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{{Short description|Floating mass of pumice in the ocean}}
[[File:The eruption of Fukutoku-Oka-no-Ba 05.jpg|thumb|right|Pumice rafts from the eruption of [[Fukutoku-Okanoba]] submarine volcano in 1986, seen from a ship]]
A '''pumice raft''' is a floating raft of [[pumice]] occasionally created by ocean-based [[volcanic]] activity. ▼
[[File:Pumice stone444.jpg|thumb|A piece of pumice]]
▲A '''pumice raft''' is a floating raft of [[pumice]]
Pumice rafts have unique characteristics, such as the highest surface-area-to-volume ratio known for any rock type, long term flotation and beaching in the tidal zone, exposure to a variety of conditions, including dehydration, and an ability to absorb many potentially advantageous elements/compounds. For at least these reasons, [[astrobiologist]]s have proposed pumice rafts as a possible ideal substrate for the [[Abiogenesis|origin of life]].<ref>Martin D. Brasier, Richard Matthewman, Sean McMahon and David Wacey. "Pumice as a Remarkable Substrate for the Origin of Life" Astrobiology. August 31, 2011</ref>
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."<ref>{{cite web |url=http://yacht-maiken.blogspot.com/2006/08/stone-sea-and-volcano.html |title=Stone sea and volcano |work=Fredrik and Crew on Maiken |publisher=[[Blogger (service)|Blogger]] |date=2006-08-17 |accessdate=2008-11-07}}</ref> They went on to witness the ephemeral island known as [[Home Reef]] breaching the surface.<ref>[http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=17610 New Island and Pumice Raft, Tonga], NASA Earth Observatory photo with commentary, November 2006</ref>▼
Biologists
Pumice rafts drifted to [[Fiji]] in 1979 and 1984 from eruptions around Tonga, and some were reportedly 30 kilometers (19 miles) wide.▼
==Notable examples==
▲Biologists suggest that animals and plants have [[Animal migration|migrated]] from island to island on pumice rafts.<ref>[http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=17605 New Island and Pumice Raft, Tonga], NASA Earth Observatory photo with commentary, August 2006</ref><ref>{{cite book|last=Nunn|first=Patrick D.|title=Vanished Islands and Hidden Continents of the Pacific|year=2008|publisher=University of Hawai'i Press|isbn=978-0824832193|page=59}}</ref>
[[Sandy Island, New Caledonia|Sandy Island]], a [[phantom island|non-existent island]] near New Caledonia, was reported in 1876 by the whaling ship ''Velocity'' and subsequently included on some maps well into the 20th century. According to a team of University of Sydney scientists, it is possible that this false report may have been occasioned by pumice rafts being mistaken by the ''Velocity'' for dry land.<ref>{{cite journal |last1=Seton |first1=M. |last2=Williams |first2=S. |last3=Zahirovic |first3=S. |last4=Micklethwaite |first4=S. |date=9 April 2013 |title=Obituary: Sandy Island (1876 –2012) |journal=Eos, Transactions American Geophysical Union |volume=94 |issue=15 |pages=141–142 |bibcode=2013EOSTr..94..141S |doi=10.1002/2013EO150001 |doi-access=free}}</ref><ref>{{cite news |author=Joel Achenbach |date=April 4, 2013 |title=Scientist unravels mystery of Coral Sea's ghostly Sandy Island |newspaper=Washington Post |url=https://www.washingtonpost.com/national/health-science/scientist-unravels-mystery-of-coral-seas-ghostly-sandy-island/2013/04/14/76316606-a508-11e2-8302-3c7e0ea97057_story.html |url-access=subscription |accessdate=May 24, 2021}}</ref>
=== 20th century and onward ===
▲Pumice rafts drifted to [[Fiji]] in 1979 and 1984 from eruptions around Tonga, and some were reportedly {{convert|30
[[File:Pumice raft.jpg|thumb|upright=1.3|Satellite image of a pumice raft near [[Vavaʻu]], Tonga, in August 2006]]
▲Volcanic activity in the South Pacific near
A very large pumice raft appeared near [[New Zealand]] in August 2012. It was reported to be spread on an area {{convert|300|mi|km|order=flip}} long and about {{convert|30|mi|km|-1|order=flip}} wide, with pumice blocks poking up to {{convert|2|ft|cm|-1|abbr=out|order=flip}} above the ocean surface.<ref>Space.com, [http://www.space.com/17102-pumice-raft-pacific-volcano-source.html "Source of Mysterious Pumice 'Raft' in Pacific Found, NASA Says"], Jeanna Bryner, 14 August 2012</ref> On 10 August 2012 [[2012 Kermadec Islands eruption and pumice raft|a raft with an estimated area of {{convert|26000|km2|mi2}}]] was observed near [[Raoul Island]], north-east of New Zealand by the Royal New Zealand Navy. A possible source for the pumice was the July 2012 eruption of Havre [[seamount]] in the Kermadec Islands north of New Zealand.<ref>{{cite news|title=Vast volcanic 'raft' found in Pacific, near New Zealand |url= https://www.bbc.co.uk/news/science-environment-19207810 |publisher=BBC News |accessdate=10 August 2012 |date=10 August 2012}}</ref><ref>{{cite news| url=http://www.theaustralian.com.au/news/breaking-news/undersea-eruption-creates-pumic-raft/story-fn3dxix6-1226447601191 | work=The Australian | title=Pumice raft bigger than area of Israel | date=10 August 2012}}</ref><ref>{{cite news| url=http://edition.cnn.com/2012/08/10/world/asia/floating-pumice/index.html | work=CNN | title='Weirdest thing' floats in South Pacific - CNN.com | date=11 August 2012}}</ref> (''See: [[2012 Kermadec Islands eruption]]).''
In August 2019, a large floating pumice raft covering {{convert|150|km2|sqmi}} was discovered in the tropical Pacific Ocean near [[Late (Tonga)|Late Island]] in the [[Kingdom of Tonga]]. Sailors described a "rubble slick made up of rocks from marble to basketball size such that water was not visible", as well as a smell of sulfur.<ref>{{cite news| url=https://earthobservatory.nasa.gov/images/145490/a-raft-of-rock | work=NASA | title=A Raft of Rock | date=13 August 2019}}</ref><ref>{{cite news| url=https://www.bbc.com/news/world-australia-49469446 | work=BBC | title=Vast 'pumice raft' found drifting through Pacific Ocean | date=26 August 2019}}</ref>
==See also==
*[[Floating island]]▼
*[[Curacoa volcano]]
▲*[[Floating island]]
*[[Lava balloons]]
==References==
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==External links==
*[
*[https://volcano.si.edu/showreport.cfm?doi=10.5479/si.GVP.BGVN200609-243080 Pumice rafts in Fiji produced by the eruption of Home Reef volcano, Tonga in 2006]
[[Category:Geology]]▼
[[Category:Volcanoes]]
[[Category:Volcanology]]
[[Category:Rafts]]
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