Found an old paper of John P Lockridge from 1976 on the Niobrara and Goshen. The man was looking forward. GLTA
Abstract: Cretaceous Frontier Sandstone, Southeastern Wyoming and Western Nebraska
John P. Lockridge
Significant oil and gas fields are present from Alberta, Canada, to New Mexico in Cretaceous Frontier and equivalent age sandstones along the eastern margin of several western-derived coarse clastic wedges. The easternmost progradation of Frontier sandstone extended into the southeastern Wyoming and western Nebraska part of the northern Denver basin, and sandstones were deposited which are equivalent to the first Frontier (or first Wall Creek) of the Casper arch and southwestern Powder River basin areas.
Three areas of sand deposition can be delineated in the northern Denver basin. A deltaic complex extends across the present Hartville uplift from the southern Powder River basin into eastern Platte and west-central Goshen Counties, Wyoming, and includes a maximum of 100 ft (30 m) of sandstone.