· Abstract

· Acknowledgments

· Introduction—Video of Exploration and Production Through Time

· Units of Measure

· Undiscovered Oil and Gas Resources in the Southwestern Wyoming Province

· Undiscovered Gas in the Mesaverde Total Petroleum System

· The Almond Continuous Gas Assessment Unit

· The Rock Springs–Ericson Gas Assessment Unit

· Undiscovered Gas in the Mesaverde–Lance–Fort Union Composite Total Petroleum System

· The Mesaverde–Lance–Fort Union Continuous Gas Assessment Unit

· Undiscovered Gas in the Lewis Total Petroleum System

· The Lewis Continuous Gas Assessment Unit

· Undiscovered Gas in the Hilliard-Baxter-Mancos Total Petroleum System

· The Hilliard-Baxter-Mancos Continuous Gas Assessment Unit

· Undiscovered Gas in the Mowry Composite Total Petroleum System

· The Mowry Continuous Gas Assessment Unit

· Undiscovered Gas in the Lance–Fort Union Composite Total Petroleum System

· The Lance–Fort Union Continuous Gas Assessment Unit

· Reservoirs That Contain the Majority of Undiscovered Gas Resources

· Live Data and Maps

· In Summary

· References Cited

Undiscovered Gas in the Mesaverde Total Petroleum System

The Mesaverde TPS contains the largest amount of estimated undiscovered natural gas (mean of 25.8 TCFG) in the Southwestern Wyoming Province and produces hydrocarbons from sandstone and coal reservoirs in the Upper Cretaceous Mesaverde Group (Johnson and others, 2005). The Mesaverde TPS encompasses about 11,500 mi² of the eastern part of the Southwestern Wyoming Province where the Lewis Shale is present (Johnson and others, 2005). The Lewis Shale, which overlies the Mesaverde Group and pinches out west of the Rock Springs uplift, as shown in the following cross-section, forms a regional seal separating the Mesaverde TPS from the overlying Lewis TPS. West of the pinch-out, there is no regional seal separating the Mesaverde TPS from overlying continental rocks of Late Cretaceous and Paleocene age, and the Mesaverde Group is combined with the overlying Upper Cretaceous Lance and Paleocene Fort Union Formations to form the Mesaverde–Lance–Fort Union Composite TPS (Johnson and others, 2005).