Abstract

Mississippian rocks are truncated in a northeast direction across the map-area. The erosional limits of the various formations are shown.

The Bakken is thickest in the east part and thins northward and westward, where only the lower black shale unit is recognizable.

The Banff thins eastward and changes from a basinal facies in the Foothills to a shelf facies in the Plains. The Banff formation of the type section is not the Banff formation of the Plains. In order to be consistent with established Plains usage, it is proposed that the Banff formation and the Rundle group at the type section be re-defined.

The Elkton member of the Turner Valley is the most important oil and gas reservoir in the area. Accumulation occurs at the erosional up-dip edge of the Elkton, in stratigraphic traps controlled by facies changes, chanelling, and by the overlying impermeable Mesozoic shales.

Total recoverable reserves from the Turner Valley is 306,364,000 barrels of oil, — 88 percent of the total reserves of all producing zones in the area.