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Big Sumatra Quake: Wave hits Sri Lanka, India,

  1. Dec 26, 2004 #1


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    this BBC article has a map

    people who regularly watch broadcast TV will have already seen this
    but those who dont (like myself) may not have

    many thousands of lives were lost in the Tsunami which spread out from the point in Indonesia where the quake occurred
    the quake was said to be the worst in 40 years
    (I havent had time to compare several sources for confirmation)
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  3. Dec 26, 2004 #2


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    here are some technical specs on the quake from the USGS


    the quake was 8.9

    I read somewhere that at the quake the seafloor (temporarily?) shifted up or down by several (I wont say how many) meters----this sounds like it needs confirmation, does anyone have something more exact about this
  4. Dec 26, 2004 #3
    I heard that whole earth has stopped moving or something like that ,Holy Cow! maybe that is it for us humans.Mother earth is trying to shake out this vermin/pest out of itself.
  5. Dec 26, 2004 #4


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    dont worry we can just put ashes on ourself and beat ourselves with
    a few tree branches and everything will be all right
    this has been tried in Europe some time ago and worked fine
    I saw it in the Ingmar Bergman movie called "Seventh Seal"
    Last edited: Dec 26, 2004
  6. Dec 26, 2004 #5


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    :cry: !

    Wonder how fast can those things travel ... isn't there like a possibility to give a warning or something after the quake is registered, the word tsunami alert rings some bells ? Was just wondering since it did happen quite far off from India and Sri Lanka, which appear to have suffered the most.
  7. Dec 26, 2004 #6

    There is a possibility that the earthquake of : http://sify.com/news/fullstory.php?id=13635761

    May have been a 'trigger' for the one in Indonesia.
  8. Dec 27, 2004 #7
    Considering the depth of the sea in the are, i'd say around 700/900 Km/h
    The deeper the sea, the higher the velocity.
    A tsunami only becomes destructive once the seafloor starts rising.
    Then the water column and velocity (due to friction with the rising seafloor) decrease.
    The energy "stored" in the 6Km column of water can't just disapear.
    In other words, it has to go somewhere, in case of a tsunami it means the watercolumn elevates abouve the normal sealevel.
    By how much is dependable on how steeply the seafloor rises and the original depth and velocity.

    In Sri Lanka the sea floor rises very steeply from around 5Km deep to the surface, in other words the actual wave hitting the beach is enormous.
    From the coastline land inwards, the land is rather flat, in some parts even diving below the normal sealevel.
    Because of this the wave can penetrate the land for a great distance before it has lost enough of it energy to no longer be destructive.
    I belive in Sri Lanka the wave penetrated the land for over a Km before finally loosing its power.

    After the wave has lost its power, the water will start running back to sea, the current will drag anything that is loose or not bolted (very securely) back into the sea.
    Ant human trapped in this current (and miracilously is still alive) will most likely be crushed to death by debry.

    In short, a Tsunami is a *****.

    About the warning part.
    In Thailand the communications are good enough to be able to warn a lot of ppl with an 45min warning.
    This is not the case for small islands and most of India/Shri Lanka, this is the reason most of those ppl didn't know what hit them.
    Ironically, a lot of ppl actually came to the shore to whatch a mysterious drop in sealevel, a prelude to a Tsunami.
    To bad they didn't know what the were looking at. :grumpy:
    Last edited: Dec 27, 2004
  9. Dec 27, 2004 #8
    Who knows.
    Could have been because of that quake, or just because this one was due.
    Good chance you'll never know.
  10. Dec 27, 2004 #9


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    Regarding earthquake-tsunami warning system around Indian Ocean

    Asia Considers Disaster-Warning System

    Last edited: Dec 27, 2004
  11. Dec 27, 2004 #10
    Sensitive Seismicity...

    Richter Scale:
    [tex]R = \log \frac{I_R}{I_0}[/tex]

    Richter-Orion Scale:
    [tex]10^R = \frac{I_R}{I_0}[/tex]
    [tex]I_0 = 2.390*10^{-7} \; Megatons \; (Mt)[/tex] - Richter-Orion zero-level Constant
    [tex]I_R = I_0 10^{R}[/tex] - Richter-Orion Scale Magnitude

    Magnitude 9.0 Richter-Orion Magnitude:
    [tex]I_{9.0} = I_0 10^{9.0} = 239.005 \; Megatons \; (Mt)[/tex]

    [tex]\boxed{I_{9.0} = 239.005 \; Megatons \; (Mt)}[/tex]

    The Richter Scale is a measurement of a seismic magnitude, however, the Richter-Orion Scale is a measurement of a seismic events...destructibility.

    Based upon the Richter-Orion equation, what is the R (Richter) value for 1 kiloton?

    Based upon the Richter-Orion equation, what is the R (Richter) value for 1 Megaton?

    Based upon the Richter-Orion equation, what is the R (Richter) value for 10 Mega Megatons?

    Seismograph record:


    Attached Files:

    Last edited: Dec 28, 2004
  12. Dec 28, 2004 #11
    I guess most people don't realize the scale of this incident, so far there are 40 thousand death found officialy, but there are a lot more people missing, unofficialy the number already crosses the boundary of 100 thousand death, we are talking of more than the double of death of hiroshima/nagasaky bombs, this is one of the biggest incidents in history
  13. Dec 28, 2004 #12


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    More on warning systems: there are several in the pacific and they work rather well: http://wcatwc.gov/

    Unfortunately, these countries are not developed enough to have them - and even though the site I linked above put out a warning, these countries don't have the necessary infrastructure to promulgate it. It really is sad - with 1-3 hours notice, there is no reason why those beaches shouldn't have been utterly deserted.
  14. Dec 28, 2004 #13
    How did sea mammals and other critters reacted to early signs of incoming wave?
  15. Dec 28, 2004 #14
    With all of the deaths on the micro islands that apparently suffered complete genocide and have not officially been counted yet, plus all of the malaria, cholera, exposure and starvation that with claim more lives in the next month, it seems to me that the death toll will top one million by February 2005.

    • And, Patrick Nicholson of the Catholic Agency for Overseas Development suspects the worst for inhabitants of islands off the tip of Sumatra, close to the epicenter of Sunday's powerful quake.

      "Government reports say the population there, 76,000 ... planes, spotter planes went to the area and they saw no people whatsoever on the islands, badly destroyed," he said.
  16. Dec 28, 2004 #15
    You know, a nuke placed in the right location on a fault line could be the primer for such an event!!
  17. Dec 28, 2004 #16
    There are few US and Russian nuclear subs with nukes lying and rusting on the seafloor, who knows maybe one just blew up.
  18. Dec 29, 2004 #17


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    We do know the quake was not caused by that. Explosions have a distinct seismic signature.
  19. Dec 29, 2004 #18


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    The USGS website puts the event at about 30 km (18.6 miles) "set by location program", which apparently is close to the default value for earthquakes under the ocean floor - so this is not a thermonuclear warhead detonating on the seafloor, which would have been more radially symmetric anyway. The tsunamis went predominantly E-W.

    The earthquake was much bigger than the major nuclear warheads.
  20. Dec 29, 2004 #19


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    Wiki has a nice page on this.

    Last edited: Dec 29, 2004
  21. Dec 29, 2004 #20
    Geophysics Geovortexes...

    Based upon these photos, I notice that tsunamis also appear to produce large scale whirlpools and vortexes and gigantic swirl pattern waves, from both the negative and positive tsunami amplitudes, which would seem to require further catagorization.

    The determination of anything caught in such massive vortexes, is probably fateful.

    The most powerful Earthquake on record was 9.5:
    [tex]I_{9.5} = 755.784 \; Megatons \; (Mt)[/tex]

    The 11 largest global magnitude seismic pattern occurs in the Pacific Ocean along the 'ring of fire' crustal fracture:

    Accordign to the statistical Law of Averages for the 11 largest recorded global magnitude seismic events, to record such events occur with a frequency of 8.9 years and have an average magnitude of 8.855.
    [tex]I_{8.855} = 171.158 \; Megatons \; (Mt) \; every \; 8.9 \; years[/tex]

    Based on the statistical Law of Averages for the 11 largest recorded global magnitude seismic events, the next expected large magnitude quake is expected to occur around 2013 with a magnitude around 8.9 around the Pacific 'ring of fire'.

    Excellent satellite photos of the tsunami event!:


    Attached Files:

    Last edited: Dec 30, 2004
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