Controlling factors of fluid distribution in common sandstone reservoirsof Z Oilfield in Liaodong Bay

Studies of controlling factors of fluid distribution are important for oil-gas exploration. The Shahejie Formation reservoirs in Z Oilfield are typical conventional sandstone reservoirs in stratified structure with complex fluid distribution. The controlling factors in structure and sedimentation were analyzed to identify the fluid distribution with the data obtained in the study block. Results show that the types of vertical fluid distribution could be classified into continuous concentration and multistage dispersion, while the those of planar fluid distribution included continuous, dispersible, partitioned, and partially inverted types. The planar distribution of fluid in the study area is mainly controlled by the planar distribution and connectivity of sand bodies, ways of fault sealing and joining, and locally complicated structural configuration. The vertical fluid distribution was controlled by the interlayer between sand bodies. Due to sedimentary and tectonic factors, the differences of fluid distribution had been intensified, forming multiple fluid systems in the study block. This research shall have a strong significance of guiding efficient development in future.