Investigation of post-acid stimulation impacts on well performance using fracture modeling and reservoir simulation in a Jurassic carbonate reservoir

Well stimulation (well fracturing) became an essential tool in the Oil and Gas industry to unlock the potential of unconventional reservoirs all over the world and especially in the Middle East. In Kuwait, well stimulation is obligatory when dealing with deep Jurassic carbonate reservoirs. Thus, the well fracture designing process plays a very critical role in determining the success of the stimulation job and the improvement of the recovery. Several wells stimulated with 20% HCL have shown wide variations in both short and long term well production performance. The research aims to investigate and identify the possible reasons causing these variations by creating an integrated workflow comprised of two modeling sections using actual field data. Fracture Modeling; to assess the fracturing operation and obtain the fracture geometry and conductivity using StimPlan software. Reservoir Simulation; to test the fracture design by the performance of the well using Petrel and Eclipse software. The iterative process in the workflow also gives the ability to tailor the design to reach the maximum potential of the well. Three major reasons are suspected to be behind the underperformance of the investigated well. First, human errors in planning and gathering the required data for the stimulation job. Second, the stress contrast between the layers allows the fracture to propagate vertically giving more fracture height than length. Third, the fracture orientation, which has a great effect on the long-term performance by allowing the induced fracture to intersect with the formation and the natural fractures --Abstract, page iii