羌塘盆地查郎拉地区中新生界沉积相研究

油气的生成与聚集和沉积相有极为密切的关系，为评价羌塘盆地查郎拉地区中新生界含油气前景，在野外遥感调研的基础上，系统研究了该地区中新生界的沉积环境．其岩石类型主要为碎屑岩和碳酸盐岩两大类．划分出浅海相、碳酸盐台地相、滨岸相、三角洲相、河口湾相、河流相、冲积扇相七个大相、１８ 个亚相和若干微相，各时代地层的沉积相表现为：①晚三叠世以大面积海陆过渡相占主导地位，总体形成海退沉积旋回；②中侏罗世浅海相沉积较发育，晚侏罗世以海陆过渡相沉积为主；③白垩纪岩相古地理存在早晚差异，早期为残留海背景下的局限碳酸盐台地沉积，晚期为山麓冲积扇沉积．

Mesozoic-Cenozoic Sedimentary Facies in Chalangla Area,Qiangtang Basin,Tibet

Oil gas formation and accumulation is related to sedimentary facies. Based on the field remote sensing date, the Mesozoic Cenozoic sedimentary condition in Chalangla area, Qiangtang Basin is studied for the evaluation of oil and gas potential. It is shown that there are two types of rock:clastic rock and carbonate rock;they are classified into 7 major facies (neritic facies, carbonate platform facies,littoral facies, delta facies, estuarine facies,fluvial facies and alluvial fan facies),18 subfacies and many microfacies. Marine continental transition facies is dominant in Upper Triassic sedimentary in wide range, and it is a regression cycle;neritic facies in Middle Jurassic is developed, marine continental transitional facies is main in Upper Jurassic; restricted carbonate platform is developed in Lower Cretaceous, and piedmont alluvial fan is developed in Upper Cretaceous.