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There are many factors that drive the movement of tectonic plates on the surface of asthenosphere, and some of these factors have a larger contribution than others (e.g. slab suction).

One driving factor of less significance influencing tectonic plate movement is however the Earth's rotation. Apparently one such effect of the Earth's rotation is the "Pole flight force" which results in an equatorial drift of the plates to the equator.

Why does the rotation of Earth result in tectonic plates having a tendency to want to move closer to the equator?

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  • $\begingroup$ Is this just to do with continental plates? If so, first guess would be something to do with the fact that continental plates are lighter than basalt ocean plates, plus centripetal force. $\endgroup$ – naught101 Apr 20 '14 at 4:13
  • $\begingroup$ On wikipedia tectonics page it says under the heading of rotational drivers for tectonics: "Pole flight force: equatorial drift due to rotation and centrifugal effects: tendency of the plates to move from the poles to the equator ("Polflucht");" if that's of any help $\endgroup$ – Kenshin Apr 20 '14 at 8:18
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I'm not a tectonicist or a science historian, but as far as I know the ‘pole flight force’ or Polfluchtkraft was introduced by Wegener in his theory of continental drift. Essentially it's just the application of centrifugal force to continents (or, if we are now considering it within the plate tectonic paradigm, to plates). As stated in the Wikipedia article you link to, this force is far too weak to account for plate motions, and this very fact was one of the reasons for the scientific community's rejection of continental drift. Modern tectonics doesn't seem to consider it even as a measurable contributing factor. The only modern references I've found to it have been in historical contexts, such as in Krause (2007). The subtitle of this paper, ‘Vergessene Begriffe der Geologiegeschichte’, translates to ‘forgotten concepts of geological history’, and as far as I can tell this is an accurate summary of Polflucht's current status.

  • Krause, R.A., 2007. Die Polfluchtkraft: Der LELY-Versuch – Vergessene Begriffe der Geologiegeschichte. Polarforschung 76 (3), 133–140. DOI: 10013/epic.29962
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  • $\begingroup$ thanks I'm going to accept this as an answer because I myself have done alot of reading since asking this question and I believe you are correct. $\endgroup$ – Kenshin Apr 23 '14 at 12:58
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    $\begingroup$ my suspicion is that it also has to do with Euler pole models, which would intrinsically shift it towards the equator as you have the mechanism governing tectonic movement modeled as a great circle shifting on a sphere. $\endgroup$ – Neo Apr 23 '14 at 16:04

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