Project/Area Number |
22540427
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Solid earth and planetary physics
|
Research Institution | Hokkaido University |
Principal Investigator |
|
Co-Investigator(Renkei-kenkyūsha) |
TAKEHIRO Shin-ichi 京都大学, 数理解析研究所, 准教授 (30274426)
|
Research Collaborator |
FUKUI Takashi 北海道大学, 大学院・理学院, 大学院理学院
ADACHI Toshitaka 北海道大学, 大学院・理学院, 院生
|
Project Period (FY) |
2010 – 2012
|
Project Status |
Completed (Fiscal Year 2012)
|
Budget Amount *help |
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2012: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2011: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2010: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
|
Keywords | 月 / マグマオーシャン / マントルオーバーターン / マントル対流 / 水星 / 熱史 / 慣性能率 / 火成活動史 / マントル進化 / 火星 / 二分性 / 火成活動 / ダイナモ / 化学成層 |
Research Abstract |
Theoretical and numerical studies on the evolution of the interiors of the Moon and small rocky planets were performed on the basis of the consideration about the variety of raw materials of these bodies by using a model of proto-planetary disk. A series of cumulate rock layers, formed in the early Moon due to cooling and solidification of a magma ocean, should have overturned toward stable structure. During the overturn process, Mg-rich olivine cumulate likely becomes to melt again, which is consistent with the exposure of Mg-rich mafic minerals on the lunar far-side. The present moment of inertia factor of the Moon is explained by the density profile after the completion of overturn. Recent spacecraft data shows that Mercury has a significantly reduced composition enriched in sulfur as well as E-chondrites, which is consistent with our disk model, and also has a thin silicate mantle with thickness less than about 400 km. We performed thermal history simulations considering such a new structure. It is suggested that the liquid core of Mercury is thermally convective until present, allowing dynamo action producing the intrinsic magnetic field of Mercury.
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