The Wamsutter Tight Gas Reservoir - The Role of Stratigraphy and Sedimentology in a Tight Gas Field Study

Laura A. Banfield¹, Jon Vaitl², and William A. Hill^1
1BP America, Houston, TX
²Consultant, Wimberley, TX

The Wamsutter tight gas field in the Eastern Green River Basin, Wyoming, has been in development since the mid 1970s with over 2500 wells drilled. The regional stratigraphic project was developed to provide a chronostratigraphic framework within which well and reservoir production histories could be better interpreted. Chronostratigraphic surfaces were mapped throughout the field using well log and seismic datasets keyed to a set of 21 regional cross-sections. Depositional environments were interpreted using well logs calibrated to multiple conventional cores. Combining the chronostratigraphic surfaces and the depositional environments facilitated the creation of gross depositional environment maps for key intervals. The relationships observed between the gas and water production in different depositional environments can then be related to time equivalent deposits. This extrapolation provides a basis for the optimization of density and location of future infill drilling opportunities and an improved understanding of the variability associated with reservoir deliverability and water potential.

AAPG Search and Discovery Article #90092©2009 AAPG Rocky Mountain Section, July 9-11, 2008, Denver, Colorado