Numerical Simulation of Oil Displacement in Complex Fault Block Reservoir

In China, complex fault blocks occupied an important position in the development of oilfields. Compared with monolithic sandstone reservoirs, complex fault blocks have the characteristics of complex and diverse structures and relatively developed low-level fault blocks. Such special oil reservoirs often have an impact on the development of the injection-production well pattern. Therefore, it is necessary to study its influence and optimize related deployment. According to the parameters of the selected example blocks, an ideal reservoir model is established and four well pattern distribution forms are designed. According to the simulation results, we will choose the best oil displacement pattern. Under the same physical and well pattern distribution conditions, the injected water or CO2 was simulated and the simulation results were compared. Finally, the influence of the fault length on the oil displacement effect on the two-dimensional plane of the entire reservoir was studied. The results show that under the condition of high injection-production pressure difference, well pattern 1 has the best water drive development effect. Comparing the oil saturation distribution cloud map of water flooding and gas flooding and the oil production rate curve of producing wells, CO2 is significantly better than water flooding in terms of oil displacement speed and production. After changing the length of the fault, it was found that due to the influence of the openness of the fault, as the length of the fault increases, the overall oil saturation distribution of the reservoir is greatly different. The initial oil production increases rapidly, but cumulative oil production changes. It is not obvious. Research reveals that the transfer of fault length affects the formation pressure and then changes the injection-production pressure difference and ultimately affects the initial oil production.