Shale-gas well productivity estimates in USGS assessments from 1995 to present are based on studies that require decline curve fits and analysis to a large sample or to all wells within a particular assessment unit. Probabilistic type curves can be created on nearly any size well group and were designed for use within a resource context. The probabilistic type curve was designed to improve on the familiar format of a deterministic type curve by showing the full range of production possibilities for a given group of wells. Additional information was added to make certain components, such as data density and nonproducing wells, more explicit.

First posted July 21, 2010