Study On The Evaluation Of Fluid Advantage Channels In Glutenite Reservoir

The paper took glutenite reservoir of Lower Karamay formation from the 7-middle district in Xinjiang Oilfield as study target and focused on the dominant channel between wells formed by long-term water injection.Methods,such as comprehensive Production dynamic,Rdos,numerical simulation were applied to locate the distribution of liquid dominant channels in various stages.Besides,an analysis on the factors relevant to the generation of these dominant channels and a summary of their impacts on the oilfield exploration were conducted,which provide references to the future exploration and innovation of the Xinjiang Oilfield.Methods of Production dynamic response,Liquid production and water uptake test,Pressure drop curve,Polymer production curve,grey relational analysis,Rank correlation,resistance coefficient between wells,Rdos and ECLIPSE numerical simulation were used to distinguish the dominant channels of wells,and combined with parameters of Reservoir physical property,Sedimentary microfacies,surface and vertical heterogeneity to proof and analyze the accuracy.Twenty I-level,twenty-fourⅡ-level and twenty-fourⅢ-level d channels were found during the\initial Water flooding development phase,and compared with the tracer test results,they have high matches,with 93%in the tracer test resultand 89%in the dynamic response.Besides,combined with the characteristics of the development of the reservoir physical properties,the development direction and the vertical distribution of the dominant channels,a study on the parameters of reservoir features prone to form dominant channels and favorable sedimentary facies was conducted.Vertically,dominant channels are prone to form at the layers of S₇³-1-1 and S₇³-2-2 which have better physical properties,while on the surface,they are likely to develop at the north of the district,especially at the corner well.As far as the physical properties,dominant channel are prone to develop in the vertically heterogeneous braided river facies with sound physical property and in the injection and production well group with sound extension,undertheconditionsofpermeability>50,porosity>16%,abrupt injection coefficient>1.2,Variation coefficient>0.3,Differential>4.A conclusion can be made combined with a comprehensive analysis on the distinguishing results of the dominant channel and characteristics of glutenite reservoir that long-term injection changed the original grain framework,pore-throat-net and clay mineral to form dominant channel,and the intensive well pattern distribution and high-intensity exploitation escalate its forming speed.Finally,relevant suggestions for the future exploration are provided at the end of this paper.