HR: 17:45h
AN: V44A-08 INVITED     [Abstracts]
TI: Systematic Survey of the Kermadec-Tonga Intra-oceanic arc Between 1999 and 2004: a Significant Source of Diverse Submarine Hydrothermal Emissions
AU: * de Ronde, C E
EM: cornel.deronde@gns.cri.nz
AF: Institute of Geological and Nuclear Sciences, 30 Gracefield Road, Lower Hutt, 6009 New Zealand
AU: Massoth, G J
EM: g.massoth@gns.cri.nz
AF: Institute of Geological and Nuclear Sciences, 30 Gracefield Road, Lower Hutt, 6009 New Zealand
AU: Baker, E T
EM: edward.baker@noaa.gov
AF: Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, 7600 Sand Point Way NE, Seattle, WA 98115-6349 United States
AU: Lupton, J E
EM: john.e.lupton@noaa.gov
AF: Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, 2115 Marine Science Drive, Newport, OR 97365-5258 United States
AU: Arculus, R J
EM: richard.arculus@anu.edu.au
AF: Australian National University, Department of Geology, Canberra, ACT 0200 Australia
AU: Wright, I C
EM: i.wright@niwa.co.nz
AF: National Institute of Water & Atmospheric Research, Greta Point, Wellington, 6009 New Zealand
AU: Stoffers, P
EM: pst@gpi.uni-kiel.de
AF: University of Kiel, Olshausenstr. 40, Kiel, D-24118 Germany
AU: Ishibashi, J
EM: ishi@geo.kyushu-u.ac.jp
AF: Kyushu University, Dept. of Earth and Planetary Sciences, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 000000 Japan
AU: Walker, S L
EM: sharon.l.walker@noaa.gov
AF: Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, 7600 Sand Point Way NE, Seattle, WA 98115-6349 United States
AU: Greene, R R
EM: ronald.r.greene@noaa.gov
AF: Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, 2115 Marine Science Drive, Newport, OR 97365-5258 United States
AU: Faure, K
EM: k.faure@gns.cri.nz
AF: Institute of Geological and Nuclear Sciences, 30 Gracefield Road, Lower Hutt, 6009 New Zealand
AU: Takai, K
EM: kent@jamstec.go.jp
AF: Jamstec, 2-15 Natsushima-cho, Yokosuka, 237-0061 Japan
AB: The 1999 NZAPLUME cruise was the first of several expeditions to systematically locate, and chemically characterise, submarine hydrothermal vents associated with arc volcanoes of the southern part the Kermadec-Tonga intra-oceanic arc system. This was followed by the 2002 NZAPLUME II and 2004 NZAPLUME III cruises to the mid- and northern-sections of the Kermadec arc, respectively, and the 2001 TELVE cruise to the southern part of the Tonga (Tofua) arc. Combined, $\sim$1,800 km of this arc system have been mapped, including $\sim$60 major volcanoes and numerous subordinate volcanic edifices, making this the longest continuous stretch of intra-oceanic arc to be surveyed for hydrothermal emissions. Most of the volcanoes are simple cones although $\sim$25% are caldera volcanoes with their compositions ranging from basalt through rhyo-dacite. Results from the NZAPLUME I and II cruises show 16 of the 26 major volcanoes surveyed are hydrothermally active, while 7 of 19 are active along the Tongan section of the arc, a $\sim$50% frequency of venting. Depths to venting range from $\sim$120 m to $\sim$1,650 m. Chemical analysis of the hydrothermal plumes shows a large range in composition, including different compositions for plumes from vent sites at the same volcano, with indications locally of a magmatic fluid component. An expedition in Oct./Nov. 2004 by the deep-sea submersible Shinkai 6500 will enable vent sites at Brothers and Healy volcanoes to be mapped and mineralization, animals to be sampled.
DE: 8424 Hydrothermal systems (8135)
DE: 8135 Hydrothermal systems (8424)
DE: 4825 Geochemistry
DE: 3035 Midocean ridge processes
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2004 AGU Fall Meeting