Triassic G Under The Group Of Sedimentary Facies Of The The Hongshanzui Oilfield

After referring to large numbers of correlative literatures, carefully watching and descripting bore cores, seriously studying spot data, and proceeding correlative lab analysis, through monolayer oil sand body subdividing and contrast, lithofacies dividing, log facies dividing etc, we summarized out sedimentary facies microfacies style and characteristics of KeXia formation of Middle Triassic series in HongShanZui oil field in conclusion as far as region of interest KeXia formation farther rolling exploration development offer own proposal.Through monolayer oil sandbody subdividing and contrast, we divided KeXia formation into two sand layer formations of S6 and S7, eight sand layers, and further step we subdivided into fourteen sedimentation units.The top boundary of KeXia formation was mudstone layer. The bottom boundary of KeXia formation was a plane of unconformity. The bottom boundary of S6 was watercourse erosion surface. All these boundaries were regional maker layers.Through analysis of lithofacies, log facies analysis, we considered that KeXia formation was pluvial fan facies and braided river facies amphi-phase state sediments. Underpart S75 layer was pluvial fan facies sediment, and further step subdivided into five kinds of microfacies styles: the braided flows the primary channel in the middle of the fan the braided flows the shallow channel in the middle of the fan the braided shifting sand dam the braided shape channel in the verge of the fan the braided shape channel sand dam in the verge of the fan .Six sand layer formations of upper part S₇⁴-S₆¹ layer were braided river facies sediment, further step subdivided into four kinds of microfacies: the main course of braided river the shallow course of braided river sand dam flood plain.The studied region sediment is highly asymmetrical longitudinal in possession of succession, in individually nature date, sedimentary system distribution and initiation water system are general identity, basically for SWW—NEE, from west to east have got four stable braided river courses.