A prominent natural landmark for emigrants on the Oregon Trail, Scotts Bluff, Mitchell Pass and the adjacent prairie lands are set aside as the 3,000 acre Scotts Bluff National Monument. This site preserves the memory of the historic Oregon, California and Mormon Trails. The monument museum contains exhibits about the human and natural history of the area and also holds a unique collection of watercolor paintings by the frontier photographer and artist William Henry Jackson. Scotts Bluff National Monument was established in 1919 by Presidential Proclamation primarily for its historical significance and unique geological features. While human history is the dominant theme today at Scotts Bluff, the area’s natural history provides the setting in which a multitude of significant human events has transpired. Its principal natural value is the topographically diverse landscape in which the main features of the historic landscape are still preserved.
Scotts Bluff National Monument lies within the western Great Plains in an area that was once almost continuous mixed and short grass prairie and that is now largely utilized for farming and ranching. The Monument lands encompass two large, cliff-rimmed, bluffs: Scotts Bluff and South Bluff. Most of the land within the boundary is in native mixed-grass prairie with some previously disturbed areas harboring a variety of non-native vegetation. There is also an area of mostly barren badlands between the north base of Scotts Bluff and the North Platte River.
The landscape at the beginning of the Oregon-California Trail time period was primarily “natural” and largely “undisturbed,” in a pre-European habitation sense. Euro-American emigrants arriving during the mid-nineteenth century found a landscape here that was richer in wildlife and more sparsely wooded than it is today, but the essential features of the scene the imposing bluffs rising from the plains are relatively unchanged. The effects these emigrants had on the landscape were certainly significant, but the landscape that evolved was still primarily “natural,” overlain with periodic and concentrated human disturbance. The expansive plains, prominent bluffs and the dominant prairie vegetation made up the primary elements of the landscape. The plains and bluffs suffered immediate, but relatively little long term, disturbance from the passing of the emigrants. The vegetation near the trail was probably heavily affected by the concentration of both human traffic and large numbers of livestock. The vegetation probably regenerated in a short time due to the extensive root systems of the native plants, because of nearby seed sources available on the surrounding undisturbed lands and because natural ecosystem processes remained intact.
The region’s landscape and that of Scotts Bluff National Monument are very different than they were 150 years ago. The plains and bluffs remain, but now are dotted with buildings, roads, trails, canals and trees. A large portion of the prairie vegetation has been disturbed, now resembling a “patch work” pattern of multiple disturbance events of various levels of intensity, size and recovery. A significant portion of the lands surrounding the Monument have been converted to farmland or residential areas; therefore, nearby native seed sources are scarce. Many of the natural processes that helped shape the landscape, such as grazing by bison and other native fauna and naturally ignited fires, are now gone or severely limited. Climatic influences and erosion still take place, but in some places the natural erosion rate may be accelerated by human-caused impacts.
Nature & Science
The Scotts Bluff National Monument’s Presidential Proclamation states that Scotts Bluff has “scientific interest… from a geologic standpoint.” The scientific interest of this site has been apparent since the late 1890′s when the U. S. Geological Survey made the first formal geologic investigation of the area. Geologic publications relating to Scotts Bluff number at least nine and the area continues to be the subject of investigation. Although it appears the geology of Scotts Bluff has been well studied, the statement in the proclamation helps focus on one of the primary natural resources of the Monument, its geology. Scotts Bluff is a topographic feature rising to 4,649 feet above sea level and 800 feet above the North Platte River. The geology of Scotts Bluff is significant from a natural resource standpoint because it affords a view of 740 feet of continuous geologic strata that spans a time period extending from 33 to 22 million years before present. This north face of Scotts Bluff has exposed the most geologic history of any location in the state of Nebraska. Visitors can easily view this resource while walking the Saddle Rock Trail.
Scotts Bluff, like the adjoining Wildcat Hills and nearby Chimney Rock, Courthouse and Jail Rock, has been and continues to be weathered out of geologic deposits of alluvial origin that made up the ancient high plains of the region prior to regional uplifting. Approximately 5 million years ago the rate of erosion increased in this region as the Rocky Mountains to the west were uplifted. Wind and stream deposits of sand and mud, wind deposits of volcanic ash and supersaturated groundwater rich in lime formed the layers of sandstone, siltstone, volcanic ash and limestone that now comprise Scotts Bluff’s steep elevation, ridges and the broad alluvial fans at its base. The high plains that were formed at that time were gradually eroded away, except at certain locations that were protected by a caprock of hard limestone that was more resistant to erosion. This caprock covers the tops of the bluffs in the area, slowing their rate of erosion relative to the unprotected surrounding (and eroded) countryside. This process resulted in the area’s unique geologic features, such as Scotts Bluff. Erosion is usually unseen by humans, as wind, rain and snow slowly wash away grains and particles of sand, silt and ash. However, erosion can occur as sudden, large rock falls like what happened in 1974 and 2000. A badlands formation is located between the north base Scotts Bluff and the North Platte River, where deeply incised arroyos support little or no vegetation.
The exposed rocks of Scotts Bluff are Tertiary in age and are non-marine in origin. They belong to several stratigraphic units the Arikaree Group, which contains the Monroe Creek – Harrison and Gering Formations and the White River Group, which contains the Whitney and Orella Members. The Monroe Creek – Harrison Formation is the “top” of Scotts Bluff and overlays the Gering Foundation. It dates to 22 million years before present. It is unknown what deposits were laid down above this formation. The Monroe Creek – Harrison Formation is pale brown and light gray, silty and very fine to fine-grained sandstones. The caprock of the Monroe Creek – Harrison Formation and therefore Scotts Bluff is calcite-cemented “pipy” concretions of limestone. The concretions maintain a consistent northeast-southwest orientation over much of the Nebraska Panhandle. Evidence indicates that the concretions formed shortly after the deposition of the host sand. The sandstones of the Monroe Creek – Harrison Formation contain 25 – 50 percent silic glass shards and an additional 25 to 40 percent crystal and lithic pyroclastic detritus. The lower layers of this formation also contain invertebrate burrows. Insects, possibly beetles, may have dug them. They may have been shelter burrows, deposit-feeding burrows, or vertical passages.
The Gering Formation consists of thin, horizontally stratified pale brown to gray brown, very fine to fine-grained, volcaniclastic sandstone. One inch in diameter “sand crystals” developed in several layers. The discoidal shape of these sand crystals indicate that they were formed by the growth of gypsum, which has since been replaced by calcite. The Gering Formation also contains a number of ash beds. In the vicinity of the foot tunnel on the Saddle Rock Trail concave-up deformation structures are common. They are thought to be tracks of vertebrates. The scale and bilobed nature of some structures indicate that some of the track-makers were large ungulates probably entelodonts. Other potential track-makers that lived at this time included a variety of oreodonts, hyracodontid rhinos, tapirs, small horses, camels and a variety of carnivores.
Below the foot tunnel approximately 40 feet begins the Whiney Member of the Brule Formation and White River Group. The White River Group contains 40 to 70 percent silic glass shards and an additional 20 to 30 percent crystal lithic pyroclastic detritus. The mineralogy, grain size, texture and regional mantling nature of the Whitney Member suggest that it represents a slow accumulation of airfall pyroclastic material. The pyroclastic material was derived from western-source rhyolitic and volcanic centers. The probable sources being in Colorado. The Whitney Member is a massive, pinkish-brown, volcaniclastic siltstone with two vitric ash beds.
The oldest exposed rocks (33 million years before present) are of the Orella Member of the Brule Formation and White River Group. This is the badlands area of the Monument and consists of siltstones and mudstones with interbedded thin lenticular sandstones. These included a wide variety of sedimentary structures, diagenetic features, trace fossils and volcaniclastic sediments.
The geology of Scotts Bluff is also significant for historical reasons. Emigrants typically traveled within the Platte River Valley on both sides of the river; however, at Scotts Bluff the geology of the badlands forced the emigrants out of the valley. The badlands presented a barrier to travel because they stretched from the base of the bluff to the river itself. Once the emigrants moved out of the valley, the bluff formations forced the travelers to look for a pass to allow them to move through the bluffs and continue on their westward journey. The two closest passages were at Robidoux Pass and Mitchell Pass. Those traveling by wagon used Robidoux Pass in the early years because the pass at Scotts Bluff was not fit for wagons.
Recreation
The Oregon Trail Museum contains three rooms of historic, geological and William Henry Jackson exhibits. The Summit Road allows visitors to drive to the top of Scotts Bluff for a spectacular view of the valley.
The 1.6 mile Saddle Rock Trail leads hikers from the visitor center to the summit and the 0.5 mile Oregon Trail Pathway leads from the visitor center to the remnants of the Oregon Trail.
Getting There
By Plane
Commercial flights in and out of Western Nebraska Regional Airport at Scottsbluff.
By Car
Visitors traveling on Interstate 80 can exit at Kimball, Nebraska and drive 45 miles north on Highway 71. Follow National Park Service signs 2 miles west of Gering, Nebraska, on State Highway 92. Visitors following the old Oregon Trail along the North Platte River using State Highways 26 or 92, should follow National Park Service signs.
Getting Around
Personal vehicles can be driven to the summit; or, a free shuttle service to the summit is offered during the summer.
Traveler Facts
Contact Information
Scotts Bluff National Monument
P. O. Box 27
Gering, NE 69341-0027- or -
Scotts Bluff National Monument
190276 Highway 92 West
Gering, NE 69341-0027
Phone: 308-436-4340 (Headquarters)
Fax: 308-436-7611
Operating Hours & Seasons
Scotts Bluff National Monument is open daily from 8:00 a.m. – 5:00 p.m.; Daily From Memorial Day to Labor Day, the monument is open from 8:00 a.m. to 7:00 a.m. The monument is closed December 25 and January 1.
Weather / Climate
Generally sunny, hot and dry in the summer. In late summer the weather is extremely variable with occasional afternoon thunderstorms. Windy and cold in winter. Wear comfortable clothing appropriate to season. Hats are useful against exposure to sun. Good walking shoes are recommended for use on hiking trails.
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