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<title>UTas ePrints - The Submarine Record of a Large-Scale Explosive Eruption in the Vanuatu Arc: ~1 Ma Efate Pumice Formation</title>
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<meta content="Raos, A.M." name="eprints.creators_name" />
<meta content="McPhie, J." name="eprints.creators_name" />
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<meta content="J.McPhie@utas.edu.au" name="eprints.creators_id" />
<meta content="White, J.D.L." name="eprints.editors_name" />
<meta content="Smellie, J.L." name="eprints.editors_name" />
<meta content="Clague, D.A." name="eprints.editors_name" />
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<meta content="2007-09-06" name="eprints.datestamp" />
<meta content="2008-01-30T04:15:36Z" name="eprints.lastmod" />
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<meta content="The Submarine Record of a Large-Scale Explosive Eruption in the Vanuatu Arc: ~1 Ma Efate Pumice Formation" name="eprints.title" />
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<meta content="pumice breccia, glass shard, submarine explosive eruption,
Vanuatu, eruption-fed density current, hydromagmatic, pyroclastic" name="eprints.keywords" />
<meta content="The Efate Pumice Formation (EPF) is the record of a major explosive eruption that occurred in the Vanuatu arc, southwestern Pacific, at about 1 Ma. The EPF is
the oldest stratigraphic unit of the Efate Island Group and consists of a succession of non-welded, trachydacitic pumice breccia and shard-rich sand and silt beds
with a minimum thickness of ~500 m and a minimum bulk volume of approximately 85 km3. The lower part (Efate Pumice Breccias) of the EPF comprises very thick beds composed almost exclusively of glassy, trachydacitic, pumice fragments with ragged terminations. In contrast, the upper part (Rentabau Tuffs) consists of up to 70 m of well-bedded and well-sorted shard-rich sand and silt. The
clast population of this upper part comprises >95 % glassy or formerly glassy shards, but fossil foraminifera are a ubiquitous and important non-volcanic component.
Some glass shards have blocky, equant shapes and arcuate fracture surfaces, features typically associated with the influence of external water during fragmentation, but most are cuspate and platy bubble-wall shards. Pyroclast morphologies indicate that the Efate Pumice Breccias were largely generated by magmatic-volatile-driven (dry), explosive fragmentation processes, and lithofacies
characteristics indicate deposition in below-storm-wave-base environments, from eruption-sourced, water-supported density currents of waterlogged pumice. The Rentabau Tuffs are interpreted to represent a change to hydromagmatic activity in response to waning discharge that allowed ingress of water (presumably seawater) to the vent(s)." name="eprints.abstract" />
<meta content="2003" name="eprints.date" />
<meta content="published" name="eprints.date_type" />
<meta content="Geophyiscal Monograph" name="eprints.series" />
<meta content="140" name="eprints.number" />
<meta content="American Geophysical Union" name="eprints.publisher" />
<meta content="Washington, DC, USA" name="eprints.place_of_pub" />
<meta content="273-283" name="eprints.pagerange" />
<meta content="10.1029/140GM18" name="eprints.id_number" />
<meta content="UNSPECIFIED" name="eprints.thesis_type" />
<meta content="TRUE" name="eprints.refereed" />
<meta content="0-87590-999-X" name="eprints.isbn" />
<meta content="Explosive Subaqueous Volcanism" name="eprints.book_title" />
<meta content="Allen, S.R., and J. McPhie, Water-settling and resedimentation of submarine rhyolitic pumice at Yali, eastern Aegean, Greece, Journal of Volcanology and Geothermal Research, 95, 285-307, 2000.
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Cashman, K.V., and R.S. Fiske, Fallout of pyroclastic debris from submarine volcanic eruptions, Science, 253, 275-280, 1991.
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Goud Collins, M.R., Volcaniclastic sediments of the North Aoba Basin: depositional processes and geologic history, in
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chronostratigraphy and eustatic cycles, in Sea-level Changes: an integrated approach, edited by C.K. Wilgus, B.S. Hastings, H. Postmentier, et al, pp. 71-108, SEPM Special Publication No. 42, 1988.
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emplacement of the Shinjima Pumice, Shinjima (Moeshima)
Island, Kagoshima Bay, SW Japan, Journal of Volcanology and
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Soh, W., A. Taira, Y. Ogawa, H. Taniguchi, K.T. Pickering, and D.A.V. Stow, Submarine depositional processes for volcaniclastic sediments in the Mio-Pliocene Misaki Formation, Miura Group, central Japan, in Sedimentary Facies in the Active Plate Margin, edited by A. Taira, and F. Masuda, pp. 619-630, Terra Scientific Publishing Company (TERRAPUB), Tokyo, 1989.
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Geothermal Research, 3, 1-37, 1978.
Sparks, R.S.J., H. Sigurdsson, and S.N. Carey, The entrance of pyroclastic flows into the sea, II. Theoretical considerations on subaqueous emplacemant and welding, Journal of Volcanology and Geothermal Research, 7, 97-105, 1980.
Stow, D.A.V., Deep sea processes of sediment transport and deposition, in Sediment transport and depositional processes, edited by K. Pye, pp. 257-291, Blackwell Scientific Publications, Oxford, 1994.
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Wohletz, K.H., Mechanisms of hydrovolcanic pyroclast formation: grain-size, scanning electron microscopy, and experimental studies, Journal of Volcanology and Geothermal Research, 17, 31-63, 1983.
Wohletz, K.H., M.F. Sheridan, and W.K. Brown, Particle size distributions and the sequential fragmentation/transport theory applied to volcanic ash, Journal of Geophysical Research, 94 (B11), 15,703-15,721, 1989." name="eprints.referencetext" />
<meta content="Raos, A.M. and McPhie, J. (2003) The Submarine Record of a Large-Scale Explosive Eruption in the Vanuatu Arc: ~1 Ma Efate Pumice Formation. In: Explosive Subaqueous Volcanism. Geophyiscal Monograph (140). American Geophysical Union, Washington, DC, USA, pp. 273-283. ISBN 0-87590-999-X" name="eprints.citation" />
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<meta content="The Submarine Record of a Large-Scale Explosive Eruption in the Vanuatu Arc: ~1 Ma Efate Pumice Formation" name="DC.title" />
<meta content="Raos, A.M." name="DC.creator" />
<meta content="McPhie, J." name="DC.creator" />
<meta content="260103 Vulcanology" name="DC.subject" />
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<meta content="The Efate Pumice Formation (EPF) is the record of a major explosive eruption that occurred in the Vanuatu arc, southwestern Pacific, at about 1 Ma. The EPF is
the oldest stratigraphic unit of the Efate Island Group and consists of a succession of non-welded, trachydacitic pumice breccia and shard-rich sand and silt beds
with a minimum thickness of ~500 m and a minimum bulk volume of approximately 85 km3. The lower part (Efate Pumice Breccias) of the EPF comprises very thick beds composed almost exclusively of glassy, trachydacitic, pumice fragments with ragged terminations. In contrast, the upper part (Rentabau Tuffs) consists of up to 70 m of well-bedded and well-sorted shard-rich sand and silt. The
clast population of this upper part comprises >95 % glassy or formerly glassy shards, but fossil foraminifera are a ubiquitous and important non-volcanic component.
Some glass shards have blocky, equant shapes and arcuate fracture surfaces, features typically associated with the influence of external water during fragmentation, but most are cuspate and platy bubble-wall shards. Pyroclast morphologies indicate that the Efate Pumice Breccias were largely generated by magmatic-volatile-driven (dry), explosive fragmentation processes, and lithofacies
characteristics indicate deposition in below-storm-wave-base environments, from eruption-sourced, water-supported density currents of waterlogged pumice. The Rentabau Tuffs are interpreted to represent a change to hydromagmatic activity in response to waning discharge that allowed ingress of water (presumably seawater) to the vent(s)." name="DC.description" />
<meta content="American Geophysical Union" name="DC.publisher" />
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<meta content="Smellie, J.L." name="DC.contributor" />
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<meta content="2003" name="DC.date" />
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<h1 class="ep_tm_pagetitle">The Submarine Record of a Large-Scale Explosive Eruption in the Vanuatu Arc: ~1 Ma Efate Pumice Formation</h1>
<p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">Raos, A.M.</span> and <span class="person_name">McPhie, J.</span> (2003) <xhtml:em>The Submarine Record of a Large-Scale Explosive Eruption in the Vanuatu Arc: ~1 Ma Efate Pumice Formation.</xhtml:em> In: Explosive Subaqueous Volcanism. Geophyiscal Monograph (140). American Geophysical Union, Washington, DC, USA, pp. 273-283. ISBN 0-87590-999-X</p><p style="margin-bottom: 1em" class="not_ep_block"></p><table style="margin-bottom: 1em" class="not_ep_block"><tr><td valign="top" style="text-align:center"><a href="http://eprints.utas.edu.au/1874/1/Raos%2C_McPhie_2003.pdf"><img alt="[img]" src="http://eprints.utas.edu.au/style/images/fileicons/application_pdf.png" class="ep_doc_icon" border="0" /></a></td><td valign="top"><a href="http://eprints.utas.edu.au/1874/1/Raos%2C_McPhie_2003.pdf"><span class="ep_document_citation">PDF</span></a> - Full text restricted - Requires a PDF viewer<br />821Kb</td><td><form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/request_doc"><input accept-charset="utf-8" value="2357" name="docid" type="hidden" /><div class=""><input value="Request a copy" name="_action_null" class="ep_form_action_button" onclick="return EPJS_button_pushed( '_action_null' )" type="submit" /> </div></form></td></tr></table><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">The Efate Pumice Formation (EPF) is the record of a major explosive eruption that occurred in the Vanuatu arc, southwestern Pacific, at about 1 Ma. The EPF is
the oldest stratigraphic unit of the Efate Island Group and consists of a succession of non-welded, trachydacitic pumice breccia and shard-rich sand and silt beds
with a minimum thickness of ~500 m and a minimum bulk volume of approximately 85 km3. The lower part (Efate Pumice Breccias) of the EPF comprises very thick beds composed almost exclusively of glassy, trachydacitic, pumice fragments with ragged terminations. In contrast, the upper part (Rentabau Tuffs) consists of up to 70 m of well-bedded and well-sorted shard-rich sand and silt. The
clast population of this upper part comprises >95 % glassy or formerly glassy shards, but fossil foraminifera are a ubiquitous and important non-volcanic component.
Some glass shards have blocky, equant shapes and arcuate fracture surfaces, features typically associated with the influence of external water during fragmentation, but most are cuspate and platy bubble-wall shards. Pyroclast morphologies indicate that the Efate Pumice Breccias were largely generated by magmatic-volatile-driven (dry), explosive fragmentation processes, and lithofacies
characteristics indicate deposition in below-storm-wave-base environments, from eruption-sourced, water-supported density currents of waterlogged pumice. The Rentabau Tuffs are interpreted to represent a change to hydromagmatic activity in response to waning discharge that allowed ingress of water (presumably seawater) to the vent(s).</p></div><table style="margin-bottom: 1em" cellpadding="3" class="not_ep_block" border="0"><tr><th valign="top" class="ep_row">Item Type:</th><td valign="top" class="ep_row">Book Chapter</td></tr><tr><th valign="top" class="ep_row">Keywords:</th><td valign="top" class="ep_row">pumice breccia, glass shard, submarine explosive eruption,
Vanuatu, eruption-fed density current, hydromagmatic, pyroclastic</td></tr><tr><th valign="top" class="ep_row">Subjects:</th><td valign="top" class="ep_row"><a href="http://eprints.utas.edu.au/view/subjects/260103.html">260000 Earth Sciences > 260100 Geology > 260103 Vulcanology</a><br /><a href="http://eprints.utas.edu.au/view/subjects/260100.html">260000 Earth Sciences > 260100 Geology</a></td></tr><tr><th valign="top" class="ep_row">Collections:</th><td valign="top" class="ep_row">UNSPECIFIED</td></tr><tr><th valign="top" class="ep_row">ID Code:</th><td valign="top" class="ep_row">1874</td></tr><tr><th valign="top" class="ep_row">Deposited By:</th><td valign="top" class="ep_row"><span class="ep_name_citation"><span class="person_name">Mrs Katrina Keep</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">06 Sep 2007</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">30 Jan 2008 15:15</td></tr><tr><th valign="top" class="ep_row">ePrint Statistics:</th><td valign="top" class="ep_row"><a target="ePrintStats" href="/es/index.php?action=show_detail_eprint;id=1874;">View statistics for this ePrint</a></td></tr></table><p align="right">Repository Staff Only: <a href="http://eprints.utas.edu.au/cgi/users/home?screen=EPrint::View&eprintid=1874">item control page</a></p>
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