Superheated Magma Underwater

Superheated magma slowly leaks from a crack in the seafloor.

Superheated magma, about 2,200 degrees Fahrenheit, glows orange as it slowly leaks from cracks along the six-mile long active rift zone of the West Mata Volcano in the Pacific Ocean near Fiji. The slow-leaking magma doesn't erupt, but bubbles out and solidifies to form pillow basalts, a type of rock commonly found at volcano sites and in the Earth's crust. The volcano's top is nearly a mile below the ocean surface (1165 meters / 3882 feet), and its base descends to nearly two miles (3000 meters / 9842 feet) deep. Watch a video of submarine volcanoes erupting.