The Research On Hydrocarbon Enrichment Regularity Of Chang6Reservoir In Tianciwan Area

This essay has studied the stratum Chang6of Tirassic Yan’chang Formation inTianciwan，Ordos basin. By using cyclic sedimentation theory and foundation knowledge ofElectrical measuirng curve, Chang6stratum can be divided into four reservoir segmentsie:Chang64、Chang63、Chang62> Chang6i. By analyzing types of sedimentary fades andcharacteirstics of Microfacies according to the basic knowledge of logging trace andprecipitation facie signs，we can make sure that Chang6stratum develops delta plainsubfacies. For that development of sand body is controlled by sedimentary facies and sandbody in distributary channel occupies most space of reservoir bed，its distribution directionis rfom North-east to South-west.By studying reservoir petrology、characteirstic of physical property> hole structure ect,we have done some researches on characteirstics of Chang6and finally got an conclusion:the main type of rock is feldspar-porphyry sandstone, psephicity is times pirsmatic andsorting rate is high as well as maturity of deposit structure.The main hole types are thinhole-thin bottleneck and thin hole-tiny thin bottleneck. Low permeability layer and ultra lowpermeability layer stands most part of Chang6stratum.Chang6stratum is controlled largelyby sedimentary facies and diagenic metamorphism.For this region of reservoir having suiffcient oil sources、good diagenetic condition、highquality capping formation ect，we can conclude that hydrocarbon source rocks whichdevelops in Chang7stratum of southern part of studied region provides sufifcient mateiral forChang6reservoir; Sand body in distirbution channel is a important palace for stoirng oil andgas; nosing structure controls the distirbution of oil and gas; On the basis enrichment patternstudies of oil and gas，we can predict the beneficial exploration region of Chang6stratum andprovide geology references for the future exploration at last.