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An Early Warning System For Earthquakes

Posted by kdawson on from the whole-lotta-shakin' dept.

Iphtashu Fitz writes "Would 15 seconds be enough warning time to prepare for an earthquake? It certainly wouldn't be long enough to evacuate from where you live, but it may be just long enough to get out of a building or brace yourself in a doorframe or under a solid desk. Italian scientists may have discovered a way to measure the initial shockwave of an earthquake two seconds after it starts, and from it predict the extent of the destructive secondary wave that will follow. It typically takes twenty seconds for the secondary wave to spread 40 miles, so sensors that can transmit warnings at the speed of light may provide just enough warning before a major quake for people to brace themselves. Even more importantly, such a warning could allow for utilities like gas companies to close safety valves, preventing potential fires or explosions in the aftermath of the quake."

5 of 147 comments (clear)

  1. One powerful earthquake? by solafide · · Score: 4, Interesting
    It takes 20 seconds for it to travel 40 miles? How much power has that secondary wave lost in those 40 miles? Wouldn't it take one really powerful earthquake for you to need to take cover 40 miles from the epicenter?

    (I'm not an expert on earthquakes, but 40 miles seems like a long way for the earthquake to travel.)

    1. Re:One powerful earthquake? by Beryllium+Sphere(tm) · · Score: 5, Interesting

      1985, Mexico City, buildings collapsed when the center of the earthquake was 400 km away. That one was unusual but it shows what's possible.

      The other thing you can do with 10-20 seconds of warning is apply emergency brakes on the bullet trains, which I believe Japan has arranged to do.

    2. Re:One powerful earthquake? by davidsyes · · Score: 3, Interesting

      I was lucky that day. I had only minutes before left Grand View (Chinese) Restaurant (they changed names to Fortune after the quake) with a few cartons of food and couldn't decide whether to go straight back to Milpitas or to dart over to Embarcadero and shoot a few pictures.

      By the time I'd decided it wouldn't be good to get the food late to some people I told about the restaurant, when I decided to head on south, I was barely out of Oakland, somewhere south of Cypress on 880 because. Had I gone to SF, I'd have been SOMEwhere on the Cypress. It's possible I could have also been somewhere before the fallen deck section, but that all could have depended on how many people on the Cypress would have been in my way (back then I might have wanted to speed, might have just relaxed and slipped in and cranked up my Depeche Mode cassettes, (but instead I kept the KGO talk on), blah blah blah...) and I am SURE I'd have probably died that day had I not just taken the food straight to my friend.

      I think I was barely north of the Marina shopping outlet when my steering started acting up. I couldn't believe my barely 1 year old car was acting up. Then the radio went out. There wasn't too much traffic in that section, so my eyes fixated partly on the road and partly on the trees. When I saw them swaying, I knew my car was OK, but the radio was hissing. Only a few weeks earlier IIRC, KGO's antenna near the Dumbarton Bridge went out and needed repairs, so I thought they were having problems. I tuned to other stations only to hear noise and mostly silence, but sporadic bits mentioned major earthquake.

      Fortunately, the roads don't open up like they do in hollywierd flicks. Fortunately it wasn't in the thick of commuter traffic, or there might have been collisions all up and down the freeway for dozens of miles if anyone freaked and lost control of the car. I was fortunate that day...

      --
      Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
  2. Safety valves? by EaglemanBSA · · Score: 4, Interesting

    There would still be gas in the main lines, how would shutting a safety valve keep a broken pipe from leaking gas already in it?

    --
    Quiz: True or False -- On a scale of 1 to 10, what is your middle name?
  3. Doesn't japan have something like this? by Hays · · Score: 3, Interesting

    I thought the high speed trains in Japan would stop in the event of an earthquake (before the earthquake actually hit them), http://en.wikipedia.org/wiki/Shinkansen

    "In the event of an earthquake, an earthquake detection system can bring the train to a stop very quickly"

    Anyway, the idea of a broadcast system to warn of an earthquake is pretty obvious, the engineering task of doing it right without false positives is pretty difficult I bet.