
The Bighorn Basin in Wyoming
The 'Bighorn Basin' is a
plateau region and
intermontane basin, approximately 100 miles (160 km) wide, in north-central
Wyoming in the
United States. It is bounded by the
Absaroka Range on the west, the
Bighorn Mountains on the east, and the
Owl Creek Mountains and
Bridger Mountains on the south. It is drained to the north by tributaries of the
Bighorn River, which enters the basin from the south, through a gap between the Owl Creek and Bridger Mountains, as the
Wind River, and becomes the Bighorn as it enters the basin. The region is semi-arid, receiving only 6-10 in (15-25 cm) of rain annually.
The basin was explored by
John Colter in 1807. It was later transversed by the
Bridger Trail, which was blazed in 1864 by
Jim Bridger to connect the
Oregon Trail to the south with
Montana. The route was important alternative to the
Bozeman Trail, which had crossed the
Powder River Country, but had been closed to white settlers following
Red Cloud's War.
The largest cities in the basin include the Wyoming towns of
Thermopolis,
Worland, and
Powell.
Sugar beets are grown on irrigated farms in the region.
Geology
The Bighorn Basin forms a geologic
structural basin filled with more than 20,000 feet of sedimentary rocks from
Cambrian to
Miocene in age. Since the early 20th century the basin has been a significant source of petroleum, and has produced more than 1.4 billion barrels of oil. The principal souce of oil is the
Pennsylvanian Tensleep Formation; Other important petroleum horizons are the
Mississippian Madison Limestone and the
Cretaceous Frontier Sandstone.
[1] Some
uranium has been mined in the northern part of the basin, along the
Bighorn Mountains (see ''
Uranium mining in Wyoming'').
Communities
Notable Features
★
Heart Mountain
★
Red Gulch Dinosaur Tracksite
★
Bighorn Canyon National Recreation Area
References
1. John P. Weldon (1972) ''The Big Horn Basin'' in ''Geologic Atlas of the Rocky Mountain Region'', Denver: Rocky Mountain Association of Geologists, p.270-272.