Research On Fine Dissection And Differences Of Water Injection Effcet

Xingshugang oilfield is located in north of the daqing placanticline structure, Xingbei development area is located in the northern Xingshugang structure, has entered the late development of high water. In this paper, the research object is western of Xing5 district, the central of Xingbei development area, carried out main factors of the effect in large composite sand body.PI3 unit belongs to delta distributary plain facies, distributed by large area of distributary channel sand body, with positive rhythm and composite positive rhythm. For the statistical analysis of PI32, PI3₃², determine the PI3₃^2can be divided. According to the superimposition of thick composite channel sand body and the lower layer sand, sedimentary characteristics of bottom lag deposited,based on the background of reservoir sedimentation, combined with the cause analysis of the sand body, and the shape recognition of the fine log curve, the sand body in the study area variation types into 8 types. The high precision reservoir fine description technology as the foundation, comprehensive utilization of well logging and geological data,with the recognition of single sand body, the original basis of PI3₃² layer is divided into PI3₃^2a,PI3₃^2b, PI3₃^2c three sedimentary units. According to the "sandstone, multiple layers, channel sand body, relatively concentrated, obviously cycle" feature, ultimately determined the standard well is X4-D4-312. Guided by fine fluvial sedimentology, established diverse and comprehensive single well logging curve model. Draw each time unit of sedimentary microfacies map, channel microfacies well developed in the plane of PI32, PI3₃^2a, PI3₃^2band has lots of other categories. PI3₃^2c doesn’t have channel microfacies, mainly develop overbank sand microfacies. Based on core property data and aspiration profile data, using the theory of interpretation model analysis, carried out comparative study between on-site interpretation models and new logging interpretation model. Chosen the GR and RMG curve as logging algorithm factor which can clearly distinguish the poor bottom of sand body, established the second log interpretation model, using second well logging interpretation model to reinterpretation and re-cognition for physical property data.From the plane, inner layer, layer three aspects to carry on the study of reservoir heterogeneity, target zone has thick sandstone,more interlayer, moderate or better physical properties. Overall, the reservoir heterogeneity is weak, but permeability ratio of non-water absorption of PI3₃^2b is bigger, heterogeneity is stronger. The interlayer of study area mostly contiguous distribution extremely developed in the plane, largely distribution area and mostly distribution in the channel microfacies. The microfacies of distributary channel have a large number of sand layer, and large number and thickness of the interlayer. From main river channel-river pattern 1-river pattern 2-river pattern 3-other pattern of river-other microfacies, the total number of interlayer and the number of interlayer in individual sand body has decreased, frequency and density ofinterlayer has increased, caused the heterogeneity enhanced. Comprehensive utilization of plane of distribution in sedimentary facies, storage coefficient, flow coefficient, Putaohua formation divided into five types of flow units. PI32, PI3₃^2a, and the upper PI3₃^2b belong to A,B, C class flow unit, the lower PI3₃^2b and PI3₃^2c belong to D, E class flow unit, poor physical property. The study area has basic well pattern, first infill well pattern, second infill well pattern, polymer flooding pattern. The influence of basic well pattern on the research area is the biggest. The northern part of the study area near water wells of the basic well pattern. This is a key factor about the differences of water injection between north and south.By reinterpreted of physical logging, fine-grained sedimentary unit and compared,anatomy of single sand body, heterogeneity study, flow units and different batches well flooding and other law analysis. Carry out a comprehensive analysis on the different effect of the bottom, summarized the reasons for the variation of the physical property at the bottom.The main reason for the difference in the water injection efficiency of the large complex channel sand is pointed out the sand body with the change of the bottom of the sand body is not continuous. This causes the heterogeneity strongly. On these basis, to improve understanding of the development law of the study area, and guide significance for similar area measures of tapping the potential of the work.