塔里木盆地三叠纪岩相古地理特征

Characteristics of Triassic lithofacies palaeogeography in Tarim Basin

刘亚雷¹ 胡秀芳² 王道轩³ 赵岩¹ 张强¹ 文磊¹

中国科学院地质与地球物理研究所，北京 100029 浙江大学海洋科学与工程学系，浙江 杭州 310058 合肥工业大学资源与环境工程学院，安徽 合肥 230009

Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, China Department of Ocean Science and Engineering, Zhejiang University, Hangzhou 310058, China School of Resource and Environmental Engineering, Hefei University of Technology, Hefei 230009, China

塔里木盆地三叠纪主要为内陆湖泊的陆相沉积。文中以沉积学理论为指导，以不同地区单井地层-沉积相柱状图解释为基础，对塔里木盆地三叠系进行了沉积相划分和沉积体系分析，并对沉积相类型、古地理环境及沉积相时空演化进行了系统分析。研究认为：早三叠世，塔里木盆地以湖泊和湖泊三角洲体系沉积为主，库车坳陷北部山前发育冲积扇-扇三角洲沉积体系；中三叠世，库车坳陷沉积格局变化不大，盆地内部湖泊面积有所扩大，塔北地区开始发育湖泊三角洲体系；晚三叠世，由于古特提斯洋持续向塔里木板块俯冲，特提斯南缘的羌塘地块与塔里木板块发生碰撞，受此构造运动影响，盆地内部湖盆开始向北退缩，塔北及库车坳陷开始出现含炭沼泽，盆地沉积演化开始向侏罗纪过渡。

In Triassic, Tarim Basin was a continental basin dominated by inland lake. This paper used the sedimentary theory, divided the Triassic sedimentary facies and analyzed the sedimentary system based on the interpretation result of column diagram of stratum-sedimentary facies in different regions of Tarim Basin. It also systematically analyzed the types of sedimentary facies, paleogeographical environment and the time-space evolution of sedimentary facies. Study suggested that in early Triassic, Tarim Basin was dominated by lake and lake-delta systems and developed alluvial fan and fan-delta systems in the submountain region of northern Kuche Depression. In middle Triassic, the change of sedimentary framework is not great and the area of lake within the basin expanded. The lake-delta began to develop in Tabei Area. Up to late Triassic, the lake began to shrink to the north because of the collision of Qiangtang massif and Tarim plate in the southern margin of Tethys. Tabei Area and Kuqa Depression began to appear carbonaceous swamp and the basin had its transition to Jurassic.

10.6056/dkyqt201206004