Minute examination of metamorphic and restite-formation processes in the Island-arc and continental lower crusts

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The main focus of this research program was the minute study of metamorphic and restiteformation processes among the island-arc and continental type lower crusts as seen the high-and ultrahigh-temperature metamorphic terrane in Japan (Hidaka metamorphic belt, Higo metamorphic terrane and Kurosegawa belt) and in Gondwana fragments (Antarctica, Sri Lanka and India).For the domestic high-and ultrahigh-temperature metamorphic terranes, garnet-orthopyroxene granulite and sapphirine-bearing granulite from the Hidaka and Higo terranes were re-examined to understand the process of restitic natures and related granitic magma genesis. Especially in the Higo terrane, the high-grade metamorphic rocks compared with East Asian regional metamorphic rocks through the geological, petrological and geochronological investigations. Another metamorphic and chronological studies also carried out for the Kurosegawa belt in Kyushu. The results include the finding of UHT-mafic granulite up to 950℃ and 1000MPa … More and Pan African age of 540Ma using Um-Nd whole rock isochron.Antarctica, Sri Lanka, and India as the Gondwana fragments were also treated. The most detailed geological mapping for the Archean high-grade metamorphic terrane have done at Tonagh Island in the Napier Complex, East Antarctica. After the completion of the geological map, detailed investigations of metamorphic process of YHT-metamorphic rocks including P-T-t path analyses and variety on the origin of sapphirine granulites were also carried our In Sri Lanka, characteristic spinel+quartz coexistence was newly found. It shed a light on the evolution of Sri Lankan basement rocks with studies of Sm-Nd geo chronology. And during the examination of partial melting process of high-grade metamorphic rocks in Eastern Ghats, India, new magmatic charnockites (C-type) and their isotopic ages were clearly identified.A part of the results were published as 31 articles of journal papers and 37 oral and poster presentations, not only domestic but also international meetings. Less