*WOW* 800-Mile-Wide Hot Anomaly Found Under Seafloor off Hawaii

Scientists say they've found solid evidence of a giant mass of hot rock under the seafloor in the region. But it's not a plume running straight from the core to the surface—and it's hundreds of miles west of the nearest Hawaiian island.
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"we can't rule out a narrow plume below the island, but the main source comes from a different place. It can't be linked directly below," said geophysicist Robert van der Hilst
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Those signals point to the giant anomaly, about 410 miles (660 kilometers) down: a relatively disklike segment of rock between 540 and 720 degrees Fahrenheit (300 and 400 degrees Celsius) hotter than its surroundings and between 370 miles (600 kilometers) and 1,000 miles (1,600 kilometers) west of the Big Island.

The team suspects the plume is pooling at the boundary between the upper and lower mantle, then snaking its way to the crust below the archipelago before rising to feed Hawaii's volcanic islands.