The Green River Formation is an Eocene geologic formation that records the sedimentation in a group of intermountain lakes in three basins along the present-day Green River in Colorado, Wyoming, and Utah. The sediments are deposited in very fine layers, a dark layer during the growing season and a light-hue inorganic layer in the dry season. Each pair of layers is called a varve and represents one year. The sediments of the Green River Formation present a continuous record of six million years. The mean thickness of a varve here is 0.18 mm, with a minimum thickness of 0.014 mm and maximum of 9.8 mm.
The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Most were deposited in warm, shallow seas and near ancient, long-gone sea shores in western North America. Both marine and terrestrial sediments are represented, including lithified sand dunes from an extinct desert. There are at least 14 known unconformities in the geologic record found in the Grand Canyon.
The geology of the Grand Teton area consists of some of the oldest rocks and one of the youngest mountain ranges in North America. The Teton Range, partly located in Grand Teton National Park, started to grow some 9 million years ago. An older feature, Jackson Hole, is a basin that sits aside the range.
The exposed geology of the Capitol Reef area presents a record of mostly Mesozoic-aged sedimentation in an area of North America in and around Capitol Reef National Park, on the Colorado Plateau in southeastern Utah.
Fossil Butte National Monument is a United States National Monument managed by the National Park Service, located 15 miles (24 km) west of Kemmerer, Wyoming, United States. It centers on an assemblage of Eocene Epoch animal and plant fossils associated with Fossil Lake—the smallest lake of the three great lakes which were then present in what are now Wyoming, Utah, and Colorado. The other two lakes were Lake Gosiute and Lake Uinta. Fossil Butte National Monument was established as a national monument on October 23, 1972.
The Beartooth Mountains are located in south central Montana and northwest Wyoming, U.S. and are part of the 944,000 acres (382,000 ha) Absaroka-Beartooth Wilderness, within Custer, Gallatin and Shoshone National Forests. The Beartooths are the location of Granite Peak, which at 12,807 feet (3,904 m) is the highest point in the state of Montana. The mountains are just northeast of Yellowstone National Park and are part of the Greater Yellowstone Ecosystem. The mountains are traversed by road via the Beartooth Highway with the highest elevation at Beartooth Pass 10,947 ft (3,337 m)). The name of the mountain range has been attributed by the U.S. Forest Service to a rugged peak found in the range, Beartooth Peak, that has the appearance of a bear's tooth. Originally, the Beartooth Mountains were named after Beartooth Butte, a large block of paleozoic sediments on the Beartooth Plateau, and Beartooth Butte was named for a tooth-like structure that projects from the front of the butte.
Protaspididae is an extinct family of pteraspidid heterostracan agnathans. Fossils of the various genera are found in early Devonian-aged marine strata. Protaspidids were once thought to represent a transitional form between the Pteraspididae and the Psammosteida, bearing the broad head shield shape of the latter, due to a more benthic (bottom-dwelling) existence, but recent phylogenical comparisons demonstrate that the protaspidids are actually highly derived pteraspidids, and that the anchipteraspidids, the most primitive of pteraspidids, are the sister-group of the psammosteids.
Dorfopterus is a genus of eurypterid, a group of extinct aquatic arthropods. Only one fossil of the single and type species, D. angusticollis, has been discovered in deposits of the Early Devonian period in the Beartooth Butte Formation in Wyoming, in the United States. The first half of the name of the genus honors the discoverer of this formation, Erling Dorf, while the second half consists in the Ancient Greek word πτερόν (pteron), meaning "wing". The species name angusticollis is composed by the Latin words angustus ("narrow") and collum ("neck").
Specimen Ridge, el. 8,379 feet (2,554 m) is an approximately 8.5-mile (13.7 km) ridge along the south rim of the Lamar Valley in Yellowstone National Park. The ridge separates the Lamar Valley from Mirror Plateau. The ridge is oriented northwest to southeast from the Tower Junction area to Amethyst Mountain. The ridge is known for its abundance of amethyst, opal and petrified wood. It was referred to as Specimen Mountain by local miners and was probably named by prospectors well before 1870. The south side of the ridge is traversed by the 18.8-mile (30.3 km) Specimen Ridge Trail between Tower Junction and Soda Butte Creek. The trail passes through the Petrified Forest and over the summit of Amethyst Mountain el. 9,614 feet (2,930 m).
Afairiguana avius is an extinct iguanid lizard known from a nearly complete and articulated skeleton discovered in rocks of the Early Eocene-aged Green River Formation of Wyoming, United States. As of the initial description, the skeleton represents the oldest complete iguanian from the Western Hemisphere, and is the oldest representative of the extant iguanid family of anoles, Polychrotidae.
The Supai Group is a slope-forming section of red bed deposits found in the Colorado Plateau. The group was laid down during the Pennsylvanian to Lower Permian. Cliff-forming interbeds of sandstone are noticeable throughout the group. The Supai Group is especially exposed throughout the Grand Canyon in northwest Arizona, as well as local regions of southwest Utah, such as the Virgin River valley region. It occurs in Arizona at Chino Point, Sycamore Canyon, and famously at Sedona as parts of Oak Creek Canyon. In the Sedona region, it is overlain by the Hermit Formation, and the colorful Schnebly Hill Formation.
Amethyst Mountain, el. 9,609 feet (2,929 m) is the highest peak and central part of a northwest – southeast trending ridge that lies between the Lamar River to the northeast and Deep Creek to the southwest within Park County, Wyoming. From northwest to southeast, this ridge consists of Specimen Ridge, Amethyst Mountain, and the Mirror Plateau in Yellowstone National Park. The nearest town is Silver Gate, Montana, which is 19.2 miles away.
The Wasatch Formation (Tw) is an extensive highly fossiliferous geologic formation stretching across several basins in Idaho, Montana, Wyoming, Utah and western Colorado. It preserves fossils dating back to the Early Eocene period. The formation defines the Wasatchian or Lostcabinian, a period of time used within the NALMA classification, but the formation ranges in age from the Clarkforkian to Bridgerian.
The Chalk Butte Formation is a geologic formation in Oregon, which forms a part of the Idaho Group. It preserves fossils dating back to the Neogene period. It was proposed along with the Grassy Mountain Basalt Formation and the Kern Basin Formation as a division of the Idaho Group rocks in the Mitchell Butte Quadrangle. The predominant rock types are tuffaceous sandstones, siltstones, and conglomerates with smaller amounts of tuff, ash beds, and freshwater limestone. A partial section at the type location determined the formation to be about 538 feet thick.
The Coyote Butte Limestone (OR085) is a geologic formation in Oregon. It preserves fossils dating back to the Sakmarian to Kungurian stages of the Permian period, spanning an estimated 23 million years. The formation occurs in isolated buttes to the north; Triangulation Hill, and south; type locality and name giver Coyote Butte and Tuckers Butte, on either side of the Grindstone and Twelvemile Creeks in Crook County, Oregon.
Anarthraspis is an extinct genus of arthrodire placoderm fishes which lived during the Early Devonian period. It contains two species described in 1932, Anarthraspis chamberlini and Anarthraspis montanus, both found in the Beartooth Butte Formation of Wyoming and Montana, USA, and assigned to the genus in 1934.
Murmur is a genus of placoderm. The type species is Murmur arctatum. It was described from a fossil found within the Beartooth Butte Formation of Wyoming.
The geology of Wyoming includes some of the oldest Archean rocks in North America, overlain by thick marine and terrestrial sediments formed during the Paleozoic, Mesozoic and Cenozoic, including oil, gas and coal deposits. Throughout its geologic history, Wyoming has been uplifted several times during the formation of the Rocky Mountains, which produced complicated faulting that traps hydrocarbons.
Beartooth Butte is in the Beartooth Mountains in the U.S. state of Wyoming. The peak is located in the Absaroka–Beartooth Wilderness of Shoshone National Forest. Rising more than 1,500 feet (460 m) to the northwest above Beartooth Lake, the butte is easily seen from the Beartooth Highway. Unlike the granitic rocks that comprise the vast majority of rocks to be found in the Beartooth Mountains, Beartooth Butte consists mostly of sedimentary rocks. It has the most easily accessible rocks of the Beartooth Butte Formation a geologic formation that preserves fossils dating back to the Devonian period.
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