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

本研究项目的主要重点是对岛弧和大陆型下地壳的变质和恢复过程进行细致的研究，如日本的高高温和超高温变质地体（Hidaka变质带、Higo变质地体和Kurosegawa变质带）和冈瓦纳碎屑（南极洲、斯里兰卡和印度）。对于国内高、超高温变质地体，重新研究了Hidaka和Higo地体中的石榴石-正辉石麻粒岩和含蓝宝石麻粒岩，以了解其弹性性质过程和相关的花岗岩浆成因。通过地质、岩石学和年代学等方面的研究，将Higo地块的高变质岩与东亚区域变质岩进行了比较。另外对九州黑川带进行了变质和年代学研究。结果表明：发现了温度高达950℃、温度高达1000MPa的超高温基性麻粒岩，利用Um-Nd全岩等时线发现了540Ma的泛非年龄。南极洲、斯里兰卡和印度的冈瓦纳碎片也被处理过。在南极洲东部纳皮尔杂岩的Tonagh岛进行了最详细的太古宙高级变质岩的地质测绘。在完成地质图后，对yht变质岩的变质过程进行了详细的调查，包括P-T-t路径分析和蓝宝石麻粒岩的成因变化。在斯里兰卡，新发现了尖晶石+石英共存的特征。通过Sm-Nd地质年代学的研究，揭示了斯里兰卡基底岩的演化。在对印度东高止山脉高品位变质岩部分熔融过程的研究中，明确了新的岩浆charnockites （c型）及其同位素年龄。部分成果在国内外学术会议上发表了31篇论文和37篇口头和海报报告。少

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