In early 2007, hidden beneath the waters of the Atlantic Ocean, an imperceptible yet significant event took place, prompting scientists to reassess their understanding of terrestrial processes. Orbital satellites detected a subtle fluctuation in gravitational pull, which stemmed from large-scale reorganization deep within the Earth.
According to the scientific publication Planet Today, this anomaly was observed in the eastern Atlantic sector between 2006 and 2008, peaking in January 2007. The signal spanned a vast area—approximately 4,350 miles. A research team led by Charlotte Gonier Gouranton from Université Paris Cité analyzed data from the GRACE satellite mission and uncovered a compelling pattern: a region exhibiting increased attraction adjacent to an area of diminished gravity.
Initially, researchers attempted to attribute this phenomenon to superficial causes, such as ocean water movement or sea-level variations. Nonetheless, computational modeling and evaluation of hydrological metrics failed to substantiate this initial theory. The team then shifted their focus to activities occurring much deeper underground, specifically at the mantle-core boundary.
One plausible explanation for this anomaly involves the phase transition of the mineral bridgmanite, which constitutes a major component of the lower mantle. Subjected to immense pressure and heat, the atoms of this substance can rearrange into a denser configuration known as post-perovskite. If an extensive region crosses the stability threshold, a substantial mass redistribution occurs without triggering seismic activity.
Intriguingly, around the same timeframe, a phenomenon dubbed the geomagnetic jerk—a sudden alteration in Earth’s magnetic field—was registered over the Atlantic. This correlation suggests a potential link between dynamics within the mantle and the planet’s liquid outer core, where the movement of molten iron generates the magnetic field.
The discovery made by the French scientists demonstrates the Earth’s capacity for swift, large-scale internal modifications that are detectable even from space. To gain a more precise comprehension of these mechanisms, ongoing monitoring and the integration of gravimetric data with seismic investigations will be necessary.
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