Everything Everywhere Daily Earth’s Magnetic Pole Reversals (Encore)
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Mar 20, 2025 Discover the fascinating phenomenon of Earth's magnetic pole reversals, which occur every 450,000 years. Explore how scientists analyze magnetic minerals in rocks to uncover the history of these flips. Delve into the potential impacts on the biosphere and humanity, including links to extinction events like that of the Neanderthals. The uncertainty surrounding future reversals raises intriguing questions about what might happen if they occurred today. Buckle up for a journey through time and magnetic mystery!
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Magnetic Record in Rocks
- Magnetic minerals in rocks align with Earth's magnetic field as they cool, preserving past magnetic orientations.
- Symmetric magnetic stripes on the seafloor record the history of Earth's magnetic pole reversals.
Random Timing of Pole Reversals
- There have been 183 magnetic pole reversals in the last 83 million years, averaging one every 450,000 years.
- These reversals occur randomly rather than on a regular schedule.
Geomagnetic Excursions Explained
- Geomagnetic excursions are short-term, significant deviations in Earth's magnetic field lasting thousands of years.
- Since the last major reversal 780,000 years ago, there have been 12 such excursions.