JpGU-AGU Joint Meeting 2020

講演情報

[E] 口頭発表

セッション記号 S (固体地球科学) » S-MP 岩石学・鉱物学

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

コンビーナ:サイモン ウォリス リチャード(東京大学)、永冶 方敬(東京大学大学院理学系研究科)、吉岡 祥一(神戸大学都市安全研究センター)

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

★Invited Papers

*岩森 光1 (1.東京大学・地震研究所)

キーワード:沈み込み、流体、メルト、温度、火成作用、地震学的構造

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.