ABSTRACT
Two hundred and seventy-seven exploratory wells were drilled in the Rocky Mountain region during 1948. Of these, 73 were successful. This represented a gain over the previous year, 1947, when, of 185 exploratory wells, 49 were successful. Permian and Pennsylvanian objectives provided the most new discoveries.
New pools discovered by the Sinclair-Wyoming Oil Company in the Deadwood formation of Cambrian age at Wertz and Lost Soldier, Sweetwater County, Wyoming, and by the Pure Oil Company in the Mesa Verde formation at West Poison Spider, Natrona County, Wyoming, were of great significance as neither of these formations had hitherto been productive in the Rocky Mountain states. Other important discoveries were in the basal Amsden at Big Wall and Melstone in central Montana and in the Hermosa formation at Dove Creek and Boundary Butte in the Four Corners area of Colorado and Utah. A deeper-pool discovery in the Weber formation at Ashley Valley, Uintah County, by the Equity Oil Company provided the source for the first commercial oil production in Utah.
Geophysical work increased during 1948, with the center of activity in Wyoming. Production of crude oil showed gains corresponding with the increased rate of exploratory drilling. Development drilling progressed rapidly particularly at Mush Creek, Weston County, Wyoming, where 88 new producers are reported. At Rangely, the development of the Weber Sand pool neared completion at the close of the year.
