Pumice raft

Pumice raft near Tonga Islands, taken by NASA Earth Observatory, based on data from the Moderate-Resolution Imaging Spectroradiometer Rapid Response System, Goddard Space Flight Center
Pumice stone

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.[1][2]

Astrobiologists have hypothetically linked pumice rafts to the origin of life.[3]

Notable examples

A large pumice raft appeared near New Zealand in August 2012. It was reported to be spread on an area 480 kilometres (300 mi) long, 50 kilometres (30 mi) wide, and riding 60 centimetres (2 ft) above the surface.[4] On 10 August 2012 a raft with an estimated area of 26,000 km2 (10,000 sq mi) was observed near Raoul Island, north-east of New Zealand by the Royal New Zealand Navy.[5][6][7]

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".[8] They went on to witness the ephemeral island known as Home Reef breaching the surface.[9]

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

See also

References

  1. ↑ New Island and Pumice Raft, Tonga, NASA Earth Observatory photo with commentary, August 2006
  2. ↑ Nunn, Patrick D. (2008). Vanished Islands and Hidden Continents of the Pacific. University of Hawai'i Press. p. 59. ISBN 978-0-8248-3219-3.
  3. ↑ Martin D. Brasier, Richard Matthewman, Sean McMahon and David Wacey. "Pumice as a Remarkable Substrate for the Origin of Life" Astrobiology. August 31, 2011
  4. ↑ Space.com, "Source of Mysterious Pumice 'Raft' in Pacific Found, NASA Says", Jeanna Bryner, 14 August 2012
  5. ↑ "Vast volcanic 'raft' found in Pacific, near New Zealand". BBC News. 10 August 2012. Retrieved 10 August 2012.
  6. ↑ "Pumice raft bigger than area of Israel". The Australian. 10 August 2012.
  7. ↑ "'Weirdest thing' floats in South Pacific - CNN.com". CNN. 11 August 2012.
  8. ↑ "Stone sea and volcano". Fredrik and Crew on Maiken. Blogger. 2006-08-17. Retrieved 2008-11-07.
  9. ↑ New Island and Pumice Raft, Tonga, NASA Earth Observatory photo with commentary, November 2006


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