The Water Injection Feasibility Research On Chang2Low

Zhiluo oilfield is a typical extra-low permeable oilfield, and Chang2are main oil bearing series in Late Triassic. According to its drilling, logging and experimental analysis data, and through these experimental methods such as the X-ray diffraction, physical property test, scanning electron microscope, intrusive mercury experiment etc, the paper analyzes sedimentary facies, lithology, pores structure, diagenesis, physical property of Chang2reservoirs. By the analysis of production method,development formation division,development well grid and well spacing,single well daily rate and recovery efficiency prediction, etc, a development plan was brought to effect for development in the area.Studies suggest that:Chang21oil bearing beds are the major oil producing formations in the study area. The study area of Chang2is situated in Yan’an delta. Micro-facies are mainly occurred in the submerge distributary channel and distributary interchannel and a stable channel development. Moreover, its sandbodies are fundamentally together. Chang2reservoirs is mainly fine arkose feldspar sandstone. Compositional Maturity is low but textural maturity is high. Grain size sorting is better and the grain shape is mostly subangnlar. We draw the conclusion that the reservoir space of the Chang2oil bearing is dominated by intergranular pore, secondary dissolution pore and main microthroat. Pore throat type is mainly medium pore-micro throat. Dominant diagenesis types are compaction, cementation, replacement and dissolution. Through reservoir engineering analysis, using a layer systemand a well developed network is more reasonable. Results of numerical simulation show that anti—nine square well pattern, the wells’s distance in180—210m.