Scientists have discovered an 820-meter-high underwater volcano in the western Indian Ocean, off the coast of Madagascar, following a series of perplexing earthquakes.
After collecting geological data, including information from a 2019 underwater survey of the area, the research team realized that there is a new underwater volcano that is 1.5 times taller than the One World Trade Center in New York. Furthermore, this volcanic eruption originates from the deepest magma reservoir known to scientists.
An underwater volcano as tall as a skyscraper formed on the ocean floor in the western Indian Ocean, off the coast of Madagascar.
Lead researcher Nathalie Feuillet, a marine geologist at the Institute of Earth Physics in Paris, France, stated: “The magma source, the reservoir is very deep, about 55 kilometers underground. This is the first time we have seen such a deep reservoir at the base of the lithosphere, the outer shell of the Earth.”
From May 2018 to May 2021, over 11,000 earthquakes were detected that shook Mayotte, a small French island located between Madagascar and Mozambique. The strongest earthquake registered a magnitude of 5.9 on the Richter scale, but there were also strange seismic events or very low-frequency earthquakes originating deep underground that we could not perceive.
This sudden seismic activity was surprising, as only two earthquakes had been detected near Mayotte previously.
In July 2018, scientists realized that Mayotte was moving eastward at a rate of about 20 centimeters per year.
In May 2019, Romuald Daniel, Feuillet, and their colleagues had the opportunity to embark on a research voyage aboard the Marion Dufresne. The research team was aware of a magma event to the east of Mayotte, but they were unsure whether the magma was deep beneath the crust or had erupted onto the ocean floor.
The teams worked around the clock, divided into shifts to pinpoint the exact location, and within less than two weeks, nearly 800 of the largest earthquakes (with magnitudes between 3.5 and 4.9) were recorded.
“We found that most of these earthquakes were located quite close to the island (10 kilometers off the eastern coast of the island) but at great depths (between 20 and 50 kilometers)”, Feuillet wrote.
Subsequently, the ship’s multi-beam echo sounder, 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 entirely new; it was not present in 2014, according to previous surveys by the French Naval Hydrographic and Oceanographic Service.
