Micropore structure and water driving characteristics of tight sandstone reservoirs in Ordos Basin

Abstract In order to explore the influence of micropore structure tight sandstone reservoir in water driving characteristics, studies on Chang 6 middle-western part Ordos Basin are carried out by various experiments such as cast-thin section analysis, scanning electron microscopy, high-pressure mercury injection and micro-water driving. The result shows that permeability contribution curves samples shift left sample decreases, indicating greater permeability, proportion large pores. is mostly dominated pores with radius larger than R 50 –R 60 . There big differences type, oil-driven efficiency residual oil distribution characteristics between reservoirs different types. type II major target subsequent exploration development, where types consist mesh finger, leaving mainly locked or isolated drops. size feature key factors dominating efficiency.