The Study Of Sedimentary Characteristics And Reservoir Heterogeneity Of The1^st Member Of Qingshankou Formation In The Hei96-123Block, Daqingzijing Oilfield

Hei96-123block is located in the southeastern part of the three-dimensionalwork area of Daqingzijing oilfield, and is lying in the eastern slope of DaqingzijingOilfield syncline in construction. It belongs to the complex lithology of low porosityand extremely low permeability reservoir block. With the conduct of the waterflooddevelopment, the reservoir block has revealed a number of problems, such as the lossof reserves, the main reservoir flooded prominent, the contradiction between layers,and the unclear understanding of reservoir sands. In order to solve the many issues ofthe of the study area is facing, this thesis is mainly done the research of thesedimentary characteristics and reservoir heterogeneities. It will lay the geologicalbasis for later oil field of implementation of CO2flooding overall developmentprogram.Identifying the core and log interface firstly, combining with the previoushierarchical data, the original layers are subdivided in single sand body, and meantimecorresponding them to the ultra-short-term cycles, at last the28monosandbody rankultra-short-term cycles were divided comprehensively. After mastery of the regionalgeological background information, combing with the color value of mudstone, clasticmaturity and heavy mineral data, the provenance of the study area is determined andis from the southwest direction. During the1stmember of Qingshankou formation, thelake is in the expansion, and under the water-transgression condition the research areadeveloped the destructive delta sand body. On the basis of observation and descriptionof the block inside and nearby core, combined with logging data comprehensiveanalysis, found that the study area mainly developed delta front. The delta front issubdivided into river mouth bar, front sandbar, offshore bar, sand sheet, bay betweensand bar or sheet microfacies types. Then according to the characteristics of distribution of sand and microfacies, the destructive delta depositional model isestablished, and the maps of4sand group of sedimentary evolution are drawn. It ishelp to understand the sedimentary characteristics and evolutionary law of thatperiods. At last, choosing the typical core data and logging data, processing themstandardizedly, this will make the logging data truly reflect the information of stratum.And then establishing the reservoir properties on the basis of standardized logs (GRand AC), calculating the study area of porosity and permeability. The data of porosityand permeability were processed and analyzed by applying the statistics principle, thereservoir heterogeneity of research area is evaluated by selecting valid parameters, thereflected plane anisotropy of porosity and permeability distribution are drawn, and theinfluence of the microfacies types to the reservoir heterogeneity is analyzed.Comprehensive analysis indicates that the reservoir heterogeneity of1st member ofQingshankou formation is strong in Hei96-123block.This thesis is based on sequence stratigraphy, sedimentary petrology, petroleumgeology theory. After fully digesting and absorbing the results of previous studies, theoriginal layers are subdivided in monosandbody rank. Combining with the core,logging, analysis of laboratory data, the sedimentary microfacies characteristics andevolutionary laws of the study area are researched, the reservoir macroscopicheterogeneity is analyzed detailedly according to the logging data. These researchesprovide a reliable geological basis for the later implementation of CO2floodingoverall development.