Geophysical data were fundamental in the economic development of the Pinedale field. Early exploration in Pinedale was prompted by the presence of a large thrust-faulted anticline, which could be better mapped with the use of both potential field geophysical data and seismic data. Because Pinedale is a complex field having attributes of both a stratigraphic trap and a structural trap, understanding the complexity of the accumulation involved extensive application of 3D seismic data. Microseismic and crosswell seismic data were utilized to provide details about the orientation and lateral extent of sand bodies and the behavior of hydraulic fractures used to stimulate the wells for enhanced productivity. Further, seismic data and analysis supplied information critical to the definition of the field limits both vertically and horizontally. This understanding of the field limits has evolved over time with increased well control and calibration to the currently defined field area to indicate a current reserve potential of 58.7 tcf of original gas in-place (OGIP) and 38.2 tcf of recoverable gas.