But as the team conducted its research, it found high quantities of an isotope of helium, which comes almost exclusively from mantle, Loose said.
"When you find helium-3, it's like a fingerprint for volcanism. We found that it is relatively abundant in the seawater at the Pine Island shelf.
"The volcanic heat sources were found beneath the fastest moving and the fastest melting glacier in Antarctica, the Pine Island Glacier," Loose said. "It is losing mass the fastest."
He said the amount of ice sliding into the ocean is measured in gigatons. A gigaton equals 1 billion metric tons.