Massive Extinct Volcano Discovered Beneath Pacific Ocean

newly discovered Pacific Ocean seamount.
The newly discovered seamount rises up some 3,600 feet (1,100 meters) from the seafloor near the Johnston Atoll, at a depth of about 16,730 feet (5,100 m) under the Pacific Ocean.
(Image credit: Image courtesy of the Center for Coastal and Ocean Mapping/Joint Hydrographic Center.)

Lurking some 3.2 miles (5.1 kilometers) beneath the Pacific Ocean, a massive mountain rises up from the seafloor, say scientists who discovered the seamount using sonar technology.

The seamount is about two-thirds of a mile high (1.1 kilometers), researchers said. Seamounts, rocky leftovers from extinct, underwater volcanoes, are found on ocean floors around the world. The newly discovered seamount is about 186 miles (300 km) southeast of Jarvis Island, an uninhabited island in a relatively unexplored part of the South Pacific Ocean, experts said.

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Laura Geggel
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Laura is the managing editor at Live Science. She also runs the archaeology section and the Life's Little Mysteries series. Her work has appeared in The New York Times, Scholastic, Popular Science and Spectrum, a site on autism research. She has won multiple awards from the Society of Professional Journalists and the Washington Newspaper Publishers Association for her reporting at a weekly newspaper near Seattle. Laura holds a bachelor's degree in English literature and psychology from Washington University in St. Louis and a master's degree in science writing from NYU.