Green River Basin
The Basin was formed during the Cretaceous period sourced by underlying Permian and Cretaceous deposits. The GRB is host to many anticlines created during the Laramide Orogeny trapping many of its hydrocarbon resources. It is bounded by the Rawlins Uplift, Uinta Mountains, Sevier overthrust belt, Sierra Madre Mountains, and the Wind River Mountain Range. The Greater Green River Basin is subdivided into four smaller basins the Green River Basin, Great Divide Basin, Washakie Basin, and Sand Wash Basin. Each of which possesses hydrocarbons that have been economically exploited.
Production in the GRB is dominated by natural gas and natural gas liquids (NGLs) from tight sands formations, primarily the Pinedale Anticline and the Jonah Field in Sublette County, and the Wamsutter Field in eastern Sweetwater County.
The Niobrara-DJ Basin is a crude oil and liquids rich gas play in Northeast Colorado and Southeast Wyoming. The Niobrara is in several areas of the Rocky Mountains, including Wyoming and in parts of Northwest Colorado. The portion that lies within the Denver-Julesburg (DJ) Basin is a combination shale/marl/chalk/sandstone formation that lies at depths 5,500′-8,500′, and is comprised of three separate zones, the A, B, and C benches. Just below the C bench sits the Codell tight sands formation, which is more of an emerging natural gas play, but is also garnering the interest of operators, especially those who are able to drill commingled Niobrara and Codell wells.
Located mostly in Southeastern Utah and Southwestern Colorado, the Paradox Basin has been known more for its conventional oil and gas production. Much of the petroleum production in the basin has come from porous carbonate deposits, such as algal mounds, of Pennsylvanian age. Additional reservoir types include uplifted fault blocks and discontinuous clastic beds with both stratigraphic and structural traps. The principal productive horizons in the basin include the Mississippian age Leadville Limestone, the Pennsylvanian Age Hermosa Group (Honaker Trail, Paradox, and Pinkerton Trail formations) and the Permian age Cutler Formation.
Powder River Basin
The Powder River Basin (PRB) in Northeast Wyoming and Southeast Montana, is well known for its coal production. The Basin also contains major deposits of petroleum, including the giant Salt Creek Oil Field. The oil and gas are produced from rocks ranging from Pennsylvanian to Tertiary, but most comes from sandstones in the thick section of Cretaceous rocks.
The Uinta Basin is a physiographic section of the larger Colorado Plateaus province, which in turn is part of the larger Intermontane Plateaus physiographic division. It is also a geologic structural basin in eastern Utah, east of the Wasatch Mountains and south of the Uinta Mountains. The Uinta Basin is fed by creeks and rivers flowing south from the Uinta Mountains. Many of the principal rivers (Strawberry River, Currant Creek, Rock Creek, Lake Fork River, and Uintah River) flow into the Duchesne River which feeds the Green River—a tributary of the Colorado River. The Uinta Mountains forms the northern border of the Uinta Basin.