藏北羌塘中部晚古生代增生杂岩的发现及其地质意义

Discovery and geologic significance of Late Paleozoic accretionary complexes in central Qiangtang, northern Tibet, China

西藏中部羌塘变质岩带发育复理石碎屑建造和片理化玄武岩建造,都经历了强烈的构造置换作用;还发育早—晚古生代大理岩岩片、无根勾状褶皱和大理岩与蓝片岩组成的同斜褶皱,不同时代的榴辉岩呈岩块出露。这些地质体呈岩片产出,经历了多期构造叠加和置换,原岩总体为碎屑岩、泥质岩、硅质岩、碳酸盐岩及枕状玄武岩、辉长岩建造。宏观上发育明显的区域性置换面理,为典型的造山带增生杂岩。

Relevant studies have shown that the flysch clastic and schisteous basalt formation of Qiangtang metamorphic belt, central Tibet have commonly experienced a strong structural transposition. Also there are many early-late Paleozoic marble slices, rootless hook-shaped folds and isoclinal folds consist of marble and glaucophane schist. Eclogites formed at various ages exposed as blocks. These geologic bodies occur in slices and have experienced many phases of structure superposition and transposition. Original rocks in general are clastic rock, mudstone, siliceous rocks, carbonate rocks, pillow basalt and gabbro. Macroscopic regional foliation replacement indicates that this is typical orogenic zone accretionary complexes .