中国克拉通盆地构造—沉积分异及其对规模性碳酸盐岩储集体发育的控制作用OA

The marine cratons in China are characterized by"small scale,poor tectonic stability,and strong tectonic-sedimentary differentiation."Through the basin prototype restoration and paleogeographic evolution studies of the Tarim Basin,Sichuan Basin,and Ordos Basin,this study classified the types of tectonic-sedimentary differentia-tion.Through the typical dissection of three types of large-scale reservoirs—the reef-shoal facies of the Sinian Dengying Formation in the Sichuan Basin,the intra-platform grain shoals of the Cambrian Longwangmiao Formation and Xixiangchi Group,and the Ordovician paleokarst in the Tarim Basin—the controlling mechanisms of tectonic-sedimentary differentiation on the development of large-scale reservoirs were summarized.The results indicated that:(1)during the extensional-convergent tectonic cycles of marine basins,the orderly superposition of rift basins,passive continental margin basins,cratonic depression basins,and foreland basins controlled the systematic development of reef-shoal facies,intra-platform grain shoal facies,and paleokarst reservoirs.(2)In strong extensional periods,intra-cratonic and marginal rifts controlled the development of reef-shoal reservoirs.In weak extensional-weak compressional periods,intra-cratonic depressions governed the formation of intra-platform grain shoal reservoirs.In strong compressional periods,the formation of paleo-uplifts controlled the development of karst reservoirs.(3)The development of high-quality reservoirs in platform-margin reef-shoals and intra-platform grain shoals was generally controlled by high-energy facies zones,early dolomitization,and early dissolution.Under strong tectonic differentiation,high-quality reservoirs exhibited zonal distribution,whereas under weak differentia-tion,they showed discontinuous planar distribution.(4)The development of karst reservoirs was controlled by parent rock lithology,paleoclimate,tectonic geomorphology,and exposure duration.Under tectonic differentiation,karst reservoirs showed planar or zonal distribution.In marine cratonic basins,tectonic-sedimentary differentia-tion not only controlled the types of carbonate reservoirs but also shaped their developmental models and distribu-tion patterns.