Session outline
Solid Earth Sciences(S)
Session Sub Category Complex & General(CG)
Session ID S-CG08
Title Geodynamics of off-arc volcanism and back-arc opening
Short title Geodynamics of off-arc volcanism
Convener Name Hitoshi Kawakatsu
Affiliation Earthquake Research Institute, University of Tokyo
Co-convener 1. Name Steve Grand
Affiliation University of Texas
Co-convener 2. Name John Chen
Affiliation Peking Universtiy
Co-convener 3. Name Thorsten W. Becker
Affiliation University of Southern California
International Symposium 'International Symposium' in addition to Scientific session.
Language English
Scope Deployments of large-scale, high-density seismic arrays around the world have started to reveal regional-scale, upper mantle structures with unprecedented detail. Such improved imaging is crucial to elucidating long-standing tectonic questions such as the links between surface tectonics and volcanism. For example, NECESSArray consists of 120 broadband stations deployed in northeast China (2009-2011). The region is known to display puzzling, Cenozoic intraplate and off-arc volcanism, but the relationship with the stagnant slab beneath the Japan Sea, if any, has been debated. Preliminary tomographic images from NECESSArray reveal an unexpected result; the absence of a long-tailed, stagnant slab beneath the chain of volcanoes, suggesting a possible link of volcanism either to the mantle transition zone, or the lower mantle. This finding opens a new discussion on the origin of off-arc volcanism and back-arc opening in the wider context of global geodynamics. We solicit contributions from geologists, petrologists, geochemists, geophysicists, geodynamicists, and seismologists working on related problems in the NW Pacific subduction zone and other similar, or contrasting, subduction zone settings world wide.
Type of presentation Oral and Poster presentation
Invited papers Richard M. Allen (UC Berkeley, USA)
Wei Leng (U Science and Technology, Hefei, China)
Tetsuya Sakuyama (IFREE/JAMSTEC)
Masayuki Obayashi (IFREE/JAMSTEC)