A record of spontaneous subduction initiation in the Izu-Bonin-Mariana arc

Research output: Contribution to journalArticlepeer-review

Authors

  • Richard J. Arculus
  • Osamu Ishizuka
  • Kara A. Bogus
  • Michael Gurnis
  • Rosemary Hickey-Vargas
  • Mohammed H. Aljahdali
  • Alexandre N. Bandini-Maeder
  • Andrew P. Barth
  • Philipp A. Brandl
  • Laureen Drab
  • Rodrigo Do Monte Guerra
  • Morihisa Hamada
  • Fuqing Jiang
  • Kyoko Kanayama
  • Sev Kender
  • Yuki Kusano
  • He Li
  • Lorne C. Loudin
  • Kathleen M. Marsaglia
  • Anders McCarthy
  • Sebastién Meffre
  • Antony Morris
  • Martin Neuhaus
  • Ivan P. Savov
  • Clara Sena
  • Frank J. Tepley
  • Cees Van Der Land
  • Gene M. Yogodzinski
  • Zhaohui Zhang

Colleges, School and Institutes

External organisations

  • The Australian National University
  • Japan Agency for Marine-Earth Science and Technology
  • The University of Texas at Brownsville and Texas Southmost College, Brownsville, Texas 78520, USA
  • Division of Geological and Planetary Sciences, California Institute of Technology, MC 2520-21
  • Florida International University
  • Florida State University
  • The University of Western Australia
  • Indiana University-Purdue University Indianapolis
  • Friedrich-Alexander-Universität Erlangen-Nürnberg
  • Lamont-Doherty Earth Observatory
  • University of Vale Do Rio Dos Sinos
  • Chinese Academy of Sciences
  • Kanazawa University
  • British Geological Survey
  • Guangzhou Institute of Geochemistry Chinese Academy of Sciences
  • University of New Hampshire Durham
  • California State University Northridge
  • University of Lausanne
  • University of Tasmania
  • University of Plymouth
  • Technische Universität Braunschweig
  • University of Leeds
  • University of Aveiro
  • Oregon State University
  • Newcastle University
  • Division of Rheumatology and Immunology, Medical University of South Carolina, Charleston, South Carolina, USA.
  • Nanjing University

Abstract

The initiation of tectonic plate subduction into the mantle is poorly understood. If subduction is induced by the push of a distant mid-ocean ridge or subducted slab pull, we expect compression and uplift of the overriding plate. In contrast, spontaneous subduction initiation, driven by subsidence of dense lithosphere along faults adjacent to buoyant lithosphere, would result in extension and magmatism. The rock record of subduction initiation is typically obscured by younger deposits, so evaluating these possibilities has proved elusive. Here we analyse the geochemical characteristics of igneous basement rocks and overlying sediments, sampled from the Amami Sankaku Basin in the northwest Philippine Sea. The uppermost basement rocks are areally widespread and supplied via dykes. They are similar in composition and age-as constrained by the biostratigraphy of the overlying sediments-to the 52-48-million-year-old basalts in the adjacent Izu-Bonin-Mariana fore-arc. The geochemical characteristics of the basement lavas indicate that a component of subducted lithosphere was involved in their genesis, and the lavas were derived from mantle source rocks that were more melt-depleted than those tapped at mid-ocean ridges. We propose that the basement lavas formed during the inception of Izu-Bonin-Mariana subduction in a mode consistent with the spontaneous initiation of subduction.

Details

Original languageEnglish
Pages (from-to)728-733
Number of pages6
JournalNature Geoscience
Volume8
Issue number9
Early online date24 Aug 2015
Publication statusPublished - 1 Sep 2015

ASJC Scopus subject areas