[M-GI40] 計算科学による惑星形成・進化・環境変動研究の新展開

[MGI40-05] マントル対流の数値モデリング〜月・プレートテクトニクス・スーパー地球を例にして〜

*亀山 真典^1,2、小河 正基^3,2、宮腰 剛広²、柳澤 孝寿² (1.国立大学法人愛媛大学地球深部ダイナミクス研究センター、2.国立研究開発法人海洋研究開発機構、3.国立大学法人東京大学大学院総合文化研究科)

キーワード：数値シミュレーション、地球型惑星、マントル対流

We are developing advanced numerical models of mantle convection of solid rocks, in order to deepen the insights into the thermo-chemical evolution of the mantles of terrestrial bodies. The key ingredients in our models include the effects of mantle magmatism, plate tectonics, and adiabatic compression. The mantle magmatism is modeled by the generation of liquid phase (magma) owing to the pressure-release melting induced by ascending flows of solid-state convection and the motion of the generated magma as a permeable flow through the solid matrix driven by a buoyancy due to the density difference between the solid and the liquid phases. The coherent motion of tectonic plates is, on the other hand, helped by the narrow zones of low viscosity within the highly viscous "lithosphere" along the top cold surface generated by the stress-history-dependent rheology. In addition, the adiabatic change in temperature, which is caused by the changes in volume of fluid parcels during their vertical motion, is expected to strongly affect the convecting motion particularly in the mantles of massive super-Earths. In this presentation, we will show the current status and outcrops of our attempts, together with some examples of our experiments running on massive (super)computers.