Watch: An Underwater Volcano Turned Japan's Coastline Into Waves of Pumice

But the story of Fukutoku-okanoba doesn’t stop there.

Photo: Earth Observatory NASA

On August 17, another satellite image showed vast rafts of pumice floating around the caldera of the volcano. And they kept floating until, in late October, they showed up on Japan’s coastlines.

According to the Global Volcanism Program, the pumice arrived first at Kitadaito Island on October 8 and later made its way to the Okinawa Prefecture, as well as several ports in the Kagoshima prefecture on the southern part of island of Kyushu.

Pumice is a very porous rock that’s formed during explosive volcanic eruptions. Pumice floats on water, and according to NASA’s Earth Observatory, “Rafts of the rock can drift in the ocean for months or even years.”

The tons of floating pumice from Fukutoku-okanoba has wrecked havoc every where it’s drifted. It’s clogged harbors and beaches, killed marine wildlife, damaged boats and engines, and severely disrupted the fishing industry, The Guardian reports.

Photos taken by Síle Nic Chormaic, an Irish Physicist living in Japan, show the extent of the pumice invasion.

Chormaic also captured a video of her running her hand through the unbelievably thick layer of pumice in the water.

Local authorities have started clearing the tens of tons of pumice with diggers. The clean-up operation is expected to take weeks.