Research on Zhong I area Yan 10 reservoir classification and residual oil distribution law in Maling oilfield

Zhong I area Yan 10 reservoir in Maling oilfield is located in the south west of Yishan slope tectonic unit of Ordos basin.After 30 years progressive exploration and development,it has entered rapid decreasing period.Residual oil distributed scattered and complex.Based on the existing geological data and the real situation of low permeable oilfield,four parameters as substrata avarage thickness,porosity,permeability and oil saturation have been selected to evaluate the reservoir classification of Yan 10 reservoir,the study reservoir is divided into one,two and three kinds.According to Zhong I area production well dynamic data analysis,combined with the change of stratum pressure during the oilfield development,the residual oil distribution is determined,the distribution characteristics of the residual oil is summarized,which provided important basis for residual oil exploitation in oil field later development.