3D Geological Modeling Of The Member 2 Of Shahejie Formation Of Da 65 Block In Dawangbei Oilfield

Da 65 block in Dawangbei oilfield is located in the Da 65 nose structural belt in the middle of Chezhen sag,the structure of Da 65 fault block is complicated.In recent years,although some work has been carried out,the research is not systemic and thorough enough,espicially,The correlation of the thin layers is not fine enough,The sedimentary feature,sand distribution are not clear enough,Correct 3D geological models have not been established.Based on the above problems,fine isochronal stratigraphic division and correlation of thin layers is carried out in this study.Initial fault model is established by using the fault data of seismic interpretation,Combined with the logging fault-point datas,initial the fault model is corrected.Finally,fine structural framework model is established.After this,the microfacies,sand distribution are studied deeply,the sedimentary facies model is established by using deterministic modeling methods,attribute models which are controlled by sedimentary facies are established by using stochastic simulation methods,which provides a reliable geological basis for further study of remaining oil and flood pattern modification.Five research results of this study are as follows:(1)Fine isochronous stratigraphic framework is established.Based on the stable development marker layer of mudstone and gypsum formation,the member 2 of Shahejie formation is divided into 7 sand sets and 38 thin layers by sedimentary cycle comparison methods,the key sand sets are further divided into 27 subdivision layers.(2)The structural characteristics of da 65 block are clarified,and the accurate structure model is established,the fault model is corrected in many ways by synthetically using the fault stick datas provided by seismic interpretation and the fault-point datas provided by logging interpretation,Finally,accurate fault model is established.Thus,the strike,dip,dip angle and intersected relation between the faults are clear.(3)The sedimentary microfacies and the distribution of sand bodies are revealed,the Sedimentary microfacies model is established by using determinstics modeling methods.identifying signs of sediment facies from core observation,Lacustrine facies containing four sedimentary microfacies types of the spatial distribution and connectivity of various sand bodies in the study area are determined.(4)According to well logging interpretation parmeter values,different layers are simulated with different spatial structure parameters,Under the control of sedimentary microfacies,the attribute model is set up by using stochastic simulation algorithm.(5)Fine 3D geological model of Da 65 block is set up,the structural framework model,sedimentary microfacies model and reservoir property models are basically consistent with the reservoir real situation,these models have has high reliability.