One idea is that the mountains are part of the lower mantle It was hot Due to its proximity to Earth’s luminous core. While the mantle can reach up to 3,700°C (6,692°F), it is relatively light – the core can reach an atomic bending height of 5,500°C (9,932°F) – not far from the hotter surface of the sun. That hottest part From the core-mantle boundary, it is suggested, they may become partially molten — that’s what geologists see as the ULVZ.
Alternatively, Earth’s deepest mountains could be made of a material quite different from the surrounding mantle. Incredibly, it is believed that they may be remnants of ancient oceanic crust that, in their depths, eventually disappeared. sink over hundreds of millions of years to settle above the core.
In the past, geologists have looked to the second mystery for clues. Deep mountains tend to be found near other mysterious structures: massive bubbles, or large low shear velocity provinces (LLSVP). There are only two: an amorphous mass called “Tuzo” under Africa, and another known as “Jason” under the Pacific Ocean. They are believed to be very primitive, possibly billions of years old. Again, no one knows who they are, or how they got there. But their proximity to the mountains has led to the belief that they are related in some way.
One way to explain this relationship is that it actually begins with tectonic plates sliding down into the Earth’s mantle, and then sinks to the core-mantle boundary. It then slowly spreads out to form various structures, leaving behind a series of mountains and clumps. That is, both are made of ancient oceanic crust: a mixture of basalt and sedimentary rock from the ocean floor, even though it was altered by intense heat and pressure.
Hansen thinks that the presence of mountains deep beneath Antarctica could counteract this. “Most of our study area, the Southern Hemisphere, is very far from those larger structures.”
To set up the Antarctic seismological station, Hansen and his team flew to suitable locations in helicopters and small planes, placing the equipment waist-deep in snow—some near the coast, under the gaze of the penguins, others inland.
It only takes a few days to get the first results. Instruments can detect earthquakes almost anywhere on the planet—“if they are big enough, we can see them,” says Hansen—and there are lots of opportunities. Records of the US National Earthquake Information Center About 55 worldwide every day.
While mountains deep within the Earth have been identified before, no one has verified them under Antarctica. It’s not near any of the blur points, or anywhere near where any tectonic plates have recently crashed. However, the team was surprised to find them at every site they sampled.
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Previously it was believed that the mountains scattered near the places occupied by the points. But Hansen’s results suggest that it may form a continuous mantle that envelops the Earth’s core.
Testing this idea will require further investigation: prior to the study of Antarctica, only 20% of the core-mantle boundary had been examined. “But we hope to fill this gap,” said Hansen, explaining that it also relies on developing new techniques to identify smaller structures. In some areas, the structure of the ULVZ resembles a plateau more than a mountain, so the entire layer is not yet visible – not visible on seismometers, if at all.
However, if a mountain is truly widespread, it will have implications for its components and how they relate to the large point structure. Could the smaller mountain-sized remnants of tectonic plates really end up that far from the big blobs?
Oddly enough, whatever we find, Antarctica’s strange frozen landscape has already given us clues about strangely hot mountains deep within the Earth.
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