资源调查与环境Issue(2)：79-88,10.
钦杭结合带加里东期榴闪岩超高压变质作用研究∗
Discussion on the ultrahigh-pressure metamorphism of Caledonian garnet amphibolite in the Qinzhou-Hangzhou joint belt
摘要
Abstract
By studying on the chronology,mineralogy and metamorphism of Caledonian garnet amphib-olite first discovered in the Qinzhou-Hangzhou joint belt,it is concluded that the garnet amphibolite, which possesses typical clockwise P-T-t path including amphibolite-facies prograde metamorphism in early stage,eclogite-facies(UHP)peak metamorphism in middle stage and amphibolite-facies retrogressive met-amorphism in late stage,yields a metamorphic age of 454±4 Ma.The mineral assemblage of the amphibo-lite-facies prograde metamorphism in early stage is amphibole(Amp)+plagioclase(Pl)+quartz(Qtz)with temperature of 71 9℃~795℃ and pressure of 7.56Kpa~8.30Kpa,the eclogite-facies(UHP)peak meta-morphism in middle stage has the mineral assemblage of garnet(Gt)+ akmite (retrograde to diopside+al-bite)±Qtz with temperature of 668℃~821℃ and pressure of 26.42 Kpa~33.46 Kpa,the amphibolite-fa-cies retrogressive metamorphism in late stage is composed of Gt + Amp + Pl ± Qtz with temperature of 61 1℃~854℃ and pressure of 4.76 Kpa~9.30 Kpa.Combined with the previous studies,it is proposed that the Qinzhou-Hangzhou joint belt had undergone evolutionary process of eclogite-facies(UHP)meta-morphism,granulite-facies retrogressive metamorphism and amphibolite-facies retrogressive metamor-phism in Caledonian.The first discovery of the Caledonian UHP metamorphism in the Qinzhou-Hangzhou joint belt indicates that the collision between Cathaysia and Yangtzs blocks occurred in Caledonian.关键词
超高压变质/顺时针P-T-t轨迹/榴闪岩/加里东期/钦杭结合带Key words
ultrahigh-pressure metamorphism/clockwise P-T-t path/garnet amphibolite/Caledonian/the Qinzhou-Hangzhou joint belt分类
天文与地球科学引用本文复制引用
姜杨,陈志洪,谭桂丽,杨祝良,周效华,袁强,余明刚,赵希林,段政..钦杭结合带加里东期榴闪岩超高压变质作用研究∗[J].资源调查与环境,2015,(2):79-88,10.基金项目
中国地质调查局项目(项目编号:12120114005801和12120113065200)和国家自然科学基金青年基金项目(项目编号:41002024)资助。 （项目编号:12120114005801和12120113065200）
