Constraints on flux rates and mantle dynamics beneath island arcs from Tonga-Kermadec lava geochemistry

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doi: 10.1038/39257
Author(s): Turner, Simon; Hawkesworth, Chris
Author Affiliation(s): Primary:
Open University, Department of Earth Sciences, Milton Keynes, United Kingdom
Volume Title: Nature (London)
Source: Nature (London), 389(6651), p.568-573. Publisher: Macmillan Journals, London, United Kingdom. ISSN: 0028-0836 CODEN: NATUAS
Note: In English. 52 refs.; illus., incl. sect., 1 table, sketch map
Summary: Analyses are presented of 58 samples of lavas spanning the length of the Tonga-Kermadec island arc for Mg, Ba, Th, U, Ta, Nd 87Sr/86Sr, 143Nd/144Nd, 206Pb/204Pb, 208Pb/204Pb and 230Th/232Th. Nineteen samples of sediments cored at DSDP Site 204 and lavas from the back-arc island of Niuafo'ou were also analysed. The results provide constraints for physical models of this island arc and may be applicable to arcs in general. Fluid and sediment fluxes from the ocean plate enrich the mantle wedge overlying the subducted plate, but differ in their location, mechanisms and rates. After partial melting, magma extraction occurs via channelled flow through the wedge.
Year of Publication: 1997
Research Program: DSDP Deep Sea Drilling Project
Key Words: 02 Geochemistry; 18 Geophysics, Solid-Earth; Actinides; Alkaline earth metals; Ba/Th; Barium; DSDP Site 204; Deep Sea Drilling Project; East Pacific; Geochemistry; Island arcs; Isotope ratios; Isotopes; Kermadec Islands; Kermadec Trench; Lava; Lead; Leg 21; Magmas; Mantle; Marine sediments; Metals; Nd-144/Nd-143; Neodymium; Oceania; Pacific Ocean; Partial melting; Pb-206/Pb-204; Pb-208/Pb-204; Plate tectonics; Polynesia; Radioactive isotopes; Rare earths; Rates; Sediments; South Pacific; Southeast Pacific; Stable isotopes; Subduction; Ta/Nd; Tantalum; Th-232/Th-230; Thorium; Tonga; Tonga Trench; U-238/Th-232; Uranium; West Pacific Ocean Islands
Coordinates: S245716 S245716 W1740641 W1740641
Record ID: 1997071843
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom