New and improved technology is required to enhance gas production from low permeability reservoirs of the Western United States. These reservoirs constitute a major target for new and supplemental supplies of natural gas. Their development depends upon demonstrating sufficient gas in place and productivity to justify economically the drilling, fracturing and operation of wells. These reservoir rocks are characterized by lenses of low permeability sand of limited, variable lateral extent and thickness enclosed in a matrix of shale and silty shale. If favorable reservoir conditions can be found in the sand lenses, the problem may become one of intersecting a sufficient number of the gasbearing lenses with an induced fracture to ensure economic production.