塔里木盆地南部玛东早古生代褶皱-冲断带  

Madong Early Paleozoic fold-thrust belt in the southern Tarim Basin

作　　者：杨海军[1] 李曰俊[2] 李勇[1] 陈才[1] 曾昌民[1] 文磊[2] 师骏[1] 张强[2] 

机构地区：[1]中国石油塔里木油田分公司,库尔勒841000 [2]中国科学院地质与地球物理研究所,北京100029

出　　处：《岩石学报》2016年第3期815-824,共10页Acta Petrologica Sinica

基　　金：国家科技重大专项(2011ZX05028-003、2011ZX05003-004)资助

摘　　要：玛东褶皱-冲断带位于塔里木盆地南部,走向NE-SW,由NW向SE方向冲断。褶皱冲断带发育于寒武-奥陶系,以中寒武统膏-盐层为主滑脱面。中志留统及其以上地层不整合于褶皱冲断带之上。它是世界上保存最好的早古生代褶皱冲断带之一。根据卷入变形最新地层、不整合于褶皱-冲断带之上的最老地层和上奥陶统上部的生长地层,玛东褶皱-冲断带的变形时间为晚奥陶世-早志留世。玛东褶皱-冲断带与其东南侧的塘南褶皱-冲断带同为塔里木盆地南缘早古生代前陆褶皱-冲断带的组成部分,塘南褶皱-冲断带是该早古生代前陆褶皱-冲断带主体的残余,其向NW的主冲断方向代表该前陆褶皱-冲断带的主冲断方向;玛东褶皱-冲断带是该早古生代前陆褶皱-冲断带的前锋,其向SE的冲断具有反冲性质。它们是昆仑早古生代造山作用的重要记录,也是昆仑早古生代碰撞造山带的组成部分,现今保存最好的部分。Madong fold-thrust belt,strike NE-SW and thrust southeastward,is located in the southern Tarim Basin. It is one of the best preserved Early Paleozoic fold-thrust belts in the world,with the fold-thrust structure developed in Cambrian and Ordovician strata,the Middle Cambrian gypsum-salt layer as the main décollement surface,the Middle Silurian and the above strata unconformably overlie the fold-thrust belt. According to the youngest strata involved in fold-thrust structure,the oldest strata covered on the fold-thrust belt and the growth strata of the upper part of the Upper Ordovician,we inferred that the deformation time of Madong fold-thrust belt was Late Ordovician-Early Silurian. Madong fold-thrust belt and Tangnan fold-thrust belt in the southeast side both are part of the Kunlun（ southern margin of Tarim Basin） Early Paleozoic foreland fold-thrust belt： Tangnan fold-thrust belt is the residual of the foreland fold-thrust belt,with its thrust direction northwestward on behalf of the main thrust direction of the foreland fold-thrust belt;Madong fold-thrust belt is the front of the foreland fold-thrust belt,with its thrust direction southeastward as the back-thrust direction of the foreland fold-thrust belt. They are both important records of Kunlun Early Paleozoic Orogeny,and the best preserved part of the Kunlun Early Paleozoic collisional orogenic belt.

关 键 词：玛东褶皱-冲断带 塘南褶皱-冲断带 早古生代(前陆)褶皱冲断带 晚奥陶世-早志留世 塔里木盆地南部 昆仑造山带 

分 类 号：P542.2[天文地球—构造地质学]