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Induced seismicity and low frequencies

  1. Jan 21, 2010 #1
    Maybe a dumb question, and i've been wondering this a long time, but the Haiti thing reminded me...
    Is it possible for electronically produced frequencies to cause seismic activity? I know that injection wells/fracturing/oil & gas wells/dams can cause induced seismicity, but is there anyway at all for any type of ULF/ELF/LF/HF waves to cause pent up energy at tectonic edges to be released?
    Thanks.
     
  2. jcsd
  3. Jan 21, 2010 #2
    If you could get an electronic signal to cause an explosion or an implosion then yes it is possible. That said, the electronic signal could only be used to trigger such a thing, it is not enough that an electronic signal could in and of iteself be that explosion/implosion that induces seismicity. In nature, I am not aware of any source mechanism that would be triggered by electromagnetic wave (perhaps I'm overlooking something?). A remotely detonated mine would be an example of a man made source that would, in a round-about kind of way, be triggered electromagnetically. However this is not a very satisfying link. For ultimately the sesimic wavelet would carry no trace of the elctromagnetic signal, and the seismic wavelet is a causal thing, so physically we can safely say that the electromagnetic pulse did not cause the seismicity, it simply triggered another device which caused the pulse. So in brief I'd say no, remote detonation is probably as close as you're gonna get.
     
  4. Jan 22, 2010 #3
    What about a resonance factor? Can electronic frequencies of any kind cause physical vibrations that could in turn cause a substrate like talc, or sand, to pack-down, or behave differently, property wise?
     
  5. Jan 25, 2010 #4
    Cymatics
     
  6. Jan 25, 2010 #5
    Exactly.......but can these types of vibrations be caused by electronic means?
     
  7. Jan 26, 2010 #6
    Electromagnetic earthquake precursors have been observed and are an intriguing area of study in earthquake prediction.

    e.g.
    http://walrus.wr.usgs.gov/infobank/programs/html/school/moviepage/08.02.18.html

    However, a note of caution, I know of no natural mechanism that would trigger seismicity by electromagnetism, and remember, strange animal behaviour has also been observed before earthquakes and yet nobody seriously considers that strange animal behaviour triggers earthquakes!
     
  8. Jan 26, 2010 #7
    Yes, but weren't these EM signals naturally produced? They were the precursors of earthquake activity, but not the causes....correct?
    I know it's still a mysterious phenomenon how these EM fields seem to spike before seismic activity, but are these EM fields the cause? And if so, could these types and strengths of EM signals be reproduced by man, electronically?
     
  9. Feb 9, 2010 #8
    I'm wondering if the same effect produced with Tesla egg of Columbus can be done with Earth crust by inducting current with EM field and doing it such as to produce resonance.
     
  10. Feb 13, 2010 #9
    It seems the current research points toward a hypothesis where the electromagnetic radiation is caused by the earthquake rather than the trigger for the earthquake.

    Perhaps the animals can sense the electromagnetic changes which is why their behavior changes before a large earthquake.

    Comment:
    That does not mean a large electromagnetic trigger could not also trigger an earthquake, however, as Billiards noted there would need to be a mechanism to create the electromagnetic disturbance to trigger the earthquake.



    http://www.sciencedirect.com/scienc...serid=10&md5=4db5ce04c241b9c2d45c16e739a0173d


    http://jjap.ipap.jp/link?JJAP/37/5016/ [Broken]
     
    Last edited by a moderator: May 4, 2017
  11. Feb 14, 2010 #10
    Interesting research Saul. I had not previously really appreciated this phenomenon, I think this field of research is most active in the Far East. I'm guessing "Benioff electromagnetic radiation" (the term used in the first reference) is the technical term for "earthquake lightning" (the term used in the second reference)?

    If they are the same thing then it seems we have two proposed mechanisms for generating the electromagnetic radiation: (1) due to electric discharge by dielectric breakdown of ambient gases from friction contacts between rock minerals, and (2) Change in seismic stress releases piezo-compensating, bound charges due to changes in the piezoelectric polarization of quartz grains in granitic rocks. I would expect that both mechanisms are at play but it would be interesting to know which is the dominant -- clearly this would be dependent on geology as you would need the right mix of gases for the first, and sufficient quantities of quartz for the second. Of course, there is probably a third mechanism that has been overlooked here.

    Note that in both these papers the electromagnetic radiation is in response to changes in the stress. Those changes in stress are also the cause of the earthquake (the rocks want to be in equilibrium just like pretty much everything else in physics, if you put a load on them that they are not strong enough to support then they will adjust to find a more stable equilibrium, when that happens suddenly and releases a lot of energy then we call that an earthquake). So, to be clear, this research does not propose a mechanism for triggering earthquakes electromagnetically. Rather, these papers propose physical mechanisms for explaining the cause of electromagnetic radiation which we observe to precede earthquakes. (I'm not 100% certain on the strength of the link between electromagnetic anomalies and earthquakes however, we must be careful that these observations are not coincidental magnetic storms which are pretty common -- is there something characteristic about this electromagnetic energy? Has it been observed frequently enough to confirm the link on statistical grounds?) I agree with Saul that it is at least plausible, if not likely, that animals respond strangely to this electromagnetic radiation -- if there is some data which shows the relative timing of the events this hypothesis would be easily falsified if animals were seen to react strangely before the onset of anomalous electromagnetic activity. However, again, I would question why animals aren't observed to behave strangely during magnetic storms -- which makes me wonder if there is a characteristic frequency of the earthquake precursor electromagetic energy.
     
  12. Feb 22, 2010 #11
    The only thing that can induce an earthquake is something that can effect the differential stress or the strength of rocks (coefficient of friction). That said, unless you juxtaposed two lithologies of wildly different electromagnetic properties, i can't imagine how EM energy could trigger seismicity. It's gotta from loading, pore fluid pressure, or changes in temperature adequate enough to effect the rheology.
     
  13. May 18, 2011 #12

    Dotini

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    http://arxiv.org/abs/1105.2841
    The recent M9 Tohoku Japan earthquake of March 11, 2011 was the largest recorded earthquake ever to hit this nation. We retrospectively analyzed the temporal and spatial variations of four different physical parameters - outgoing long wave radiation (OLR), GPS/TEC, Low-Earth orbit tomography and critical frequency foF2. These changes characterize the state of the atmosphere and ionosphere several days before the onset of this earthquake. Our first results show that on March 8th a rapid increase of emitted infrared radiation was observed from the satellite data and an anomaly developed near the epicenter. The GPS/TEC data indicate an increase and variation in electron density reaching a maximum value on March 8. Starting on this day in the lower ionospheric there was also confirmed an abnormal TEC variation over the epicenter. From March 3-11 a large increase in electron concentration was recorded at all four Japanese ground based ionosondes, which return to normal after the main earthquake. We found a positive correlation between the atmospheric and ionospheric anomalies and the Tohoku earthquake. This study may lead to a better understanding of the response of the atmosphere /ionosphere to the Great Tohoku earthquake

    Respectfully submitted,
    Steve
     
  14. May 19, 2011 #13

    Dotini

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    http://www.msnbc.msn.com/id/43083235/ns/technology_and_science-science/
    An MSM take on the correlation of atmospheric/ionospheric anomalies prior to earthquakes, largely based on the paper cited just above.

    To revisit the OP: "Is it possible for electronically produced frequencies to cause seismic activity...is there anyway at all for any type of ULF/ELF/LF/HF waves to cause pent up energy at tectonic edges to be released?"

    The question is so far unanswered. But in view of the potentially disastrous consequences of major earthquakes, it seems important to study, especially for the value of improved ability to predict.

    Respectfully,
    Steve
     
    Last edited: May 19, 2011
  15. May 19, 2011 #14

    Dotini

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    http://www.technologyreview.com/blog/arxiv/26773/?p1=Blogs
    "These kinds of observations are consistent with an idea called the Lithosphere-Atmosphere-Ionosphere Coupling mechanism. The thinking is that in the days before an earthquake, the great stresses in a fault as it is about to give cause the releases large amounts of radon.

    The radioactivity from this gas ionises the air on a large scale and this has a number of knock on effects. Since water molecules are attracted to ions in the air, ionisation triggers the large scale condensation of water.

    But the process of condensation also releases heat and it is this that causes infrared emissions. "Our first results show that on March 8th a rapid increase of emitted infrared radiation was observed from the satellite data," say Ouzounov and co.

    These emissions go on to effect the ionosphere and its total electron content."


    So there is a strong coupling of the lithosphere-atmosphere-ionosphere on March 8th. Could a geologist comment upon this please, because I do not understand how the radon gases could be released prior to earth movement. Wouldn't it be expected that such gases would be released mainly after the quake on March 11th?

    Thank you and respectfully submitted,
    Steve
     
    Last edited: May 19, 2011
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