| According to the development experience of home and abroad low-permeabilitysandstone reservoirs, low permeability reservoirs depend on the formation of naturalenergy can not provide enough capacity, so measures must be taken to increase production.Hydraulic fracturing is usually used to transform the method of formation. V42 block wasput into development in 1994. Each well has taken fracturing measures. During fracturingdesign, the basic single-well production is based on the case may be. As the single welldesigned to maximize productivity, it lacks of the overall concept in blocks. In thedevelopment process, the interaction between the fractured well becomes increasinglysignificant, so single-well fracturing design shortcomings are also shown. This paperstudies the design methods of improved fracturing, having the object of the overall block,and it designs the measures of fracture optimization design making blocks of capacitymaximize. Main results:1. Applied equivalent seepage mechanics theory, we set up well fracturing wells yieldprediction formula in a network of different ways, whereby you can optimize optimalfracture parameter in case of different water saturation in different situations, and writecorresponding computer program. Designing to optimize the overall fracturing finds aneasy way.2. It's studied theoretically various parameters impact on the productivity. Fractureparameters under study include: cracks in the length of the production wells, injectionwells crack length, conductivity, pressure production wells, injection wells and pressureanisotropy. On this basis, we study respectively the fracture parameters optimization in thedifferent circumstances of formation water saturation: Sw= 30%, Sw= 50% and Sw= 60%;3. We study the effect of fracturing measures in the V42 block, and establish areservoir simulation model of V42 block. It's used the current mainstream ECLIPSEcommercial simulation software for modeling work in order to ensure the accuracy andversatility. The model after the end of the project can still be used in other numericalsimulation programs, or directly used for oil field production performance evaluation,which the oil investment is effectively guaranteed.4. According to the generating simulation model, it calculates the geological reservesof the study area. The study area is reported that the geological reserve is 113 million tons. Based on this data, we adjust some parameters of the model calculation, and the finalgeological reserves is 1.135 million tons. Basically it is consistent with the reportedreserves, in line with the requirements of numerical simulation.5. On the basis of actual production history data of V42 block, we carry throughhistorical matching work, which makes the establishment of the simulation model canreflect the actual situation of the block V42. History matching is the longest and largeststage of the workload during reservoir simulation. This study fits in strict accordance withthe standards of history, after three months of intense calculations, and completesproduction history matching work of V42 block competently.6. Reservoir development effectiveness analysis. On the basis of history matching, weobtained distribution of remaining oil saturation and formation pressure distribution.Combined with the actual production process information, it analyzes the effects ofreservoir development and evaluation.7. Based on V42 block simulation models, Combined with results of the previoustheoretical research, the application results of a variety of measures on V42 blockfracturing are simulated. It's concluded that: crack half-length suited to V42 block's actualconditions is 75m. Fracture conductivity is 30μm2.cm.
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