Abstract: Reinterpreting the Pinedale Anticline in the Green River Basin: Implications for Future Hydrocarbon Exploration

Joseph P. Fagan Jr.

The Green River Basin is a northwest-southeast elongate structural feature located in southwestern Wyoming. Bounded by three basement uplifts, this complex mountain front basin possesses tremendous gas reserves. Production has been limited to a few structures, such as the Pinedale Anticline, because of the great depth of the basin.

The Pinedale Anticline is an elongate structure that parallels the front of the Wind River Thrust. Earlier research has suggested that the anticline is not related to basement, but rather is associated with a foreland detachment structure.

A new, high-resolution aeromagnetic survey has been modelled in detail and the results indicate that the Pinedale Anticline may actually be a basement related structure. Profile modelling normal to the anticline from the LaBarge Platform to the Wind River Mountains suggests that not only is Pinedale Field situated on a possible basement structure, but also that additional, heretofore unknown analogous features are also present in the basin.

Additionally, an east-northeast structural grain is prevalent throughout the aeromagnetic dataset. This trend has been correlated with structures exposed in the Wind River Mountains and has also been shown to be important to locating hydrocarbon production. Thus, Cretaceous and Paleocene reactivation of Proterozoic age faults may have significantly affected location of structures, local stratigraphy and, subsequently, emplacement of hydrocarbons.

AAPG Search and Discovery Article #90952©1996 AAPG Rocky Mountain Section Meeting, Billings, Montana