Evaluation Of Water Injection Development Effect In Low Permeability And Thin Interbed Reservoir

The low permeability and thin interbed reservoir is the main type of low permeabilityreservoirs in Shengli oilfield, which has specific geologic characteristics, such as multi-layerin vertical, the thin monolayer and wildly spread oil blocks. And the reservoir with badphysical property, low natural deliverability and the conventional development difficulty isusually developed by Large scale fracturing in vertical wells or fracturing in horizontal wells.Meanwhile, the pressure of this reservoir should be kept timely, generally, through the waterflooding to get the ideally development effect and high recovery interiorly. Evaluating thewater injection development effect in low permeability and thin interbed reservoirscientifically is of great importance to improve the water injection development effect andexplore the potential reserves. Referring to the evaluation methods and principles of waterinjection in different reservoirs, especially in low permeability reservoir, considering thecurrent research of the study areas, with the methods of oil engineering, numerical simulation,fuzzy mathematics, hierarchy analysis and the principle of membership function, this papersystematically confirmed the ideas and principles about the evaluation of water injectiondevelopment effect and the selected method of the indices, according to the results ofprevious studies. Secondly, two aspects including water injection development potential andthe effect of water flooding were evaluated in light of actual needs and the indices systems oftwo aspects were improved innovatively. The membership function was introduced toimprove the mathematical basis of the previous research. Evaluation criteria and calculatingmethod for each index were selected and verified. Then, based on the block of differentdevelopment models, the well pattern and fracture parameters about the development of theimitation of horizontal wells and fracturing horizontal well were researched by the method of numerical simulation and production dynamic prediction were researched on block accordingto the optimal parameters. Finally, based on the actually statistical data and the results ofnumerical simulation, the water injection development effects were comprehensivelyevaluated on research areas. The evaluation results of water injection development potentialof target block1and target block2are the better and the better close to the best, andthe evaluation results of the water injection development effect are the best, which play animportant role in the water injection development of the oilfield in the future.