Magnitude 6.0 Quake Hits Northern California, Causing Injuries and Outages 135
As numerous sources report, an earthquake of magnitude 6.0 struck California early Sunday morning, with an epicenter about 9 miles south of Napa. According to the San Francisco Chronicle's account, Some power lines down in western Contra Costa County, but Bay Area bridges appeared to be fine, according to the California Highway Patrol. There were widespread reports of power outages, gas leaks and flooding in the North Bay, with at least 15,000 Pacific Gas and Electric Co. customers without power in Vallejo, Napa, Rohnert Park, Santa Rosa and Sonoma. Police reminded motorists to stop at darkened intersections. ... In Benicia, several miles from the epicenter, the quake was strong enough to knock pictures off mantles.
Bay Area bridges appear to have survived the quake -- significant, in that the L.A. Times reports that USGS estimates peg it as "the largest earthquake to strike the Bay Area since the Loma Prieta temblor of 1989," and says that injury reports (especially from glass) are streaming in from the area around Napa. The Times also has a larger estimate of customers suffering power outages: "more than 42,000" around the northern Bay Area. Unsurprisingly, social media channels are full of pictures showing some of the damage.
For those in California, did you feel the quake? (And from how far away?) Update: 08/24 13:15 GMT by T : Also in earthquake news: an even stronger quake (magnitude 6.4) on Saturday struck central Chile, shaking Santiago -- nearly 70 miles from the epicenter -- for more than half a minute, but with "no immediate reports of fatalities or serious damage."
For those in California, did you feel the quake? (And from how far away?) Update: 08/24 13:15 GMT by T : Also in earthquake news: an even stronger quake (magnitude 6.4) on Saturday struck central Chile, shaking Santiago -- nearly 70 miles from the epicenter -- for more than half a minute, but with "no immediate reports of fatalities or serious damage."
Not strong in Oakland (Score:3)
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Why do Californians think they can "feel" the strength of a quake?
With the Northridge quake of '94 I was over 150 miles away and knew it was significant. Not by the rolling sensation, but by the duration.
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Because you can feel the relative strength where you are. Also, you start to get a feel for how far away it is based on the motion. Close ones rock'n'roll at the same time, while further ones get a jolt or two followed by a rolling motion.
It's part of the SoCal culture/tradition, so Independence Day had it right.
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The magnitude of a quake is the total energy released at the epicenter, and it's true that you can't estimate the magnitude from feel since you have no idea of the distance. But the intensity [usgs.gov] is the amount of shaking at a particular location, and is probably what bazmonkey was talking about.
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Maybe he wasn't talking about Mercalli, but I'm pretty sure he was talking about intensity and not magnitude.
Re: Not strong in Oakland (Score:2)
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You absolutely can feel the strength of the shaking at your location. For reference though, the USGS says it was around a magnitude 4 in oakland (and 6 at the epicentre)
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I think they're overstating it, but...different locations, even close together, can feel very different. I didn't quite sleep through it, but close. I wasn't even sure it was an earthquake. Still, I'd have guessed that it was around 3 at my location...and that's a factor of 10 difference.
OTOH, we also didn't get any damage from Loma Prieta, where other places nearby did, O my did they. So it depends a lot on your subsurface.
Bigger quakes are longer. (Score:4, Interesting)
"Why do Californians think they can "feel" the strength of a quake? It's complete nonsense because you cannot feel its distance."
It's not nonsense at all. Bigger quakes last longer. The duration of the shaking is a good measure of the actual strength, and can be read directly off the seismographs, while more accurate estimates take a while to compute from these and other measurements.
That's why you see initial estimates as "duration magnitude [wikipedia.org]", later revised to "moment magnitude" which more accurately measures the energy from measurements of the distortion of the underground structures due to the stress changes. You'll notice that it's SO good that the adjustment is usually only a couple tenths of a scale point - less than a 2:1 difference in energy.
The rip starts at some point along the fault and propagates along it in fits and starts, much slower than the compression and shear waves from the individual releases, as the motion from the relaxing stresses in the section that let go increases stresses in the next section. This keeps up until the effect reaches a point where the stress isn't enough (at the time) to make it let go. (You get aftershocks when the more gradual readjustments add "straw to the camel's back" and get it going again - or start one on another nearby section or another nearby fault.)
The strength of the wave decays with distance. But the duration increases as the wave takes multiple paths, scattering off underground structure. So a distant earthquake doesn't "feel" shorter than a nearby one. Longer-but-weaker. Also, the P wave propagates much faster than the S wave, is weaker, and doesn't "stretch out in time" much at all. Time separation is greater with distance. They feel very different. (Mnemonic: First the P wave makes you pee, then the S wave ...) So with enough experience one could ballpark both the strength and the distance from the feel of the quake.
For instance: Loma Prieta, a 7.1 moment magnitude (6.9 early duration magnitude estimates), propagated along aobut 22 miles of fault. It lasted 8 seconds, though as you got farther away the shaking got up to 45 seconds before it became too weak to be noticed. I was standing in front of Palo Alto City Hall when it got there, and my perception was first (P wave) "a truck is going over this overpass - wait', I'm not ON an overpass", then (S wave) "being in an airplane experiencing 15 seconds of mild turbulence." (Most ground-bound constructions {except for mobile and modular homes, which are built to be shipped on highways}, weren't built to withstand "15 seconds of mild turbulence". B-b ) I was listening to a San Francisco radio station: Seconds after the shaking started, the announcers got in two sentences (first about feeling an earthquake (P wave), then that it felt big (start of S wave)) before the transmitter failed (a bit into the S wave) - and the shaking was far from over.
The scale is logarithmic base 10, so a 1 point difference in scale is a 10x difference in energy, and thus time. This makes it EASY to guess the magnitude (if your sense of time doesn't distort to much from the excitement). A 6.1 would be 1/10th the energy of Loma P., so also about 1/10th the time, and Nappa to Oakland is comparable to Loma Prieta to Palo Alto, so call it a second and a half of the strong shaking.
On the other hand, for the first quake I felt after moving to CA I was nearly on top of a small one. (I think it was a high 2.x or a low 3.x.) Very sharp single shock - like a car hitting a concrete building while you're inside - followed by "echoes" as the wave moves on rapidly and EVERY building makes the sound of being hit (followed by a chorus of car alarms - shock sensors were common then). Sensation: Being in an elevator when it hit a misaligned section of the guide track. Three-stage perceptual distortion, as I realized that I was standing on the ground and my brain momentarily remapped my mo
Re:Not strong in Oakland (Score:4, Funny)
Any reports of chemical leaks at area meth refineries?
In the south bay... (Score:3)
It was strong enough to wake us up, but not enough to do any damage in Sunnyvale.
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We are 29 miles away and it felt stronger than any others I've been through in this same location - but still not very strong. However, my parents live in Napa - trying to contact them now.
Use text messaging.
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It was strong enough to wake us up, but not enough to do any damage in Sunnyvale.
Weird, I'm a 30 miles south of you and have several things come down. I woke up as well but didn't link the noise to an earthquake.
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Don't worry, your turn is coming when the New Madrid fault line goes to shit and suddenly the Mississippi river turns you and Mississippi into an underwater Atlantis.
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I think the last time the New Madrid fault went the estimate of the strength was over 9. You might not be there to enjoy the new beachfront.
OTOH, that fault doesn't go very often. You might be lucky for the rest of this century. But the longer it waits, the stronger the quake. (I'm hoping that slips along parallel faults nearby have defused the Hayward fault, but nobody know for sure.) The New Madrid is one that doesn't have that kind of pressure relief available. And it tends to lock in place while p
6 of one....half dozen of another... (Score:2)
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I am just a bit north of you in Mountain View and it was violent enough for long enough that smaller objects fell (nick knacks, candles).
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Local ground conditions are extremely important in fault shaking transmission. It sounds like it was a lot stronger where you were that is was where I live in Oakland, though perhaps other places in Oakland felt more of a shock.
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I'm in Sunnyvale and I was awake at the time. I could feel it [for 3-4 seconds], but nothing fell. Dining room light hanging from ceiling swayed. Feeling here was less than a 4.3 in Carmel when I was in Cupertino. I've felt worse before. I was shocked to learn it was a 6.0 up north [And I hope the severely injured people recover quickly].
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It wasn't enough to wake us up, here in the middle of the San Joaquin Valley (about halfway between Modesto and Fresno on 99, where I am).
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Dear moderators, this should be +1, Informative, not -1, Troll, thanks. It wasn't an insulting most, merely a statement of fact.
What about Chile? (Score:1)
Considering this happened before and was stronger, shouldnt this be here 1st?
Clearly the people of Chile didnt have the time to take pictures and update their twitter pages, so its not newsworthy?
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Considering that one of these was felt in the heart of the tech world, and this is a website about tech... No.
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Don't you mean the groin of the tech world?
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It's California. We don't get out of bed unless it's at least a 6.5.
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The Chilean quake was stronger but it was also deeper. ... the maximum intensity at the surface was less.
Also it was farther from large, internet-connected, population centers.
Just hope (Score:2)
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6 is a bit strong for a foreshock, isn't it? I'm not quite sure.
Clearly it means the stress has shifted to another part of the fault, but is there any reason to believe that the next stress point will be as energetic? The fault I really worry about is the Hayward fault.
Report from SJC (Score:2, Interesting)
It woke me up.
IMO a 6.0 in the Bay Area should go down almost unnoticed (like it does in prepared countries like Japan), instead of creating outages, floods, etc...
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Oh come on. one power line down, and other than that basically no damage. It pretty much has gone unnoticed.
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I don't know, I hear that Zeus is a heavy user of Google maps for pinpointing lighting bolt strikes.
Not sure about all the other gods, however.
Join the Quake catcher network of Stanford (Score:5, Interesting)
Join the Quake catcher network of Stanford. You can order a sensor, but your laptop can detect them too.
http://qcn.stanford.edu/ [stanford.edu]
The detected earthquake
http://qcn.stanford.edu/earthq... [stanford.edu]
Bert
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I have a QCN sensor. It's interesting to see the live graphed accelerametor data, but a USGS NetQuake rates significantly higher on the awesome scale. Robust, self contained setup with battery backup.
Predicted casualties / damage (Score:3)
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Santiago (Score:4, Informative)
I am currently working in Santiago and did feel last nights shaking. It is not the first I have felt in the last year but it is definately the strongest. I haven't heard of any problems in Santiago but Valpariso is much closer and a portion of the city was recently damaged in a large fire so this might complicate the recovery efforts there.
Iceland is also moving - Bárðarbunga Vol (Score:3)
http://earthquake.usgs.gov/ear... [usgs.gov]
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It's strange . . . we're worried about dying from Global Warming . . . getting hit by an asteroid . . . an Ebola epidemic . . . but nobody seems concerned that maybe the Earth could bust apart at its seems.
I, for one, would welcome the end of the Earth in some weird way that we never thought about.
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The amount of energy required to overcome not just the physical bonds of stone but the gravity of the mass of the earth
Yes, but is it stronger than emo angst? Queenish drama is immune to gravity wells.
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. . . but nobody seems concerned that maybe the Earth could bust apart at its seems.
Seams okay to me.
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You're kidding, right?
Just after people's terror of word-ending asteroids wore off, the media was pushing the Yellowstone Supervolcano (very hard) as the thing we should all be pissing our pants about. And they really never gave-up on it, either:
http://www.inquisitr.com/10848... [inquisitr.com]
http://www.bbc.com/news/scienc... [bbc.com]
http://www. [cnn.com]
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The Yellowstone Supervolcano wouldn't split the Earth apart at its seams any more than any of the other reasonable scenarios would. Even the collision that created the moon didn't do that. It might, however, kill off most people in the North American continent. And solve global warming at the same time.
The thing is, there's no real way to predict when, or if, it will go off again. There's some magma filling chambers under it, which has some people worried, but nobody knows whether or not its really sign
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A gigantic crater with lava flowing through it, will look an awful lot like something "split the Earth apart" to most people.
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We're worried about 90% of life on Earth becoming unsustainable as a result of global warming.
No we're not - we have fossil records from, e.g. the Jurassic where high temperatures and CO2 at about 1300ppm resulted in mega- flora and fauna all around the earth, even in areas that have desertified as the Earth's moisture has become locked up in Antarctic ice sheets over the past several hundred years of cooling (as evidenced by ancient Chinese maps).
What "we" are worried about is the rich cultural and politic
WELL said. (Score:2)
What "we" are worried about is the rich cultural and political elite losing their seaside mansions ...
Well said, sir. (I already commented in the article so couldn't mod that up. I had to settle for "friend"ing you. B-) )
Also: In the spirit of "Never letting a crisis go to waste", it's also an opportunity for the 1% to incrase their power over the 99%, and find ways to rip them off. (Carbon taxes. Government mandated carbon credit exchange schemes, with markets [nationalreview.com] provided, and billions in transaction fe
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No, most life on earth will survive any reasonable global warming scenario. Civilization surviving is much less certain. So while it wouldn't directly kill us, it might result, indirectly, in 90% of humanity dying. Not, repeat, *not* 90% of life on Earth...unless it resulted in all-out warfare between the mega-powers. All-out nuclear warfare could do that, I suppose.
outer Richmond district San francisco (Score:1)
It felt strong here, woke everyone up and we got the kids away from windows. This 1920s house may amplify things. Going to see if the cracks in the walls have grown.
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Nothing to see here, move along... (Score:2)
I guarantee you will feel a 3.0. . . (Score:2)
. . . if you're close enough to the epicenter. It is enough to rattle the china. It's all about the inverse square law. There are small Earthquakes in California all the time, but most of them are too far away. California's crust is too fractured to transmit earthquake energy very far.
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I did feel the earthquake on the south side of San Jose, but it didn't get me out of bed. Felt like the house was shaking for a bit, but nothing got knocked over. (And yes, we have plenty of things in the house that could get knocked over quite easily.)
Meh, didn't even really notice (Score:1)
Down in the city I woke up to feeling the quake, but honestly it didn't feel very severe so I went back to sleep.
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East Bay / North Bay... (Score:2)
Didn't even get woke up near Discovery Bay. Probably a shdaow effect of Mt. Diablo's mass...
Family member up in Pinole had some light damage. Things knocked out of cabinets, and ceramic planter pots sitting on concrete broken.
Middle of San Francisco (Eureka Valley) (Score:1)
I woke up a few minutes before and was just getting back to sleep when it happened. It was a long quake, a good 15 second at least. The room shook side to side with a rough swaying. I started slow (like a big truck driving by the house), ramped up really quickly, held that for most of the time, then damped out.
All Lego displays remained intact.
Napa Valley (Score:3)
I wonder how the wineries made out. I toured a few of them a couple of years ago. At one place, they had their barrels stacked and kept from rolling only with wooden wedges tapped into place between them. I asked the guide if that was a problem during earthquakes. His response was, "We never get earthquakes here."
Felt in Lake Co. (53mi. N of Napa) (Score:2)
Woke my wife and I up, large rolling motions, audible shaking but nothing fell down. Enough to get our attention, for sure! Funny thing is, first thing we did after everything stopped (we ran to our sons' room and stayed there for a few minutes, it didn't wake them up) and we knew that was the bulk of it, was to grab our cell phones. Wife went on Facebook for reports from people in the area, and I downloaded an Earthquake app. Funny how Facebook is the first place most people went to read about it.
50 miles northwest (Score:1)
San Francisco (Score:2)
I woke up to go pee, felt the earth shaking as I was walking to the door, went pee, went back to bed, and I hoped the epicenter was fairly close, because otherwise a lot of people were going to have a bad night.
It was not a big earthquake by any means, but I see it did some real damage near the epicenter up in American Canyon.
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Was strong enough to wake me up in San Francisco too, but not strong enough to bring anything down. There are some maps from the USGS that shows that it was a lot stronger in American Canyon than it was here.
http://earthquake.usgs.gov/ear... [usgs.gov]
http://earthquake.usgs.gov/ear... [usgs.gov]
LA Times wins for sensationalism (Score:2)
There's no link in the summary, and I'm not going to bother hunting down TFA.
The bridges surviving a 6.0 is hardly noteworthy; 6.0 just isn't that big a quake by local standards.
The only thing that can be inferred from this being the "largest since Loma Prieta" is that is has been eerily quiet since then. It makes sense, that let a lot of stress out of the local fault systems, but when I was growing up, you didn't even talk about a 5.0.
Strongly Felt Here (Score:2)
I'm in Northern Contra Costa county about 12 miles from the epicenter and felt it strongly here. The shaking lasted about 11 seconds and was pretty intense.
No damage here, as we have everything secured and the house is designed to withstand a much larger quake.
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It was felt relatively strongly here in Walnut Creek (also CC county, about 25 miles from the epicenter). I've lived in CA my whole life (over 30 years) and it's definitely one of the longer quakes that I remember. Fortunately no damage here, just a couple scared dogs. My brother in west Berkeley slept through it, but I'm guessing it's because he's on a different fualt line.
San Rafael (Score:2)
South Bay (Score:1)
Not really "Bay Area" (Score:4, Informative)
The quake was in Napa, which most people don't consider to be the Bay Area. Yes, it's nearby, but it's not really the Bay Area.
When the headlines read "Massive Quake Hits Bay Area!", most people will think of places like San Francisco and Oakland. According to Google Maps, Oakland to Napa County Airport (near the epicenter) is 37 miles and my guess is 30 miles in a straight line.
See that map here: http://www.google.org/publical... [google.org]
In my part of Oakland, it was big enough to wake me up, but nothing rattled or hit the floor.
Napa got hammered, but the Bay Area just got its dishes rattled.
I saw a bunch of panic on social media this morning, from people out of the area. All they saw was "Bay Area Earthquake" in the media.
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And when headlines read "Southern California" most people think of Los Angeles...
Why should headlines cater to stupid people?
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People outside the Bay Area think of it as the Bay Area.
People inside the Bay Area don't need to be told that they are in an area where an earthquake just occurred.
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People outside the Bay Area think of it as the Bay Area.
People inside the Bay Area don't need to be told that they are in an area where an earthquake just occurred.
A better headline uses the phrase "Northern California". Causing unnecessary panic and fear by calling it in the wrong (but more highly populated) area is just lazy, sensationalist journalism.
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"Causing unnecessary panic and fear by calling it in the wrong (but more highly populated) area is just lazy, sensationalist journalism."
It's much better to cause unnecessary fear and panic in Redding and Yreka, as opposed to places *where they actually felt the earthquake*.
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I guess it is. After 12 to 24 hours, the press stopped saying "Bay Area" and switched to "Northern California".
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Napa would be considered Bay Area. Even Santa Rosa, northwest of there, is often thought of as "Northern Bay Area."
Brick houses in earthquake zones (Score:2)
M. 6 quakes (Score:1)
Are not that rare. They happen several times a month somewhere on the Earth. Seismicity is subject to selective attention. When quakes, most of them, occur far from population centers no one except geologists notices, and so ordinary people are apt to make false inferences about quakes that occur together in time. I am not saying that theire are no connections, only that the scientific claim requires some mechanism to link them.
I live on the San Francisco Peninsula and did feel the quake. The Initial com