EXCO-North Coast's has conducted pilot tests to add incremental reserves in a thin Marcellus through a contrarian approach toward stimulating that shale. In these underpressured Jackson County, West Virginia shale wells, slickwater fracture stimulations were used instead of the more common nitrogen gas or nitrogen foam fluids. The premise for this departure from the standard nitrogen gas or foam treatment was that water, being non-compressible, drives net pressure better in shale stimulations, improving chances of opening other planes of weakness or natural fractures with high pump rates and fluid volumes. Further, there was a sense that the Marcellus shale may not be as sensitive to fresh water as previously thought, at least not in the sense that there are swelling or migrating clays to detrimentally impact production. There still may be concerns about relative permeability effects of water on the shale, water imbibition by the shale, and short and long-term liquids management. Recovering as much stimulation water as fast as possible without damaging the induced fracture's conductivity and keeping the shale perforations dry should be best for gas production. Two wells were drilled to the Marcellus shale. Uphole zones commonly stimulated in a multi-zone same day completion were skipped to allow for a Marcellus only production test. The Reciprocal Productivity Index was used to gauge stimulation effectiveness in one of the wells.

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