Study Of Reservoir Logging Evaluation On The2nd Section Of Feixianguan Formation Of YX Area In Northeast Sichuan

The YX structure of Northeast Sichuan is located in Bazhong block,whosetectonic deformation is weak and overall buried depth is relatively deep.In this area,due to types of marine carbonate reservoirs of second section of FeixianguanFormation,low porosity and permeability,serious heterogeneity and other factors,thereservoir logging responsing feature is partly influenced and it is difficult to identifygas-bearing situation in the reservoir.Therefore,based on the collection and analysisof typical drilling core materials and logging information, this paper mainlyestablishes logging interpreting models for reservoir parameters, selecting adequatefluid identification methods and thus forming a series of well logging technique usedin formation evaluation applicable to this study area.On the basis of systematic cognition of reservoir rock properties and physicalcharacteristics,this paper more precisely caculates mineral components,effectiveporosity and gas saturation,whose calculating errors exist in effective range and arein good agreement with practical standard.Meanwhile,fully utilize pre-existing testresults to analyse typical different logging responses of gas zone, water zone andgas-water mixed layer.By adopting porosity-saturation crossplot,normaldistribution,resisitivity logging and synthetical index methods to identify gas-bearingsituation in main reservoir from various aspects,and these results are basically accordwith that of practical production that attains the purpose of identification.Finally inconnection of reservoir parameters,the standard of lower limitation of reservoireffective thickness is comprehensively determined from several characteristics suchas lithology,physical property and the resistivity characteristic.Through this thesis study,it will provide effective referrence and techniquesupport for gas reserves and corresponding developmental techniques research in this area.