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Shifting core may have accelerated land movements

  1. May 22, 2004 #1

    Ivan Seeking

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  2. jcsd
  3. May 22, 2004 #2
    Good catch Ivan Seeking.

    There has been some controversy indeed about this phenomenon of the True Polar Wander.

    The main objective, magnetic orientation, is however a circular reasoning.

    Continental drift is derived from three dimensional magnetic orientation of rock core samples. This way the lattitude of the sample can be estimated, when it was formed with the prior assumption that the magnetic pole would also be the geographic pole.

    Now if somebody assumes that the whole mantle- lithosphere wandered around, the magnetic orientation is used to "refute" it. So how does that work: the refuter -uses the calculated latitude of the samples (unaware of how it was calculated) to show the position of the magnetic North Pole assuming that this would be identical to the Geographic North pole. And of course things add up exactly.
    So as a result he sees not a trace of a True Polar Wander. No wonder, since it's circular reason. A used to get B. B used to get A.

    BTW The current magnetic Soutph Pole is not even within the southern (ant)Arctic circle.
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