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The Real Signs of Time
Scientists find link between magnetic reversal and tectonic plate movements
“Dynamo faltering from rapid changes in
interior planetary temperatures is likely accelerating magnetic field
reversal and tectonic plate movements.” -The Extinction Protocol, page 475
October 30, 2011 – The
Earth’s magnetic field is produced by the flow of liquid iron within
its core, three thousand kilometers below our feet. What made
researchers think of a link between plate tectonics and the magnetic
field? The discovery that convective liquid iron flows play a role in
magnetic reversals: experiments and modeling work carried out over the
last five years have in fact shown that a reversal occurs when the
movements of molten metal are no longer symmetric with respect to the
equatorial plane. This “symmetry breaking” could take place
progressively, starting in an area located at the core-mantle boundary
(the mantle separates the Earth’s liquid core from its crust), before
spreading to the whole core (made of molten iron). Extending this
research, the authors of the article asked themselves whether some trace
of initial symmetry breakings behind the geomagnetic reversals that
have marked the Earth’s history, could be found in the only records of
large-scale geological shifts in our possession, in other words the
movements of continents (or plate tectonics). Some 200 million years
ago, Pangaea, the name given to the supercontinent that encompassed
almost all of the Earth’s land masses, began to break up into a
multitude of smaller pieces that have shaped the Earth as we know it
today. By assessing the surface area of continents situated in the
Northern hemisphere and those in the Southern hemisphere, the
researchers were able to calculate a degree of asymmetry (with respect
to the equator) in the distribution of the continents during that
period.
In conclusion,
the degree of asymmetry has varied at the same rhythm as the magnetic
reversal rate (number of reversals per million years). The two curves
have evolved in parallel to such an extent that they can almost be
superimposed. In other words, the further the centre of gravity of the
continents moved away from the equator, the faster the rate of reversals
(up to eight per million years for a maximum degree of asymmetry). What
does this suggest about the mechanism behind geomagnetic reversals? The
scientists envisage two scenarios. In the first, terrestrial plates
could be directly responsible for variations in the frequency of
reversals: after plunging into the Earth’s crust at subduction zones,
the plates could descend until they reach the core, where they could
modify the flow of iron. In the second, the movements of the plates may
only reflect the mixing of the material taking place in the mantle and
particularly at its base. In both cases, the movements of rocks outside
the core would cause flow asymmetry in the liquid core and determine
reversal frequency. -Physics
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