Undersea Eruption Spews Ash and Steam Near Tonga

Top image shows the towering column of steam and ash as visible from the waterfront of Nuku'alofa, capital of Tonga. The lower image was taken during an overflight of the eruption.

A spectacular undersea eruption was clearly visible to residents on the Tongan island of Tongatapu on Wednesday morning, with steam soaring thousands of feet into the sky above the South Pacific.

The eruption occurred in a cluster of 36 known undersea volcanoes, according to the head of Tonga’s geological service, Keleti Mafi.

"It's a very significant eruption, on quite a large scale," he told The Associated Press. But Mafi said the eruption was of no apparant danger to residents of Tongatapu.

Matangi Tonga reports officials believe the eruption may be linked to a magnitude 4.4 tremor that struck the previous Friday in the same area.

Some residents said they saw steam and ash columns on Monday morning, following a series of other sharp tremors felt onshore. But many other residents of Tongatapu didn’t report seeing evidence of the eruption until after dawn on Wednesday.

A large quantity of pumice ejected into the sea by the eruption was expected to reach the beaches of the nearby Fiji Islands within a short time, Mafi said.

An eruption off the western end of Tongatapu in 2002 created two small volcanic islands, which disappeared beneath the water several weeks later.

In August 2006, travelers yachting through the Tonga Islands discovered pumice floating on the ocean surface. The volcanic debris resulted from an underwater eruption of the marine volcano Home Reef.

Top photo: Pesi Fonua
Bottom photo: Trevor Gregory