Study On The Depositional Microfacies Of The Third To Fourth Member Of Quantou Formation In Donglei Block Of Xinmin Oilfield

The target of this dissertation is to investigate the depositional microfacies and genetic sand and remaining oil distribution of Fuyang reservoir in third to fourth member of Quantou formation in Donglei block of Xinmin oilfield, Jilin oil region of South Songliao basin, under the guide of theory of high-resolution sequence stratigraphy fluvial sedimentary and fine modern reservoir description in dense well network area.Using reservoir correlation methods such as the cycling isochronal correlation controlled by facies and standard layers, correlation among lacustrine flooding surfaces or fluvial flooding surfaces to divide the initial 16 layers of the reservoir into 34 sedimentary units and create their logging facies model. And then using the discrete well microfaices restricted by sediment system and spatial facies model to carry on comprehensive research on the plane microfacies ,and describe the features of single sand body in one time unit in order to describe it accurately as high as genetic single sand boy in vertical, microfaices unit in horizontal.The result of research shows the various kinds of river channel is effective reservoir, including distributary channel, small size crevasse channel, and minor channe,then predict the distribution of 180 single-sand bodies. And after analyzing the heterogeneity of sand body, point the minor channels, especially, have important influence on the intraformational oil-flooding direction, forming and distribution of remaining oil because of their function as barrier, breaking fluid and poor permeability in fluvial sand body.Based on the core description, and analysis of cross section and plane microfacies, we discover the combination genesis and internal infrastructures of the large size of compound sand bodies and classify them into four groups and eight subgroups in terms of their of their vertical superimposed or cut types. This kind of sand body is characterized by widely spread, good connectivity, and high property and oil saturation, consists of the main oil layers.The Fuyang reservoir is sourced from Southwest, belong to shallow delta system controlled by river, including five sedimentary models and creating the vertical evolution sequence.Together with produce data in injection-production well network, we do research on distribution of remaining oil, and find six kinds of remaining oil distribution, and predict the distribution of remaining oil, in every single sand body. As a result, we provide supports and evidences for regulation of injection-production wells and measures for developing oil potential.The research result is applied by oil industry and achieves good effect,Which contribute to the producing in Xinmin oilfield.