Production Prediction Method Study For Fractured Gas Well In Xushen 6 Block

In the proven gas reservoir, the low permeability formation and extra low permeability formation account for a large part. For the reservoir with low permeability, the production of a single gas well is very low, and the majority of gas reservoir has no natural production without being fractured. Therefore, the hydraulic fracturing technique is often adopted for the improvement of low peability gas reservoir. A big vocanical gas reservoir was discovered in the Xujiaweizi area of Daqing Oilfield in 2002, but the production prediction model for fractured homogeneous gas reservoir is still used today in the aspect of production prediction for the fractured complex lithologic reservoir, which lacks pertinence and is quite different from th real condition. Also, the main affecting fractors of fractured gas well production can't be analyzed accurately, whcich made the fracture optimization of gas well lack of scientific basis. According to the problem above-mentioned, the main work done in the thesis is as follows:Firstly, the basic characteristics of volcanical reservoir are investigated in the Xushen Gas Field, the flow patterns of fractured gas well in the triple porosity volcanical reservoir and glutenite reservoir are analyzed, the production prediction model of fractured gas well are developed for volcanical reservoir and glutenite reservoir, and the basic principle of production prediction is given for fractured gas well.Secondly, by meas of Laplace Transformation and Duhamel Principle, the analytical production solutions relative to time are obtained for the fractured gas wells in volcanical reservoir and glutenite reservoir, the double log curves of production decline are drawn, the production decline law is dicussed for the fractured gas reservoir, and the affecting rules of the formation and fracture parameters on the production are abalyzed for the fractured gas wells.Thirdly, the theoretical curves of fracture half-length and flow conductivity are drawn, the parameter optimization curves are obtained under different conditions, the fracture half-length and flow conductivity are optimized and analyzed, the optimizing method is given, the influence of fracture half-length and flow conductivity on the stimulation effect are analyzed through the optimization curves, finally the fracturing desigh for actual gas well is optimized.Finally, combined with the geological logging and fracturing data for the development of Xushen 6 Block, the parameter determination method is obtained for the production prediction of fractured gas wells in Xushen 6 Block, the production prediction method is established, which is suitable for the fractured gas well of Xushen 6 Block, and the production prediction method is validated by using actual field case.