAist just put together a fast and dirty guide to building one using Amazon Prime alone.

But people really need to stop posting stuff like this for a 3.3M.

If you felt a little rattled as you got ready for work this morning, you weren't alone: According to the US Geological Survey, that shaking you felt was an earthquake just off the San Francisco Coast.

According to the USGS, the 3.2 magnitude quake struck at 6:36 Tuesday morning off the San Francisco coast, with an epicenter just 6.8 miles northwest of the Zoo. It had a depth of three miles, the USGS says, and was located near the San Andreas Fault, according to CBS 5.

Local news outlets say that the shaking was felt across the area. According to KRON 4, "Viewers tell us they could feel rattling in San Francisco. Another viewer reported feeling a “strong jolt” in the inner Richmond District.

"Some people took to social media to report they felt shaking in places such as San Francisco and Pacifica," NBC Bay Area reports. "One person noted that the earthquake was 'short and sweet' while someone else reported feeling a jolt before a couple seconds of rattling."

Stephanie Recob of Daly City told the Chron that she felt “a jolt and then a few seconds of rattling in Daly City.”

According to the USGS's DidYou Feel It? map, the shaking was felt as far north as Novato, and as far south as Half Moon Bay.

No damage has been reported as a result of the earthquake, ABC 7 reports, and no tsunami warning has been issued. According to NBC, the San Francisco Fire Department says that so far, they haven't gotten any calls regarding the quake.

Update: The Chronicle reports via the USGS that a second quake of 2.7M struck an hour later at 7:32 a.m., with an epicenter a bit further north, 16 miles east of Shingletown in Shasta County.

Some residents of Monterey and San Benito counties got an early alarm clock this morning, when a 4.0 magnitude earthquake shook them awake.

According to the US Geological Survey, the earthquake struck at 3:55 this morning about two miles from the Monterey County burg of Aromas, five miles from San Juan Bautista, and 35 from San Jose. It had a depth of 3.6 miles and, according to the USGS' "Did You Feel It" map, was felt throughout Gilroy and Santa Cruz County.

No damage has been reported, nor was anyone injured in the quake.

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.

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

Scientists and KRON 4 are using Tuesday morning's tiny quake on the Hayward Fault as an excuse to remind us all that a big and potentially deadly earthquake is due "any day now," as has been discussed many times over the past twenty years. Just a couple months ago we had another unsettling reminder via a new report that focused on the possibility of two faults co-rupturing in the Bay Area.

We currently face a 95 percent chance of another Loma Prieta-sized (6.9M) quake in the next few years, with a strong likelihood of that quake coming from The Hayward Fault. There's a 76 percent chance of a much bigger quake of 7.0 or greater, and furthermore, the Hawyward Fault has two spots of possible co-rupture with another fault: the Rodgers Creek Fault in Napa to the north, and the Calavares Fault to the south.

The last time the Hayward Fault busted open was way back in 1868, causing what would be known for the ensuing few decades, until 1906, as The Great San Francisco Earthquake. That quake is believed to have been about Loma Prieta-sized, 6.8 or so, but caused a fair bit of damage to the then much less populated Bay Area. 30 people were killed in that "forgotten" quake, and obviously a new quake on the Hayward Fault would likely cause far more widespread damage than that one 147 years ago.

Scientists caution, though, that Tuesday's quake is no indication that a bigger quake is imminent. But, of course, that's not to say that foreshocks aren't a thing — and CalTech experts explain, "foreshocks cannot be positively identified as foreshocks until after the mainshock has occurred."

SO, once again, and I need to take this advice too: Get your earthquake kit together.

Related: More Frightening Talk About The Devastating Earthquake Likely Coming To The Pacific Northwest

Bit of a late start this AM, esp on Fremont line as we conduct track inspections due to minor quake. 15-20 minute delays systemwide.

— SFBART (@SFBART) July 21, 2015

BART's began service later than expected today, after an earthquake with a magnitude of 4.0 struck the Fremont area at 2:41 this morning.

According to the United States Geological Survey, the quake was in the Hayward Fault, and had a depth of 5 miles. It's epicenter was 2 miles north-northeast of Fremont, 2 miles east-southeast of Union City, and 7 miles southwest of Pleasanton.

At 4:12 a.m. Tuesday, BART sent an alert warning that due to the quake, they were delaying service to perform a track inspection. At 4:57 they determined that all tracks were fine, and service began for the day.

The USGS reports that there have also been two notable aftershocks in the same area this morning: a 2.7 at 2:56 this morning, and a 2.6 at 3:07. There have also been numerous smaller (less that a magnitude of 2) events all morning.

According to the USGS's "Did You Feel It?" map, the seismic event was felt throughout the Bay Area. However, at publication time no injuries or damage had been reported as a result of the quake.

Here in the Outer Sunset, I slept right through it. Did you feel it where you are? Tell the USGS, then tell us!

It's been a shaky few days in Concord, California, with a series of magnitude 3+ earthquakes hitting that area since Sunday. All based in the worrisome Concord Fault the latest was another 3.6 magnitude quake that struck at 7:32 this morning.

The 3.6 follows a 3.2 reported in the area at 7:01 this morning, says the US Geological Survey.

According to the USGS, the latest temblor's epicenter was the same as the the last several quakes felt in the area, including Sunday's 3.6 that was felt across the Bay Area.

This morning's quakes had a depth of 8.6 miles and were located a mile south-southwest of downtown Concord and 2 miles northeast of Pleasant Hill, the USGS reports.

Early results from the most recent quake on the USGS's "Did You Feel It?" map suggest that this morning's shaking wasn't felt much outside the immediate area. At publication time, no damages or injuries have been reported.

Did you feel the shaking where you are?

Previously: Concord Fault That Caused Sunday Quake Has Major Damage Potential
Whoa! 3.6 Magnitude Earthquake Shakes East Bay

According to the US Geological Survey, a 3.6 magnitude earthquake struck the Bay Area early this morning, shaking folks in San Francisco, down the peninsula, and as far north as Vacaville.

The quake struck at 12:06 a.m. Thursday, and had an epicenter about 1 mile northwest of San Ramon, with a depth of 6 miles.

3080 Bay Area residents stopped whatever it was they were doing at that hour long enough to let the USGS know they felt the quake, including 33 folks in San Francisco who reported they had been shaken.

The majority of the respondents were based in the East Bay, with thousands reporting feeling the "weak" to "light" quake.

“All of a sudden I know this sounds a little weird, I felt a little dizzy,” San Ramos resident Ross Butler told CBS5.

“And then all of a sudden, I saw my screen started moving back and forth. And I just sat there and I backed up off my chair … (it) lasted for 3 to 5 seconds.”

According to local officials, no damage has been reported as a result of the quake.

The well-worn phrase "it could be tomorrow, it could be years from now" is about the least comforting phrase there is to any Bay Area resident. But yet another study has come out reinforcing the idea of cyclical periods of seismic activity, and reminding us that yes, we are due for a Big One. Or Big Ones.

As reported in the journal Nature and in the Bulletin of the Seismological Society of America, new research looks at the period from 1600 to the present, using both existing records and geological evidence, and suggests that the Bay Area has seen two periods of violent seismic jolting in that time, with lengthy, 100+-year periods of "seismic quiet" in between. The first period was between 1690 and 1776, during which time a cluster of earthquakes rocked the region, and then things went pretty quiet right up until 1906.

This notion of there being 100-year great quakes, or something thereabouts, is not a new one, but this study is different in that it looks at paleoseismic evidence, i.e. evidence in rock and soil, in order to identify major seismic activity before records were being kept in this region. "The idea is that stress builds up, is released and builds up again," says US Geological Survey geologist David Schwartz, who led the study. That is, of course, something we've heard before.

But also new here is the idea that we could expect another extended period of repeated major jolts, as opposed to just one Big One. Looking at the evidence of that 86-year-period starting in 1690, the region seems to have had six large quakes ranging from 6.6 to 7.8 magnitude, on five different faults. A situation like that, where we had major quakes every five or ten years, would make projects like the new eastern span of the Bay Bridge laughable — since that took about 20 years too many to complete.

And for those would prefer the head-in-the-sand approach to this type of news, you'll be comforted to know that another researcher involved in the study is more cautious in giving credence to this paleoseismic stuff.

“Identifying something that looks like a pattern becomes very interesting because this behavior can be extrapolated into the future,” says Yuri Fialko, a geophysicist at the Scripps Institution of Oceanography in La Jolla, California, who was not involved in the study.

But Fialko warns the study does not prove definitively that the seismicity is cyclic. Palaeoseismic data can be unreliable or incomplete, as they are based on interpretations of displacement seen in layers of rock and soil. Historical records do not extend back far enough to demonstrate a cyclic trend.

Officially, per the U.S. Geological Survey, this remains the prediction:

There is a 63% chance of one or more magnitude 6.7 or larger quakes striking the Bay Area in the next 30 years.

Nonetheless, now is a good time for yet another nudging reminder that you should be pulling an earthquake kit together, if you haven't already. And you should probably check the dates on any canned goods you might have included in a kit you made 8 years ago, and replace the water. Because 8-year-old bottled water is not drinkable. You may, however, use it to fill your toilet or washing machine should that become necessary, and assuming the city doesn't burn to the ground again within 24 hours.

As we've tried to remind you before, after 1989's Loma Prieta quake, an estimated 12,000 Bay Area residents were displaced permanently or temporarily, and homes that remained intact had no water, electricity, or phone service for days. And we're due for a bigger one than that.

[Nature]
[WSJ]

Admit it. When a 4.4 magnitude earthquake rocked Los Angeles Monday morning, at least part of you wondered if that SoCal seismic activity might have an impact on us NorCal folks. Rest easy! According to at least one seismologist, the LA quake won't have any shaky results for those in the Bay Area.

David Oppenheimer, a seismologist with the U.S. Geological Survey, tells KCBS that “what happens in Southern California really doesn’t impact the state of stress in Northern California."

According to Oppenheimer, while large quakes relieve stress on global fault lines, they only do so locally. So while you might see a big quake on a fault line that runs all along the state, that doesn't mean you can expect activity at multiple points along that fault line.

Of course, that doesn't mean that we can't have a completely unrelated earthquake at any time! So let the LA quake be a solid reminder to make an emergency plan.

[KCBS]
[Ready.gov]

Did you feel it? A 3.4 quake shook San Ramon this morning. It happened at 9:30. No reports yet of any injuries.

This comes on the heels of a smaller quake that hit the area yesterday.

Another quake here in San Ramon today. 3.4 this time, so stronger than yesterday.

— Ken Bartrum (@bcxanth) November 13, 2013

We'll keep you updated as soon as we know more.

According to the US. Geological Survey and several Twitter updates, an earthquake rattled the Bay Area Sunday night at 9:26 pm. The minor tremor, according to SF Appeal, "had a magnitude of 3.1, and struck an area about 2 miles northeast of Berkeley, with a depth of about 4.6 miles at its epicenter."

No injuries were reported.

Folks from Twin Peaks, the Mission, and other SF neighborhoods claimed to have felt it. We, however, did not feel it in SoMa. Maybe that's because we were riveted by Homeland? Who's to say. But we didn't feel any shaking going on last night.

[SFGate]
[SF Appeal]