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Could the moon be considered as a threshold triger factor for eathquakes

  1. Sep 10, 2008 #1
    An article in the National Geographic states: "According to Berkland, the U.S. Geological Survey said such a theory is ridiculous—the Earth is 82 times more massive than the moon. Though the Earth can trigger quakes on the moon, they said, the moon is too small to trigger any earthquakes."

    But is it not reasonable to consider the posibility that the moons gravity could play a part in the release of stored energy in the earths crust, kind of like the straw that breaks the camels back. Thresholds are by their nature unstable and just like the tipping point of a spring loaded light switch, they require very little effort to finally make them click.

    The moon regulates a lot of aspects of the earths behavior, might it not also be responsible for minimising in however small an amount, the severity of earthquakes by providing a slight nudge to bring them out sooner?

    Last edited by a moderator: Apr 23, 2017
  2. jcsd
  3. Sep 21, 2008 #2
    John Richard asked about the moon’s role in earthquakes on September 10. I note no replies and have formed a brief one. I looked first at the internet, typing earthquake moon on google. A site with allegations and information in addition to the one attached to the query was found. http://en.wikipedia.org/wiki/User:Wikinaut/Moon-Earthquake-Theory
    Here a linkage to new and full moons was asserted without much data. Another site was loaded with information http://earthquake.usgs.gov/eqcenter/ [Broken] , pointing out that moonquakes are influenced by the Earth, an encouraging statement that was not documentyrd. http://earthquake.usgs.gov/learning/facts.php [Broken]

    The need is to assess the Moon’s position in relation to the earthquake at earthquake onset. Longitudinal angle, the difference in longitude between the earthquake site and the Moon at the time of the quake, including sign, may be used as a first approximation. Recent earthquakes are shown on the usgs site and the Navy has a site for moon longitude that appears potentially useful. A German site http://www.jgiesen.de/moonmotion/index.html and some astrology sites are alternatives. I would recommend that you select 30 usgs earthquakes by minimum magnitude around the World, attach their longitudinal angles (+180 to -180 degrees), and then simply plot them. If a relation is apparent you might post the graph and we can go on. If you are not sure, add another 20 or 30, then give up. There are simple statistical tests that can be used to formalize the analysis. But usually your eyes can tell you. There is a precedent for looking http://www.newton.dep.anl.gov/askasci/gen99/gen99048.htm says that more earthquakes in California are in the morning than the evening, but the numbers are not very large. A relation that doesn’t show up easily can create more problems than it can solve. The Sun may be brought in by adding time of day, but latitude and Earth tilt will pull you quickly into trigonometry and you should resist until you have early success.

    Good luck, you may be surprised by the outcome, but please share it in any case.
    Last edited by a moderator: May 3, 2017
  4. Sep 22, 2008 #3
    Thank you for your encouragement DEMcMillan, I will undertake the preliminary assesment using your very useful tips and links and report back in due course.

    Thank you again

    John Richard
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