Frontier Formation of the Southwest Powder River Basin
- Study Text and Figures
- 11 Outcrops Measured
- 51 Cores Described
- 962 Study Wells
- 100 Thinsections Examined
- 5 Field Studies
- 26 Regional and 8 Field Maps
- 6 Cross Sections
This study of the Frontier Formation of the Southwestern Powder River Basin examines the stratigraphy, sedimentology, petrography, and oil and gas potential of the region. The Frontier Formation has been divided into three members, the Belle Fourche, Emigrant Gap, and Wall Creek. Detailed analysis of wells, measured sections, and cores establish a chronostratigraphic framework that is essential for explorationists in this complex play.
The Frontier play consists of three principal reservoir sandstone types including shoreface, transgressive lags, and reworked shelf sand bodies, including prodelta "plumes." The origins and distributions of these sandstone types are portrayed within the context of the complicated transgressive-regressive history of the Frontier.
The study area covers more than 6400 square miles, within which 962 wells were analyzed and represents more than four man-years of geologic research.