A variety of completion and stimulation practices have been used in Eastern Devonian Shale wells during the more than 60 years since its initial development. Over 1000 wells in thirty-four counties located in the west central part of the Appalachian basin, were analyzed to investigate the effects of these practices on well productivity. This study represents the largest investigation to date of post-treatment response using a reliable indicator of the well's long-term deliverability for comparing both explosive and hydraulic fracturing methods.

The traditional measure of well productivity, initial open flow, gives a poor indication of the well's long-term potential. The cause of this poor relationship can be partially attributed to the insufficient test times run during open flow measurements. A more representative indicator of long-term potential, available early in the well's life, has been identified.

Based on location data from wells in the study area, field development of the Devonian shale has been associated with existing localized fold/fault systems. Drilling activity appears to concentrate around structures created as a result of major basement tectonic activity.

The purpose of this study was to isolate the effects of stimulation practices from the background effects of geology and differential reservoir depletion rates. By recognizing these sources of variability, comparison of well productivity for the various stimulation practices was made using standard statistical inference techniques.

The results of this study indicate that larger stimulation treatments, either by explosive shooting or hydraulic fracturing, have not generated incremental improvements in well productivity on a regular basis. A group of post-1975 wells were analyzed to limit the time dependant effects of reservoir depletion. Results from this group indicated natural completions, at a statistically significant level, exhibited greater productivity as compared to that of nitrogen fractured or shot wells. In evaluating the more modern practice of hydraulic fracturing, the foam fractured wells exhibited significantly greater productivity than comparable wells stimulated by explosive shooting.

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