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Brule Formation
The Brule Formation was deposited between 33 and 30 million years ago, roughly the Rupelian age (Oligocene). It occurs as a subunit of the White River Formation in Nebraska, Colorado, North Dakota, South Dakota, and Wyoming. It is a sequence of fine grained clastic rocks (claystones, mudstones, siltstones) interbedded with freshwater carbonates, volcanic ash (tuff), and sandstone. Historical description The formation was named by N. H. Darton "for the Brule Indians, who once roamed over Pine Rldge Ind. Res. in southern S. Dak., where the fm. covers large areas, and that it is not present in Brule Ind. Res., which occurs farther NE In S. Dak." Darton's first description stated, "The White River beds In their extension from S. Dak. Into Nebr. present some differences in strat. range and relations. They expand considerably and include, at top, beds which appear not to be represented in the typical regions. Accordingly, to afford distinct definitions for the members in Nebr. I have I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Badlands National Park
Badlands National Park ( lkt, Makȟóšiča) is an American national park located in southwestern South Dakota. The park protects of sharply eroded buttes and pinnacles, along with the largest undisturbed mixed grass prairie in the United States. The National Park Service manages the park, with the South Unit being co-managed with the Oglala Lakota tribe. The Badlands Wilderness protects of the park's North Unit as a designated wilderness area, and is one site where the black-footed ferret, one of the most endangered mammals in the world, was reintroduced to the wild. The South Unit, or Stronghold District, includes sites of 1890s Ghost Dances, a former United States Air Force bomb and gunnery range, and Red Shirt Table, the park's highest point at . Authorized as Badlands National Monument on March 4, 1929, it was not established until January 25, 1939. Badlands was redesignated a national park on November 10, 1978. Under the Mission 66 plan, the Ben Reifel Visitor Center ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyaenodon
''Hyaenodon'' (" hyena-tooth") is an extinct genus of carnivorous hyaenodont mammals from tribe Hyaenodontini, within subfamily Hyaenodontinae in family Hyaenodontidae,Malcolm C. McKenna, Susan K. Bell (1997."Classification of Mammals: Above the Species Level" Columbia University Press, New York, 631 pages. that lived in Eurasia and North America during the middle Eocene to early Miocene, existing for about 25.1 million years. Description Typical of early carnivorous mammals, individuals of ''Hyaenodon'' had a very massive skull, but only a small brain. The skull is long with a narrow snout - much larger in relation to the length of the skull than in canine carnivores, for instance. The neck was shorter than the skull, while the body was long and robust and terminated in a long tail. Compared to the generally larger (but not closely related) ''Hyainailouros'', the dentition of ''Hyaenodon'' was geared more towards shearing meat and less towards bone crushing. Some specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proscalops
''Proscalops'' is an extinct genus of insect-eating mammal. Formerly placed in the defunct order Insectivora, it is now placed with the Eulipotyphla. The first and most numerous ''Proscalops'' fossils were found in the Sharps Formation of South Dakota, near Wounded Knee. Other samples have been found in the Brule Formation of South Dakota, the Deep River Formation of Montana, and in Wyoming Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south .... References Prehistoric Eulipotyphla Extinct mammals of North America Oligocene mammals Fossil taxa described in 1901 Prehistoric placental genera {{Paleo-eulipotyphla-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna
Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is '' funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Greek equivalent of fauna. ''Fauna'' is also the word for a book that catalogues the animals in such a manner. The term was first used b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paracrax
''Paracrax'' ("near curassow") is a genus of extinct North American flightless birds, possibly related to modern seriemas and the extinct terror birds. Part of Bathornithidae (though some analysis recover it as closer to the living seriemas instead, or possibly entirely out of Cariamiformes), it is a specialised member of this group, being cursorial carnivores much like their South American cousins, some species attaining massive sizes. Discovery ''Paracrax antiqua'' is the genus type species. The type specimen, YPM 537, was collected in Weld County, Colorado, in 1871 by Othniel Charles Marsh, which identified it as a sort of turkey. It was posteriorly referred to Cracidae by Pierce Brodkorb, before its identity as a bathornithid came to light. Material previously identified as a cormorant, " Phalacrocorax/Oligocrocorax" ''mediterraneus'', was posteriorly identified as ''P. antiqua'' remains. Since then, two more species have been identified: ''P. wetmorei'' and ''P. gigante ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathornis
''Bathornis'' ("tall bird") is an extinct lineage of birds related to modern day seriemas, that lived in North America about 37–20 million years ago. Like the closely related and also extinct phorusrhacids, it was a flightless predator, occupying predatory niches in environments classically considered to be dominated by mammals. It was a highly diverse and successful genus, spanning a large number of species that occurred from the Priabonian Eocene to the Burdigalian Miocene epochs. Description Though most material is highly incomplete, ''Bathornis'' is nonetheless known from a variety of skeletal elements: hindlimbs (most commonly tarso-metatarsals), forelimb elements (especially humeri), pelvises and skulls.Federico L. Agnolin (2009)"Sistemática y Filogenia de las Aves Fororracoideas (Gruiformes, Cariamae)"(PDF). Fundación de Historia Natural Felix de Azara: 1–79. ''Bathornis grallator'' is known from a mostly complete skeleton, including the skull, bearing a proportional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathornithidae
Bathornithidae is an extinct family of birds from the Eocene to Miocene of North America. Part of Cariamiformes, they are related to the still extant seriemas and the also extinct Phorusrhacidae. They were likely similar in habits, being terrestrial, long-legged predators, some of which attained massive sizes. It has been suggested that most, if not all, North American Paleogene cariamiforme fossils are part of this group. Storrs Olson also referred the European ''Elaphrocnemus'' to this clade, though it has since been rejected. Conversely, some analysis have instead recovered them as a polyphyletic group, with ''Bathornis'' and kin being sister taxa to phorusrhacids while ''Paracrax'' is rendered closer to modern seriemas, though this assessment is heavily debated.Mayr, G., & Noriega, J. I. A well-preserved partial skeleton of the poorly known early Miocene seriema ''Noriegavis santacrucensis'' (Aves, Cariamidae). ''Acta palaeontologica Polonica'', 60(3):589-598. The most recent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrarchidae
Centrarchidae, better known as sunfishes, is a family of freshwater ray-finned fish belonging to the order Perciformes (formerly belonging to the deprecated order Centrarchiformes), native only to North America. There are eight universally included genera within the centrarchid family: ''Lepomis'' (true sunfishes), ''Micropterus'' (black basses), ''Pomoxis'' (crappies), ''Enneacanthus'' (banded sunfishes), ''Centrarchus'' (type genus, consisting solely of the flier ''C. macropterus''), ''Archoplites'' ( Sacramento perch), ''Ambloplites'' (rock basses), and ''Acantharchus'' (mud sunfish). A genetic study in 2012 suggests that the highly distinct pygmy sunfishes of the genus ''Elassoma'' are also centarchids. The centrarchid family comprises 38 identified species, 34 of which are extant. It includes many popular game fishes familiar to North American anglers, such as the rock bass, largemouth bass, bluegill, pumpkinseed, green sunfish and crappies. Most sunfish are highly valu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperocyon
''Hesperocyon'' is an extinct genus of canids (subfamily Hesperocyoninae, family Canidae) that was endemic to North America, ranging from southern Canada to Colorado. It appeared during the Uintan age, – Bridgerian age (NALMA) of the Mid-Eocene– 42.5 Ma to 31.0 Ma. ( AEO). ''Hesperocyon'' existed for approximately . Taxonomy ''Hesperocyon'' was assigned to Borophagini by Wang et al. in 1999 and was the earliest of the canids to evolve after the Caniformia-Feliformia split some 42 million years ago. Fossil evidence dates ''Hesperocyon gregarius'' to at least 37 mya, but the oldest ''Hesperocyon'' has been dated at 39.74 mya from the Duchesnean North American land mammal age. The Canidae subfamily Hesperocyoninae probably arose out of ''Hesperocyon'' to become the first of the three great dogs groups: Hesperocyoninae (~40–30 Ma), Borophaginae (~36–2 Ma), and the Caninae lineage that led to the present-day canids (including grey wolves, foxes, coyotes, jackals and dogs). A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nimravids
Nimravidae is an extinct family (biology), family of carnivorans, sometimes known as false saber-toothed cats, whose fossils are found in North America and Eurasia. Not considered to belong to the true cats (family Felidae), the nimravids are generally considered closely related and classified as a distinct family in the suborder Feliformia. Fossils have been dated from the Middle Eocene through the Late Miocene epochs (Bartonian through Tortonian stages, 40.4–7.2 million years ago), spanning about . The barbourofelids, which were formerly classified as a subfamily of the Nimravidae, were reassigned to their own distinct family Barbourofelidae in 2004. However, some recent studies suggest the barbourofelids are a branch of the nimravids, suggesting that this debate might not be settled yet. Morphology and evolution Most nimravids had muscular, low-slung, cat-like bodies, with shorter legs and tails than are typical of cats. Unlike extant taxon, extant Feliformia, the nimravids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saunders_Quarry-1.jpg "Click for more on -> Sandstone")
