1991 Fiscal Year Final Research Report Summary
Experimental Studies on Chemical Structure of the Deep Mantle and Its formation Processes.
Grant-in-Aid for General Scientific Research (A)
|Allocation Type||Single-year Grants|
|Research Institution||Tohoku University|
ONUMA Kosuke Prof. of Faculty of Science, Tohoku University, 理学部, 教授 (50000865)
HASENAKA Toshiaki Instractor of Faculty of Science, Tohoku University, 理学部, 助手 (50202429)
FUJIMAKI Hirokazu Associate Prof. of Faculty of Science, Tohoku Univ., 理学部, 助教授 (90133933)
AOKI Ken-ichiro Prof. of Faculty of Science, Tohoku University, 理学部, 教授 (00004276)
KATO Takumi Instractor of Faculty of Science, Tohoku University, 理学部, 助手 (90214379)
OHTANI Eiji Associate Prof. of Faculty of Science, Tohoku University, 理学部, 助教授 (60136306)
|Project Period (FY)
1989 – 1991
|Keywords||Mantle Minerals / Phase equilibria of silicate at high Pressure / Partioning of elements between mantle and core minerals / Phase transition at high pressure / Martian Interior / Density of Minerals / 珪酸塩メルトー鉱物の密度逆転|
Experimental studies on the earth matrials have been performed using the multi-anvil type high pressure apparatus with the following results during the term of project.
1. Phase relations among the mantle minerals above 8 GPa : Phase equilibrium diagrams have been determined for the system (1) forstbrite-anorthite-diopside, (2) diopside-enstatite, and (3) forsterite-pyrope. Pressure dependence of the composition of the liquid produced by partial melting and the melting behavior of the minerals present were elucidated.
2. Transitions and phase equilibria of the core materials : (1) Transitions of Fe were determined by the electric resistance method developed in our laboratory. (2) Phase equilibria of the system Fe-Fes were determined at 8 GPa.
3. Partitioning of elements between core and mantle materials : Partitioning of some elements between mantle minerals, silicate melts, and metal iron above 10 GPa was determined, and the relationships between abundance of these elements and core-mantle equilibrium odel were examined on the basis of the experimental data.
4. In-situ observation of MgSiO_3 transition by X-ray diffraction analysis : Transition of clinopyroxene structure - Mg_2SiO_4 spinel +stishovite - ilmenite structure were determined at 20 - 27 GPa.
5. Martian Interior model ; High pressure-high temperature experiments were carried out on a estimated martian mantle composition and a structure model of the martian interior were presented, based on the experimental results.
6. Density of peridotite melt at high pressures : Pressure dependence of forsterite and peridotite melt were examined with the result suggesting that density cross over between forsterite and Fe-rich peridotite melt is not probable.
Research Products (12results)