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Tremors Predict California Earthquakes

johkir writes "A seismologist at the University of California Berkeley Seismological Laboratory has discovered mysterious tremors deep under the San Andreas Fault that may help predict future earthquakes. The episodes of tremors, which he calls chatter, last from four to twenty minutes and are being recorded from as deep as 40 kilometers beneath the surface -- up to four times the depth of normal earthquakes! These tremors also seem to occur a few weeks prior to detectable surface tremors. Article is published in Science Magazine, but you'll need a subscription, and it is covered in the San Francisco Chronicle and a UC Berkeley press release."

24 comments

  1. First impression. by Anonymous Coward · · Score: 0

    This seems quite Burtonesque.

  2. UC Davis by eikonoklastes · · Score: 5, Interesting

    Researchers at UC Davis have also recently made headlines trying to forecast earthquakes (Press release). I wonder if we're on the brink of a new understanding of earth's geophysical processes.

  3. We have a savior!!! by Anonymous Coward · · Score: 0, Funny

    Quick, let's put Michael J. Fox in charge of earthquake prediction!

    1. Re:We have a savior!!! by NonSequor · · Score: 1

      He can consult with the Pope too.

      --
      My only political goal is to see to it that no political party achieves its goals.
  4. Fingernails on Chalkboard? by TFGeditor · · Score: 0

    Lessee, tectonic plates sliding over one another in a subduction zone... ...yeah, that would make a noise, I think.

    --
    Ignorance is curable, stupid is forever.
  5. Look at these guys by Anonymous Coward · · Score: 0

    What a bunch of nerds!

    Do you really trust these dorks to predict your earthquakes? C'mon, you got to put some polish on this research if you want it to sell, baby!

  6. no evidence of volcanism huh? by fearanddread · · Score: 1
    "We see this kind of tremor activity inside volcanoes like Mount St. Helens," Nadeau said, "but that's due to the movement of rising magma, and in the tremors we've recorded there's no evidence of volcanism and no seismic waves typical of ordinary earthquakes."

    http://imdb.com/title/tt0120461/

  7. tremors? by flok · · Score: 1
    --

    www.vanheusden.com - home of Multitail, HTTPing, CoffeeSaint, EntropyBroker, rsstail, bsod, listener, nagcon, nagi
  8. When does California... by OAB_X · · Score: 1, Funny

    Not have earthquake warnings? If you build your state on a major fault line, you deserve what you get. Sure its all warm and everything, but you can get that in Florida, only thet have hurricanes instead.

    Moral of the story: Move from California to Toronto, no hurricanes/tornados/earthquakes. Just remember to buy a jacket before you leave home.

    1. Re:When does California... by TFGeditor · · Score: 1

      Why is parent modded down?

      It's a joke, I say, it's a joke, son!

      --
      Ignorance is curable, stupid is forever.
    2. Re:When does California... by superpulpsicle · · Score: 1

      Don't worry, California's one of those states where more people move out than move in every year. Eventually no one can afford to live in a state filled with overpriced real estate on top of a gigantic crack.

    3. Re:When does California... by Anonymous Coward · · Score: 0

      So you're trading off an earthquake for a cold, ugly, overpriced city, filled with unhappy, grumpy, materialistic people. I'd rather take my chances in an earthquake. All kidding aside, you would have been better off going to Vancouver.

  9. Another false discovery, USA stealing credit again by GISGEOLOGYGEEK · · Score: 3, Interesting

    This type of deep unusual tremor has been known of for several years.

    Roughly every 14 months, such tremors occur deep under Vancouver Island. Over a 2 week period, the tremors shift southward towards washington state.

    The tremors are related to the subduction of the pacific ocean under north america.

    The san andreas fault is a remnant of the subduction zone, where the pacific spreading ridge has already been consumed. This ridge is still a couple hundred km offshore of vancouver island.

    The deep tremors on the san andreas are probably caused by the change in strain on the system after the same tremors have occured up here. Yes, the deep tremor cycle did occur like clockwork, as predicted by the canadian pacific geoscience center a few months ago under vancouver island. Several 14 month cycles have been observed.

    The weird thing about the tremors is that it represents a rebound in the subduction of the ocean plate. instead of subducting a few cm per year, in two weeks the subduction reverses by about 5cm, and then goes back to the normal.

    It is thought that the changes in strain caused by all this may increase the short term chances of the next big quake hitting southwest BC by a large factor.

    Anywho, go away, there's nothing truly new to see here, it may not have been observed so far south before, but it is not a discovery of a new type of geologic activity, the Canadians already documented it, which maybe the media would have realized had they bothered to look outside your borders for something other than the injustices of Iraq.

    --
    George Bush + Linux = "I will not let information get in the way of the fight against Windows"
  10. We now have proof. by Eevee · · Score: 1

    Canadians don't read the articles either.

    It states quite clearly in the Berkley press release:

    ...are similar to those discovered in the past two years at subduction zones in Japan and the Pacific Northwest.
    Now why, you might ask, are they making a big deal out of this? It's because it's not happening on a subduction zone, but instead under a transform fault.
    1. Re:We now have proof. by GISGEOLOGYGEEK · · Score: 1

      how about you read closer yourself.

      The san andreas is a remnant of the subduction of the pacific spreading ridge.

      It didn't occur to you that there could still be a piece of the ocean plate descending at depth did it huh?

      --
      George Bush + Linux = "I will not let information get in the way of the fight against Windows"
  11. Re:Another false discovery, USA stealing credit ag by OccidentalSlashy · · Score: 0
    The deep tremors on the san andreas are probably caused by the change in strain on the system after the same tremors have occured up here.

    Actually, it was from millions of GFA gamers shooting up their prostitutes post coitus!

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    vicious, untreated political sewage...niche entertainment for the spiritually unattractive...worshipless pap
  12. Re:Another false discovery, USA stealing credit ag by OccidentalSlashy · · Score: 0
    which maybe the media would have realized had they bothered to look outside your borders for something other than the injustices of Iraq

    Are you kidding me?!?! I WISH they would frikkin cover that...Rummy says they haven't been armoring our hummers because of physics...and the media doesn't care! They don't care about the war at ALL except to print some one-dimensional closeups of soldiers' faces.

    --
    vicious, untreated political sewage...niche entertainment for the spiritually unattractive...worshipless pap
  13. We now have further proof. by Eevee · · Score: 1

    that Canadians don't read articles even after being called on it.

    The san andreas is a remnant of the subduction of the pacific spreading ridge.

    Okay, let's go to Plate Tectonics and Volcanoes and the San Andreas Fault for a quick lesson on the differences between subduction zones and transform faults.

    It didn't occur to you that there could still be a piece of the ocean plate descending at depth did it huh?

    Actually, it did occur to me. However, the article states this isn't at a subduction zone (45 degree slope) but rather at a transform fault (nearly vertical slope) and that the mechanism currently believed to cause the tremors in the subduction zones--fluids from seawater saturating the rocks--isn't present at the location. From the San Francisco Chronicle article:

    In California, the most mystifying feature of the unexplained tremors is that they are occurring right on the deepest part of the San Andreas -- a fault that does not involve subduction or volcanic activity.

    Furthermore, it should be noted that the activity at the Cascadia Subduction Zone isn't between the Pacific plate and the North American plate--the two plates involved in the San Andreas fault system--but rather between the Juan de Fuca plate and North American plate. So we can't just trace down the North American plate, assuming everything will be the same along it.

  14. Eh? by dj245 · · Score: 1
    Tremors Predict California Earthquakes

    A bad Tv series on the Scifi channel somehow predicts a major geological event?

    --
    Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
  15. Re:Another false discovery, USA stealing credit ag by hicksw · · Score: 1

    Well, I know Canada is a BLUE state.

    Is it time to invade Canada again?

  16. Re:Another false discovery, USA stealing credit ag by Anonymous Coward · · Score: 0

    Hot damn let's invade again. We'll bomb them back to the stone age-- revenge for 1812. Look at all the reasons:

    - They are a left leaning state with the dangerous goal of providing universal health care
    - They have nuclear technology
    - They don't agree with US foreign policy
    - They have scads of oil-- maybe more than anyone

    Is it a coincidence that these tremors are being reported in Canada? After all wouldn't an earthquake generating device be the ultimate weapon of mass destruction? What do you think all that high grade B.C. pot funds?

    We should invade and install a regime more friendly to US business and government interests. We'll get cheaper oil, cheaper prescription drugs and better pot. And Shania Twain in return for torturing us with Celine Dion for all these years.

  17. Re:Another false discovery, USA stealing credit ag by I+Sil+Zah · · Score: 1

    While yes similar tremors were reported in Canada, to my knowledge this is the first time that we've ever seen them on the San Andreas.

    I grew up in the Bay Area and was there for the 89 quake. With the San Andreas, everytime scientists find something that correlates with detectable earthquakes, it doesn't pan out.

    So the fact that the tremors were reported in Canada AND now they are being seen in San Andreas AND correlating to detectable earthquakes is very promising.

    What most people, even people in the Bay Area (who really should pay more attention to the models) don't realize is that if a big earthquake hits, its the composition of the ground thats against us, especially in San Francisco.

    We could have a really high fatality rate from just the quake let alone the aftermath, which is where most of the deaths were in 1909. Not to mention the fact that after 1909 city leaders were in such a rush to make it look like nothing happened that they lowered the building code instead of improving it, so it took a while before buildings were designed to hold up to an earthquake.

    If you look at the journal that this was published in, it wasn't published by mass market media. It was published by the American Association for the Advancement of Science. It is unfair to say that the "media" should have looked outside of "our" country before documenting "something other than the injustices in Irag." Science is a peer reviewed journal which means that the actual scientists doing the research write an article about their research when its ready to be published and submit it to a journal. That journal then sends it to other knowledgable scientists in that field to review what the researchers wrote to make sure its valid and not off the deep end and they backed up their work. If everythings okay, it goes to press. So the "media" didn't write anything.

    I can't see the article yet because its only online and I don't have access until its been printed. However, when my chemistry research got published all the relevent previous research was cited so I would bet that any similar tremors would be reported unless the Canadian tremors are actually different from these.

    You are obviously an intelligent person, you know a lot about geological activity. I would suggest that you not be so quick to judge everyone based on the country at which they're from. If you had actually tried to look at the article, you would have seen that it was a scientific peer reviewed article in a respected journal.