冀东青龙河太古宙花岗岩绿岩带地质特征

THE GEOLOGICAL FEATURES OF GRANITE GREENSTONE BELTS IN QINGLONG RIVER, JIDONG

青龙河花岗岩 绿岩带形成于新太古代晚期 ,形成环境为古岛弧环境 ,绿岩地体由双山子群、朱杖子群组成。区内褶皱构造、韧性剪切变形带及脆性断裂带十分发育。绿岩地体的形成时间为 2 6 50～ 2 750Ma。花岗质岩石即“TTG”岩系安子岭片麻岩套 ,由四个深成侵入体组成 ,其中柳各庄片麻岩单元直接侵入双山子群鲁杖子组。柳各庄片麻岩多件锆石U Pb一致线年龄数据在 2 510～ 2 550Ma之间。

Qing Long River granite greenstone belts formed in the Neoarchean Era. It made from the environment of the Paleo island arcs. This granite greenstone terrains(GGT) is composed with the Shuangshanzi Group and the Zhuzhangzi Group. Folds, ductile faults and brittle faults are all extremely plentiful in the GGT, formed in the interval 2 650～2 750 Ma, about in late Neoarchean. Granitold rocks, named TTG series, is made up of Anziling gneissic guites, including four plutonic intrusions. Among them, Liugezhuang gneissic rocks intruded directly in Luzhangzi formation of Shuangshansi Group. Several zircon U Pb isotopic ages are collected from Liugezhuang Gneissic rocks. These ages separately are 2 501 Ma, 2 515 Ma, 2 525 Ma, 2 528 Ma, 2 532 Ma, 2 554 Ma etc.