武当山地区中上元古界及成岩构造环境的地球化学论证

THE MIDDLE-UPPER PROTEROZOIC SUBERATHEM AND GEOCHEMICAL DEMONSTRATION OF ITS DIAGENETIC TECTONIC SETTING IN WUDANGSHAN AREA, CHINA

通过对分布于武当山地区的中上元古界武当山群,耀岭河群的变火山岩、变沉积岩的岩石学、岩石化学,微量元素地球化学和稀土元素地球化学及有关图解的综合研究和应用,笔者认为武当山群的成岩环境为古岛弧,而耀岭河群的成岩环境为古陆缘裂谷。中晚元古代期间,武当山地区构造演化经历了从古岛弧向古陆缘裂谷转化的历程。

Through studies of petrology, pctro-chemistry, trace clement geochemistry and rare earth element geochemistry and the application of concernbd trace clement diagrams to meta-volcanic and recta-sedimentary rocks of the middle-upper Protorozoic suberathem, the Wudangshan and Yaolinghe Groups in Wudangshan area, the author points out that the diagenetic tectonic setting of the Wudangshan Group is probably an paleo-island arc, and that of the Yaolinghe Group, a paleo—continental margin rift. During the middle-upper Proterozoie, the tectonic evolution experienced a change from a paleo-island arc to a paleo-continental margin rift in this area.