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10-05-12, 01:50 PM
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Plate tectonics is one of the most successful theories in the history of science. Beyond its scientific successes, it's widely accepted by the public, since it explains a lot about the world that we see around us.

But like other successful theories, it has its share of awkward inconsistencies. A recent paper in the Journal of Geophysical Research attempted to tackle one of these inconsistencies‚??finding an absolute reference frame for the movement of the plates‚??but failed so badly that its authors advise other scientists not to even bother trying. But as part of their failure, they came up with a new measure of one of the more unexpected consequences of plate tectonics.

All of plate tectonics is driven by density differences in the material beneath our planet's solid surface. These drive the shifting plates, power hot-spot volcanoes, and recycle material to the planet's surface. They also make sure that the mass of the Earth is never evenly distributed. As that mass shifts internally, it actually causes the Earth's spin to wobble around a bit. As a result, even the Earth's axis of rotation doesn't provide an absolute reference frame. In the process of failing to find an absolute reference frame, though, the authors have provided a detailed map of how the Earth's true pole has wandered over millions of years.

Read 17 remaining paragraphs (http://arstechnica.com/science/2012/10/no-absolutes-how-shifting-plates-completely-remake-the-earth/) | Comments (http://arstechnica.com/science/2012/10/no-absolutes-how-shifting-plates-completely-remake-the-earth/?comments=1#comments-bar)



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