1994 Fiscal Year Final Research Report Summary
Study on the material cycle through accretionary prism, boundary between ocean and continent
Project/Area Number |
05452087
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Research Category |
Grant-in-Aid for General Scientific Research (B)
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Allocation Type | Single-year Grants |
Research Field |
Geology
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Research Institution | Shimane University |
Principal Investigator |
TAKASU Akira Geology, Shimane University Associate Professor, 理学部, 助教授 (00183848)
|
Co-Investigator(Kenkyū-buntansha) |
AKASAKA Masahide Geology, Shimane University Associate Professor, 理学部, 助教授 (20202509)
SUZUKI Noriyuki Hokkaido University, Geology, Associate Professor, 理学部, 助教授 (00144692)
SAWADA Yoshihiro Geology, Shimane University Associate Professor, 理学部, 助教授 (80196328)
|
Project Period (FY) |
1993 – 1994
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Keywords | accretionary prism / high-pressure type metamorphic rocks / Sambagawa metamorphic belt / P-T path / garnet / zoning / geochronology |
Research Abstract |
Research of geology and geologic structure has been done in the Sambagawa metamorphic belt, as a typical example of high-pressure type metamorphic belt, in Shikoku, Kii Peninsula, Chubu and Kanto, and rock samples for petrological and geochronological studies have been collected there. Observation of backscattered electron images and chemical analyzes of constituent minerals by the EDS,and P-T paths of the high-pressure type metamorphic rocks have been revealed. Crystal structure of carbonaceous and organic matters within the sedimentary rocks, which were derived from shallow portions of accretionary prism, were analyzed by using X-ray diffraction meter and mass spectrometer. 40Ar/39Ar dating for muscovite concentrates obtained from the Sambagawa schists in Kii Peninsula, and well-defined plateau ages of 75-77 Ma are recorded in the muscovite concentrates. According to the results obtained from this research project the sedimentation and metamorphic evolution in accretionary prism and related areas have been discussed with special reference to the material cycle.
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