Geography and geology of a portion of southwestern Wyoming with special reference to coal and oil

Reconnaissance for uranium-bearing carbonaceous rocks in northwestern Colorado, southwestern Wyoming, and adjacent parts of Utah and Idaho

“…However, tuffaceous beds in the vicinity of Sage are similar to the Browns Park and White River formations and probably once unconformably overlapped all of the coal-bearing rocks at Sage. These tuffaceous beds were mapped by Veatch (1907) as the Fowkes formation but their nature and distribution suggest that they are not part of the Fowkes formation as it was defined.…”

“…The coal occurs chiefly in the Bear River formation of Lower Cretaceous age and the Frontier and Adaville formations of Upper Cretaceous age in a belt of complexly folded and faulted rocks. The coal has been described by Veatch (1907) and Schultz 'a" indicates equivalent uranium content of less than 0. 001 percent The presence of silicic volcanic rocks overlapping the coal-bearing formations in this area (Mansfield, 1920, andRoss andForrester, 1947) made it seem a likely area for reconnaissance prospecting.…”

Correlation chart of lower Cretaceous rocks, Madison Range to Lima Peaks area, southwestern Montana

“…The stratigraphy of the Upper Cretaceous Frontier Formation and correlative strata has not been worked out in the western part of southwestern Montana; hence, facies relationships between the Frontier and Upper Cretaceous rocks of the Colorado Group in northwestern Montana are unknown. The Aspen Formation (Veatch, 1907) is geographically restricted to eastern Idaho and western Wyoming, where it is used in conjunction with the underlying Bear River Formation. Strata described here resemble the Blackleaf Formation in northwestern Montana more than they resemble the Bear River Formation.…”

Molluscan fauna of the Morrison formation, with a summary of the stratigraphy

“…In southwestern Wyoming and the adjacent parts of Utah and Idaho the name Morrison has not been used, but an equivalent of the Morrison formation was most probably included locally in the Beckwith formation (Veatch, 1907). Where the Beckwith has been divided (Mansfield, 1927), as in central western Wyoming and adjacent parts of Idaho, the Ephraim conglomerate, basal formation of the Gannett group, must contain any equivalent of the Morrison formation present, for it is underlain by the marine Jurassic Stump formation (equivalent to the Curtis formation faunally) and is overlain by the Peterson limestone, which contains a Lower Cretaceous nonmarine fauna.…”