Intrusive volcanic rocks in western Pacific forearcs

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doi: 10.1029/GM088p0031
Author(s): Taylor, Rex N.; Marlow, Michael S.; Johnson, Lynn E.; Taylor, Brian; Bloomer, Sherman H.; Mitchell, John G.
Author Affiliation(s): Primary:
University of Southampton, Department of Geology, Southampton, United Kingdom
Rosenstiel School of Marine and Atmospheric Sciences, United States
U. S. Geological Survey, United States
Naval Research Laboratory, United States
University of Hawaii, United States
Boston University, United States
University of Newcastle upon Tyne, United Kingdom
Volume Title: Active margins and marginal basins of the western Pacific
Volume Author(s): Taylor, Brian, editor; Natland, James
Source: Active margins and marginal basins of the western Pacific, edited by Brian Taylor and James Natland. Geophysical Monograph, Vol.88, p.31-43. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0065-8448. ISBN: 978-1-118-66396-7 CODEN: GPMGAD
Note: In English with English summary. 46 refs.; illus., incl. 3 tables, sketch map
Summary: Neogene intrusives were drilled in three Ocean Drilling Program (ODP) holes located in separate segments of the western Pacific intra-oceanic arcs. This paper summarizes the geochemical and physical data from each of the intrusions. New data including K-Ar ages and trace element analyses from the Izu-Bonin sill are presented. Major and trace element data from each intrusion are compared with analyses of corresponding regional volcanics to establish the most likely magmatic source. The intrusives petrographically and geochemically resemble the contemporaneous arc lavas which erupted along the frontal arc 50-100 km to the west. Furthermore, the sills most closely resemble the subjacent volcanoes along the Quaternary arc. They do not resemble backarc basalts nor the spectrum of lava types that erupted in the forearc. The sills were most likely to have been fed from dikes which propagated from the arc through basement rocks at deeper crustal levels.
Year of Publication: 1995
Research Program: ODP Ocean Drilling Program
Key Words: 05 Petrology, Igneous and Metamorphic; 18 Geophysics, Solid-Earth; Absolute age; Basalts; Basement; Cenozoic; Crust; Dates; Dikes; East Pacific; Igneous activity; Igneous rocks; Intrusions; Island arcs; Izu-Bonin Arc; K/Ar; Lau Basin; Leg 126; Major elements; Mariana Trench; Neogene; North Pacific; Northwest Pacific; Ocean Drilling Program; Pacific Ocean; Sills; South Pacific; Southeast Pacific; Tertiary; Trace elements; Volcanic rocks; West Pacific
Coordinates: N305457 N322359 E1405317 E1395039
Record ID: 1995043340
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