Oil(water) Layer Identification In Chang-6 Reservoir Group In C Area Of Ordosbasin

With poor reservoir properties,strong heterogeneity,complicated pore structure,and strong diagenetic,the Chang-6 reservoir group in C area of Ordos Basin is a typical low-porosity and low-permeability sandstone reservoir.Duo to these characteristics,the electrical response in well logging is not obvious and oil(water)layer is difficult to identify.In view of the problems existing in identification of oil(water)layers in the Chang 6 reservoirs in this area,this paper studied the characteristics of reservoir petrology,formation water,and microscopic pore structures,basic geology,well logging,core test analysis and testing data and comprehensively evaluated the reservoir from microscopic.On this basis,the critical borehole throat radius,reservoir physical properties,and oil-bearing limits were determined.At the same time,the “four natures” analysis of the reservoir,the important logging parameters,and the lower electrical limit were determined.The analysis and establishment of plate in Class I,II and Class III and Class III and oil(water)layers was identified in the Chang 6 reservoirs,and verify the accuracy of the reservoirs in combination with test data.This will provide a theoretical basis for further oil and gas exploration and development in the region.