Research And Application Analysis Of Volume Calculation Method For Shale Gas Stimulation Production

Shale gas reservoirs are typically characterized by very low permeabilities, and thus, the pressure depletion from a producing well may not propagate far from the well during the life of a development. Currently, two approaches are widely utilized to perform unconventional reservoir analysis:analytical techniques, including the decline curve analysis and the pressure/rate transient analysis, and numerical simulation. The numerical simulation can rigorously account for complex well geometry and reservoir heterogeneity but also is time consuming.In this thesis, we propose and apply an efficient technique, fast marching method (FMM), to analyze the shale gas reservoirs.Our proposed approach stands midway between analytic techniques and numerical simulation.In contrast to analytical techniques, it takes into account complex well geometry and reservoir heterogeneity, and it is less time consuming compared to numerical simulation. The fast marching method can efficiently provide us with the solution of the pressure front propagation equation, which can be expressed as an Eikonal equation. Our approach is based on the generalization of the concept of depth of investigation. Its application to unconventional reservoirs can provide the understanding necessary to describe and optimize the interaction between complex multi-stage fractured wells, reservoir heterogeneity, drainage volumes, pressure depletion, and well rates. The proposed method allows rapid approximation of reservoir simulation results without resorting to detailed flow simulation, and also provides the time-evolution of the well drainage volume for visualization.Based on the diffusive equation and Fast Marching Method, we build the calculation model of stimulated reservoir volume. For shale gas reservoirs, the reservoir compaction caused by pressure depletion is quite important. Accounting for the compaction effect, we run the calculation model of stimulated reservoir volume with synthetic horizontal well with three stage fractures. And we also predict the pressure response and flow rate combining Geometric Approximation.