Huge volcano erupts from underwater

Scientists have discovered the 820m-high volcano in the western Indian Ocean, off the coast of Madagascar, after a series of extremely puzzling earthquakes.

After collecting geological data, including information from a 2019 underwater survey of the area, the team of researchers realized that there was a new underground volcano 1.5 times as tall. World Trade Center tower in New York. Furthermore, this volcanic eruption was derived from the deepest magma reservoir known to scientists.

The skyscraper-tall volcano formed on the seabed in the western Indian Ocean, off the coast of Madagascar.

Lead researcher Nathalie Feuillet, a marine geoscientist at the Paris Institute of Globe Physics in France, said: 'The magma source, the reservoir is very deep, about 55 kilometers underground. This is the first time we've seen such a deep reservoir at the bottom of the lithosphere, Earth's outer crust."

From May 2018 to May 2021, more than 11,000 earthquakes were detected that shook Mayotte, a small French island located between Madagascar and Mozambique. The strongest quake has a magnitude of 5.9, but there are also strange tremors, or very low frequency earthquakes, that originate deep underground that we cannot feel.

This sudden seismic activity is surprising, since only two earthquakes have been detected near Mayotte before.

In July 2018, scientists realized that Mayotte was moving east about 20 centimeters per year.

In May 2019, Romuald Daniel, Feuillet and colleagues had the opportunity to take a trip aboard the research vessel Marion Dufresne. The team knew there had been a magma event east of Mayotte, but they weren't sure if the magma was deep under the crust or if it erupted into the seafloor.

Teams worked around the clock, divided into shifts to pinpoint the exact location, in less than two weeks, of nearly 800 of the largest earthquakes (magnitude 3.5 to 4.9).

"We found that the majority of these earthquakes were located fairly close to the island (10km off the island's east coast but very deep (20 to 50km) , " Feuillet wrote.

Then, the ship's multi-beam echometer, which emits sound waves to map the seafloor and water column, found something "very large" about 31 miles east of Mayotte.

It was an underwater volcano as tall as a building . This volcano is brand new; it was not there in 2014, according to an earlier survey by the French Naval Hydrographic and Oceanographic Agency.