Just before we entered the new millennium in 2000, a flurry of books touted the apocalyptic prediction of a “pole shift,” where Earth’s magnetic pole would move from north to south with untold catastrophic damage. Originally discredited by most people as an outlandish scare tactic devised to sell books, the concept of shifting magnetic poles seems now to have much more scientific credence ~ though the pace is different and the effects not necessarily so dire.
Not only do pole shifts actually occur, but they happen rapidly in a geomagnetic sense, as new geological findings near Battle Mountain, Nevada, show. The new discovery reinforces similar findings in 1995 at the Steens Mountains in southeastern Oregon.
Describing the new Nevada find, Science News states:
Magnetic minerals in 15-million-year-old rocks appear to preserve a moment when the magnetic north pole was rapidly on its way to becoming the south pole, and vice versa. Such ‘geomagnetic field reversals’ occur every couple hundred thousand years, normally taking about 4,000 years to make the change. The Nevada rocks suggest that this particular switch happened at a remarkably fast clip.
The Nevada find indicates the magnetic pole shift occurs at about one degree a week, while the Oregon evidence indicates up to six degrees a day.
Researchers aren’t sure why the geomagnetic field reverses itself. Many think it must have something to do with what creates the field in the first place ~ convective motions of liquid iron in the planet’s spinning outer core.
The last stable reversal occurred 780,000 years ago, according to Science News. Some geologists argue Earth is overdue for a reversal and might even be entering one now, as the geomagnetic field has been getting weaker over the past 150 years or more.
Click here for the complete Science News article.
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