Bighorn Mountains
The Bighorn Mountains are a mountain range in northern Wyoming in the United States, forming a northwest-trending spur from the Rocky Mountains extending approximately 200 miles (320 km) northward on the Great Plains. They are separated from the Absaroka Range, which lie on the main branch of the Rockies in western Wyoming, by the Bighorn Basin.
The range is the location of the headwaters of the Little Bighorn, Tongue, and Powder rivers.
The highest peaks of the range include Cloud Peak (13,167 ft) and Black Tooth Mountain (13,005 ft).
The highest peaks within the Bighorns are within Bighorn National Forest. Bighorn Canyon National Recreation Area consists of approximately 120,000 acres within the Bighorn Mountains.
The Bighorn Mountains were uplifted during the Laramide orogeny beginning approximately 70 million years ago. The Bighorn Mountains consist of over 9,000 feet of sedimentary rock strata laid down before mountain-building began: the predominantly marine and near-shore sedimentary layers range from the Cambrian through the Lower Cretaceous, and are often rich in fossils. There is an unconformity where Silurian strata were exposed to erosion and are missing. Following the uplift, large volumes of sediments, rich in early Tertiary paleontological resources, were deposited in the adjoining basins.
External link
- Paleontological resources doc. format