Generation of silicic melts in the early Izu-Bonin Arc recorded by detrital zircons in proximal arc volcaniclastic rocks from the Philippine Sea

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doi: 10.1002/2017GC006948
Author(s): Barth, A. P.; Tani, K.; Meffre, S.; Wooden, J. L.; Coble, M. A.; Arculus, R. J.; Ishizuka, O.; Shukle, J. T.
Author Affiliation(s): Primary:
Indiana University-Purdue University, Department of Earth Sciences, Indianapolis, IN, United States
Other:
National Museum of Nature and Science, Japan
University of Tasmania, Australia
Stanford University, United States
Australian National University, Australia
Japanese Geological Survey, Japan
Volume Title: Geochemistry, Geophysics, Geosystems - G<sup>3</sup>
Source: Geochemistry, Geophysics, Geosystems - G>3`, 18(10), p.3576-3591. Publisher: American Geophysical Union and The Geochemical Society, United States. ISSN: 1525-2027
Note: In English. 84 refs.; illus., incl. sketch map
Summary: A 1.2 km thick Paleogene volcaniclastic section at International Ocean Discovery Program Site 351-U1438 preserves the deep-marine, proximal record of Izu-Bonin oceanic arc initiation, and volcano evolution along the Kyushu-Palau Ridge (KPR). Pb/U ages and trace element compositions of zircons recovered from volcaniclastic sandstones preserve a remarkable temporal record of juvenile island arc evolution. Pb/U ages ranging from 43 to 27 Ma are compatible with provenance in one or more active arc edifices of the northern KPR. The abundances of selected trace elements with high concentrations provide insight into the genesis of U1438 detrital zircon host melts, and represent useful indicators of both short and long-term variations in melt compositions in arc settings. The Site U1438 zircons span the compositional range between zircons from mid-ocean ridge gabbros and zircons from relatively enriched continental arcs, as predicted for melts in a primitive oceanic arc setting derived from a highly depleted mantle source. Melt zircon saturation temperatures and Ti-in-zircon thermometry suggest a provenance in relatively cool and silicic melts that evolved toward more Th and U-rich compositions with time. Th, U, and light rare earth element enrichments beginning about 35 Ma are consistent with detrital zircons recording development of regional arc asymmetry and selective trace element-enriched rear arc silicic melts as the juvenile Izu-Bonin arc evolved. Abstract Copyright (2017), . American Geophysical Union. All Rights Reserved.
Year of Publication: 2017
Research Program: IODP Integrated Ocean Drilling Program
IODP2 International Ocean Discovery Program
Key Words: 03 Geochronology; 05 Petrology, Igneous and Metamorphic; Absolute age; Actinides; Cenozoic; Chemical composition; Clastic rocks; Dates; Detritus; Expedition 351; Geologic thermometry; IODP Site U1438; Igneous rocks; International Ocean Discovery Program; Izu-Bonin Arc; Kyushu-Palau Ridge; Magmas; Melts; Metals; Nesosilicates; North Pacific; Northwest Pacific; Orthosilicates; Pacific Ocean; Paleogene; Philippine Sea; Sandstone; Sedimentary rocks; Silicate melts; Silicates; Tertiary; Thorium; Titanium; Trace elements; U/Pb; Uranium; Volcanic rocks; Volcaniclastics; Volcanism; West Pacific; Zircon; Zircon group
Coordinates: N150000 N300000 E1450000 E1300000
Record ID: 2018022017
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom, Reference includes data supplied by, and/or abstract, Copyright, American Geophysical Union