Pumice raft

A pumice raft is a floating raft of pumice occasionally created by ocean-based or near-ocean volcanic activity.

Biologists suggest that animals and plants have migrated from island to island on pumice rafts.

Astrobiologists have hypothetically linked pumice rafts to the origin of life.

A large pumice raft appeared near New Zealand in August 2012. It was reported to be 300 miles (480 km) long, 30 miles (48 km) wide, and riding two feet (sixty centimeters) above the surface. On 10 August 2012 a raft with an estimated area of 10,000 sq miles was observed near Raoul Island, north-east of New Zealand by the Royal New Zealand Navy.

Volcanic activity in the South Pacific near Tonga on August 12, 2006 caused the emergence of a new island. The crew of the Maiken, a yacht that had left the northern Tongan islands group of Vava'u in August, reported that they had seen streaks of light, porous pumice stone floating in the water—and then had "sailed into a vast, many-miles-wide belt of densely packed pumice". They went on to witness the ephemeral island known as Home Reef breaching the surface.

Pumice rafts drifted to Fiji in 1979 and 1984 from eruptions around Tonga, and some were reportedly 30 kilometers (19 mi) wide.

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