Using well performance as the primary determining factor, a systematic study and evaluation was conducted on numerous vertical and horizontal wells drilled in the high-pressure/high temperature heterogeneous carbonate reservoirs to assess effectiveness of stimulation treatments and benefits of using novel technologies. Numerous variables analyzed to determine impact on production include well type, wellbore length, drilling azimuth, number of stimulation stages per well, chemistry and volumes of treatment fluids, pumping rates and pressures, fracture dimensions (half-length and width), and applied drawdown. A comprehensive database for stimulated wells was created that included reservoir parameters, completion data, minifrac and main stimulation treatment parameters (fluid types, volumes, rates and pressures), computed fracture geometry, and normalized well performance data. The variables were grouped and arranged according to their similarities and impact on well productivity. Correlations were drawn using the Pearson correlation coefficient to compute upward and downward data trend, ensure use of good quality data, and discard few nonaligned data. Numerous, very useful plots are constructed and presented that show the different trends of the variables evaluated and how they affect the productivity index (PI) of a well.

Results have been drawn based on completion parameters, design and execution variables, treatment evaluation results, and well production. The results demonstrate the importance of real-time application of geomechanics to achieve borehole stability and drilling laterals toward the minimum in-situ stress σmin) direction to achieve sustained post-treatment gas rates. Trends also highlight improved well performance with the increase in stimulation stage count and maintaining isolation between producing intervals. The influence of different fluid types and their volume on post-fracturing productivity was analyzed. Normalized PI was used to assess optimum pump rates and pressures. Some important conclusions were made regarding targeted etched fracture half-length and width. The analyses identified the key post-fracturing production drivers in the gas reservoirs and their impact on long-term well performance.

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