According to the Wyoming State Geological Survey, the Powder River Basin covers about 8,000 square miles and contains a sedimentary rock package that may locally exceed 40,000 feet in thickness. Sedimentary rocks range in age from Cambrian to Cretaceous.

In the 1970s, oil peaked at 160 million barrels per day. Current production is up about 12% since 2009, with more that 57.5 million barrels of oil produced in 2012.

Increased oil production is occurring primarily in Wyoming’s Campbell and Converse counties. In 2013, 204 horizontal oil wells were spudded and 522 other horizontal oil wells were granted permit-to-drill status in the two counties (an increase of 27% in Campbell County compared to 2012, and 40% in Converse County). Production from 504 Powder River Basin fields produced 48% of Wyoming’s total 2013 crude oil production.

Oil in the Powder River Basin is produced primarily from the Cretaceous age Frontier, the Shannon and Sussex sandstone members of the Cody Shale, and Mesaverde. The pre-Mississippian section is mainly of carbonate rocks and the Mississippian and younger rocks are mostly shale and sandstone.

This 23-page report contains geological descriptions, news, company activities, go-to reference links and more. It is included in your subscription.

Read the entire report here.