A Study on Reasonable Injection-Production Network in Tahe Oil field Fractured Reservoir

The models of fractured carbonate rock reservoirs are much different from other reservoirs. And there is not a mature method of study of well density today. We studied schemes formulaic-well fracture-cavern units of carbonate reservoirs through numerical simulation. They are including the optimal injection–production well network, timing of water injection, the relative vertical locations of injection and producing intervals as well as the types of reservoirs. For fracture-cavern reservoirs, water injection should begin at a pressure maintenance level about 90% to prevent the pressure of the reservoir from slowing down the decline rate caused by the energy decline and from restraining the bottom water coning. The optimal injection–production well network should be based on network rules well according to geological situation. The injection wells should be placed at a low position, while the production wells should be placed at high position to improve the effect of water injection development effect owing to the gravity difference function of oil and water.