California
Related: About this forumBay Area: Creep in 4 faults means big quake may be poised to hit
Four highly stressed seismic faults in the Bay Areas densely populated San Andreas system are moving on the surface and could rupture in a major earthquake at any time, according to scientists tracking their movements.
The faults include the Calaveras, which runs roughly from Hollister (San Benito County) to Danville; the Hayward, between Suisun Bay and San Jose; the Rodgers Creek Fault in southern Sonoma County; and the Green Valley Fault near Richmond and Fremont.
The extent of fault creep controls the size and timing of large earthquakes, and measuring that creep rate helps tell us how much strain is building up on the faults underground although it cant tell us when a fault will rupture in a quake, said geophysicist James J. Lienkaemper of the U.S. Geological Survey in Menlo Park, who led the study.
SNIP
Lienkaemper and his colleagues said the Hayward Fault, long considered the most likely to rupture in the near future, could eventually trigger a magnitude 6.8 quake. The Calaveras Fault could also rupture with a magnitude of 6.8; the Rodgers Creek and the Green Valley faults could each yield a magnitude of 7.1.
MORE: http://www.sfgate.com/bayarea/article/The-Bay-Area-s-next-big-quake-could-be-on-any-5820259.php
Don't be fooled by your previous experiences with seismic activity. Having been through both Loma Prieta (6.9 magnitude) and the recent West Napa earthquakes (6.0), I can tell you the shaking from a 6.0 can be as strong, if not stronger, than a 6.9 should you live practically on top of it (the West Napa epicenter was 5 miles from my house).
A 6.8, should it happen under UC Berkeley or off the coast of San Francisco, is going to cause catastrophic damage. Get prepared now.
arcane1
(38,613 posts)Would we be at risk of a tsunami?
KamaAina
(78,249 posts)the San Andreas goes out to sea just before it would reach SF.
Auggie
(31,061 posts)At Daly City/Westlake, just south of San Francisco, the San Andreas Fault veers into the ocean. The city is not built directly on the fault but very close to it, so a 6.9 centered just off the coast is going to create major havoc.
The motion of Loma Prieta, while weakened over 60 miles, was still strong enough to liquify parts of San Francisco's Marina and cause highrises to sway several inches. I was in one of them.
The 1906 earthquake was centered just off the coast.
kestrel91316
(51,666 posts)not just directly atop it????
Wow.
arcane1
(38,613 posts)But please, be an asshole
On edit: I live in SF, I know how quakes work. Try reading my post next time.
Brother Buzz
(36,214 posts)Go Bruins!
An interesting but unsettling read: Marc Reisner's A Dangerous Place: California's Unsettling Fate
Writing with a signature command of his subject and with compelling resonance, Marc Reisner leads us through Californias improbable rise from a largely desert land to the most populated state in the nation, fueled by an economic engine more productive than all of Africa. Reisner believes that the success of this last great desert civilization hinges on Californias denial of its own inescapable fate: Both the Los Angeles and San Francisco Bay areas sit astride two of the most violently seismic zones on the planet. The earthquakes that have already rocked California were, according to Reisner, a mere prologue to a future cataclysm that will result in immense destruction. Concluding with a hypothetical but chillingly realistic description of what such a disaster would look like, A Dangerous Place mixes science, history, and cultural commentary in a haunting work of profound importance.
Auggie
(31,061 posts)Zorro
(15,691 posts)and it will make any citizen of California seriously consider relocating.
Cleita
(75,480 posts)claims their seismic studies show that there is nothing to worry about.
Brother Buzz
(36,214 posts)PG&E, in their infinite wisdom, wanted to build a nuclear reactor, not near, not on, but IN an active fault back in the early sixties.
The citizens of Sonoma and Marin county mounted an astounding campaign and shut them down (arguably the birthplace of the anti-nuclear movement). Unfortunately, Diablo Canyon nuclear power plant was a product of NIMBY.
Cleita
(75,480 posts)problems.
Brother Buzz
(36,214 posts)to the recipients that they were downwind of Bodega; the NIMBY perimeter grew exponentially.
blkmusclmachine
(16,149 posts)Cleita
(75,480 posts)look the other way. I just heard the siren they are testing just in case. What other industry has warning sirens like we are at war and about to be bombed? What other industry gives you free iodine pills just in case you got radiation?
Sirveri
(4,517 posts)We have an air raid siren that they test for the first Wednesday of the month. They used to sound it every time there was a shift change at the sugar factory, but they stopped doing that about 7 years ago. Air raid sirens are actually pretty common.
Cleita
(75,480 posts)It was done because many of the workers didn't have any way to tell time and after awhile for tradition until the residents complained which is why you haven't heard them in seven years.
This is quite different than those sirens. These sirens warn of impending explosion, from air raids, in mining towns for detonations gone wrong and now nuclear malfunctions.
Sirveri
(4,517 posts)You can still hear it once a month when they test it.
cascadiance
(19,537 posts)... up here in the northwest which is due for a big one.
Fortunately this conspiracy theorist site's prediction were wrong about what they predicted would happen Sunday in Seattle.
http://beforeitsnews.com/alternative/2014/10/live-earthquake-attack-during-seahawks-game-on-october-12-2014-3043650.html
That being said though there have been some more smaller quake activities up here in the Portland and Seattle area lately.
Brother Buzz
(36,214 posts)One would assume you could expect some creep or slippage on any of the active faults in you area.
Auggie
(31,061 posts)I hate cleaning-up broken glass and china more than I hate losing it -- not fun at 4:00 in the morning with no electricity and a freaked-out cat running around.
Mz Pip
(27,404 posts)Like this since I moved to CA in 1969. I can only hope I'll just be hearing the warning for the next 40 years.
We have a neighborhood preparedness group and do the best we can, I think. Short of moving to another region there's not much else to do. It's a ticking time bomb that will go off at some point but until there can be some accurate prediction we just carry on.
Auggie
(31,061 posts)imagining a 6.1, which is 40% more powerful than Napa's 6.0, is terrifying. The big one -- 6.9+ under, say, Oakland -- is going to level whole neighborhoods. That would be 22 times more powerful than what I just experienced.
http://www.bostonglobe.com/news/science/2014/08/25/how-much-quake-does-earthquake-quake/wdasqNjI68C1g7OBpGzvWJ/story.html