Gigantic Pumice Raft from Underwater Eruption Is on a Wild Ride Across the Pacific Ocean

“We know so little about the seafloor,” said Jackie Caplan-Auerbach, a seismologist and volcanologist at Western Washington University.

It’s often said that 70 or 80 percent of the world’s volcanism happens on the seafloor, but this number is sketchy guesstimate, Caplan-Auerbach said. We actually don’t know how much volcanism is going on down there, but our knowledge of plate tectonics and seafloor surveys suggests that it’s a lot. Sadly, unless we stumble on it by chance, it’s often never caught in the act.