Combination of Array Dielectric Measurements and Nuclear Magnetic Resonance Data for Better Fluid Identification in the Urho Tight Conglomerate Oil Reservoir, Junggar Basin

Abstract The Upper Urho Sandy Conglomerate Reservoir in Xinjiang oilfield features complex lithology, low porosity and low permeability, and a majority of secondary pores with poor connectivity. Due to those characteristics, the log responses are complicated and it is difficult to determine the oil saturation with conventional resistivity method. In this paper, the reservoir heterogeneity was studied based on image logs and nuclear magnetic data, and oil saturation was calculated using array dielectric data. An integrated reservoir evaluation and fluid identification approach was established and applied in five wells located in different fault blocks. The testing results from four of them have proved the effectiveness of the proposed method. This is the first time to use array dielectric tool to identify fluid type in conglomerate reservoir with volcanic matters, and it has been introduced to similar oil reservoirs in other oilfields, which also obtained good application effect.