Research on the Sedimentary Characteristics of Permian in Yecheng-Hetian Area of Southwest Tarim Basin

On the basis of the seniors' study,we research on the strata and sedimentary characteristics of Permian in Yecheng-Hetian area of southwest Tarim basin by using field geologic investigation,core observation and sample test.We have Clarified the project of stratigraphy division and correlation of Permian in this area.The early Permian,it inherited the extensive transgression of carboniferous period,was the peak period the development of carbonate platform.In the middle Permian,marine regressed from east to west,and it developed interbedded marine-continental facies deposits.In the later Permian,crust uplift,the land descended from west to east,and marine regressed entirely,only developed continental deposits in submountain region of Hetian area.There are three sedimentary facies modes,including carbonate deposits sedimentary facies mode,mixed continental shelf deposit sedimentary facies mode and clastic rocks deposit sedimentary facies mode.