PETERSON, JAMES A.
Department of Geology, Univ. of Montana, Missoula, MT 59812

Abstract: Carboniferous-Permian (Late Paleozoic) Hydrocarbon System, Rocky Mountains-Great Basin U.S. Region

Carboniferous-Permian rocks form an important closely-related regional hydrocarbon source-reservoir System covering several basins of the Rocky Mountain-Great Basin region. The System includes oil & gas accumulations in the Williston basin and Sweetgrass Arch areas of North Dakota and Montana; the Bighorn, Wind River, and Powder River basins of Wyoming; the Uinta, Sand Wash, and Piceance basins of NE Utah and NW Colorado; the Paradox basin of the Four Corners area; and the basins of east-central Nevada. Additional major resources within this stratigraphically-related system are the central Utah partly-eroded tar and heavy oil deposits in Permian & Lower Triassic sand reservoirs, including the Tar Sand Triangle, arguably the largest original in-place accumulation in the United States.

Regional & local detailed palinspastic studies, including stratigraphic, sedimentary facies, paleotectonic, organic-rich potential source rock & reservoir facies distribution, and burial depth-fluid migration history, assist in recognizing processes related to origin of these extensive oil and gas accumulations.

The estimated volume of total original hydrocarbons generated & accumulated in these Late Paleozoic rocks elevates this System to a highest rank in the Rocky Mountains U. S. region.

AAPG Search and Discovery Article #90928©1999 AAPG Annual Convention, San Antonio, Texas