JpGU-AGU Joint Meeting 2020

Presentation information

[E] Oral

S (Solid Earth Sciences ) » S-MP Mineralogy & Petrology

[S-MP40] Thermal structure of subduction zones: modeling and the rock record

convener:Simon Richard Wallis(The University of Tokyo), Takayoshi Nagaya(Graduate School of Science, The University of Tokyo), Shoichi Yoshioka(Research Center for Urban Safety and Security, Kobe University)

[SMP40-03] Subduction zone processes with fluid and melt: numerical model and observations

★Invited Papers

*Hikaru Iwamori1 (1.Earthquake Research Institute, The University of Tokyo)

Keywords:subduction, fluid, melt, temperature, magmatism, seismic structure

Subduction zone processes involve various geodynamic aspects and the related structures. The thermal structure is one of the important constituents of the system, which affects and is affected by other structures/processes; for instance, the thermal structure controls dehydration of the subducted slab (locus and degree), which affects the viscosity structure of the convecting mantle wedge. In turn, the viscosity structure modifies the flow-thermal structure, which then affects the slab dehydration again to constitute a nonlinear feedback loop as a single geodynamic system. Therefore, these processes and structures have to be considered simultaneously to understand the actual processes in subduction zones.



In this presentation, such consistent models are introduced, including slab dehydration, water-rock interaction including melting, fluid migration-distribution, and viscosity-thermal-flow structure (Horiuchi and Iwamori, 2016, JGR; Nakao et al., 2016, EPSL; 2018, GRL). Then how these models are compared with the observations, such as occurrence of volcanic belt, surface heat flow, seismic velocity and attenuation structures, will be discussed, taking account of the recent knowledge on physical properties of fluid-melt-rock systems.