Study On Fine Division Of Sedimentary Units And Remaining Oil Tapping In Block P108

Block P108 now has entered the development of high water-cut period.However,there are problems such as low sand channel drilling rate,low level of water flooding control,difficulties in selecting wells and selecting layers,as well as the poor results.Therefore,it is urgent to carry out research on the fine anatomy and tapping potential of single sand bodies,and to form the supporting technologies for reservoir descriptions and fine-tuning with a single sand body as the basic adjustment unit,and finally the economic and effective measures were adopted to increase the ultimate recovery rate to a greater extent.In this paper,the fine division of reservoir sedimentary units is firstly performed on the block,then the potential of a single well is quantified and a potential digging chart is developed.The research is based on seismic data,core data,dynamic data and logging data,and it is based on well logging geology,sedimentary petrology,petroleum geology,modern reservoir geology and geostatistics as the theoretical basis.First,geological modeling and numerical simulation are carried out to quantify the remaining oil potential.According to the sedimentary characteristics of the P108 block,the identification standards and classification principles of single sand bodies are formulated,and the identification and division of single sand bodies are carried out on 26 small layers in the study area,and six types of single sand bodies are identified,including the compound channel,the interlaced channel,the distributary channel,the single channel,the mat like sand body and the lens sand body.Then,combining the analytic theory and method of Maill and Professor Ma Shizhong’s hierarchy structure,using the five level interface principle,the typical single sand body of the study area is divided into the internal hierarchy and the structure description according to the size of the gradation interface.The concept of heterogeneity index is introduced to quantitatively characterize the heterogeneity of reservoirs in the study area.On this basis,the static and dynamic data and numerical simulation results are combined,the remaining oil in the single sand body in the study area was divided into five types according to the genesis,namely,well pattern imperfection,plane interference,mud wedge(fault)shielding,sand body edge,thick oil layer,and the introduction of a single well.In addition,the concept of single well potential coefficient was introduced to quantitatively characterize the potential of a single well,and a single sand body residual oil exploration model was developed using oil and water wells as a unit,and the old oil field production was guided scientifically and efficiently.The oil and water wells are used as the units to formulate the potential submarine maps for the remaining sand bodies,and to scientifically and efficiently guide the production of the old oil fields.