Runningwater Formation | |
---|---|
Stratigraphic range: Early Miocene (Hemingfordian) ~ | |
Type | Formation |
Lithology | |
Primary | Sandstone |
Other | Conglomerate |
Location | |
Coordinates | 42°24′N103°00′W / 42.4°N 103.0°W |
Approximate paleocoordinates | 43°06′N99°06′W / 43.1°N 99.1°W |
Region | Nebraska |
Country | ![]() |
The Runningwater Formation is a geologic formation in Nebraska. It preserves fossils dating back to the Hemingfordian of the Early Miocene of the Neogene period. The sandstones and conglomerates of the formation were deposited in a fluvial environment. The formation has provided many fossil mammals.
Among the following fossils have been found in the formation: [1]
Menoceras is a genus of extinct, small rhinocerotids endemic to most of southern North America and ranged as far south as Panama during the early Miocene epoch. It lived from around 30.7—19.7 Ma, existing for approximately 11 million years.
Amphicyon is an extinct genus of large carnivorans belonging to the family Amphicyonidae, subfamily Amphicyoninae, from the Miocene epoch. Members of this family received their vernacular name for possessing bear-like and dog-like features. They ranged over North America, Europe, Asia, and Africa.
Daeodon is an extinct genus of entelodont even-toed ungulates that inhabited North America about 23 to 20 million years ago during the latest Oligocene and earliest Miocene. The type species is Daeodon shoshonensis, described by a very questionable holotype by Cope. Some authors synonymize it with Dinohyus hollandi and several other species, but due to the lack of diagnostic material, this is questionable at best.
Daphoenus is an extinct genus of amphicyonids. Daphoenus inhabited North America from the Late Eocene to the Middle Miocene, 37.2—16.0 Mya, existing for approximately 21 million years.
The John Day Formation is a series of rock strata exposed in the Picture Gorge district of the John Day River basin and elsewhere in north-central Oregon in the United States. The Picture Gorge exposure lies east of the Blue Mountain uplift, which cuts southwest–northeast through the Horse Heaven mining district northeast of Madras. Aside from the Picture Gorge district, which defines the type, the formation is visible on the surface in two other areas: another exposure is in the Warm Springs district west of the uplift, between it and the Cascade Range, and the third is along the south side of the Ochoco Mountains. All three exposures, consisting mainly of tuffaceous sediments and pyroclastic rock rich in silica, lie unconformably between the older rocks of the Clarno Formation below and Columbia River basalts above.
Parictis is an extinct arctoid belonging to the family Subparictidae.
Rhineura is a genus of worm lizard endemic to North America. The genus has only one extant species but more are known from fossil record. They are also known as the North American worm lizards.
Metatomarctus is an extinct genus of the Borophaginae subfamily of canids native to North America. It lived during the Early to Middle Miocene, 23–16 Mya, existing for approximately 7 million years It was an intermediate-size canid, and more predaceous than earlier borophagines.
Temnocyon is an extinct genus of amphicyonids endemic to North America. It lived from the Oligocene to Early Miocene approximately 30.8—20.4 mya, existing for about 11 million years.
Cynelos is a large extinct genus of amphicyonids which inhabited North America, Europe, and Africa from the Early Miocene subepoch to the Late Miocene subepoch 20.4–13.7 Mya, existing for approximately 6 million years.
Merychyus is an extinct genus of oreodont of the family Merycoidodontidae, endemic to North America. It lived during the Miocene, 20.4—10.3 mya, existing for approximately 10 million years. Fossils are widespread through the central and western United States.
Ysengrinia is an extinct genus of carnivoran in the family Amphicyonidae (beardogs), which lived in Europe, Asia, and North America during the Early Miocene. It was also reported from Egypt and Namibia, but this material has been reassigned to other genera of beardogs.
Livyatan is an extinct genus of macroraptorial sperm whale containing one known species: L. melvillei. The genus name was inspired by the biblical sea monster Leviathan, and the species name by Herman Melville, the author of the famous novel Moby-Dick about a white bull sperm whale. Herman Melville often referred to whales as "Leviathans" in his book. It is mainly known from the Pisco Formation of Peru during the Tortonian stage of the Miocene epoch, about 9.9–8.9 million years ago (mya); however, finds of isolated teeth from other locations such as Chile, Argentina, United States (California), South Africa and Australia imply that either it or a close relative survived into the Pliocene, around 5 mya, and may have had a global presence. It was a member of a group of macroraptorial sperm whales and was probably an apex predator, preying on whales, seals and so forth. Characteristically of raptorial sperm whales, Livyatan had functional, enamel-coated teeth on the upper and lower jaws, as well as several features suitable for hunting large prey.
Paleontology in Nebraska refers to paleontological research occurring within or conducted by people from the U.S. state of Nebraska. Nebraska is world-famous as a source of fossils. During the early Paleozoic, Nebraska was covered by a shallow sea that was probably home to creatures like brachiopods, corals, and trilobites. During the Carboniferous, a swampy system of river deltas expanded westward across the state. During the Permian period, the state continued to be mostly dry land. The Triassic and Jurassic are missing from the local rock record, but evidence suggests that during the Cretaceous the state was covered by the Western Interior Seaway, where ammonites, fish, sea turtles, and plesiosaurs swam. The coasts of this sea were home to flowers and dinosaurs. During the early Cenozoic, the sea withdrew and the state was home to mammals like camels and rhinoceros. Ice Age Nebraska was subject to glacial activity and home to creatures like the giant bear Arctodus, horses, mammoths, mastodon, shovel-tusked proboscideans, and Saber-toothed cats. Local Native Americans devised mythical explanations for fossils like attributing them to water monsters killed by their enemies, the thunderbirds. After formally trained scientists began investigating local fossils, major finds like the Agate Springs mammal bone beds occurred. The Pleistocene mammoths Mammuthus primigenius, Mammuthus columbi, and Mammuthus imperator are the Nebraska state fossils.
Ochotona spanglei is an extinct species of pika, known from Late Miocene - Early Pliocene fossil from Oregon (USA). Fossils were also found in Nebraska referred to as Ochotona cf. spanglei.
The Alachua Formation is a Miocene geologic formation in Florida. The claystones, sandstones and phosphorites of the formation preserve many fossils of mammals, birds, reptiles and fish, among others megalodon.
Phlaocyon yatkolai is an extinct species of canid mammal known from the early Hemingfordian Runningwater Formation, Box Butte County, Nebraska (42.2°N 103.1°W, paleocoordinates 42.9°N 99.2°W).
Miocochilius is an extinct genus of small notoungulate mammals (typotheres) native to South America. The genus lived during the Middle Miocene epoch. The genus contains two described species, the type species M. anomopodus described in 1953 by Ruben Arthur Stirton and M. federicoi, described and included in the genus by Darin A. Croft.
Asilifelis is an extinct genus of small felid that lived in what is now Kenya during the Early Miocene. Despite its fragmentary remains, it is remarkable because of its small size and advanced dentition. It contains a single species, Asilifelis cotae.
Myacyon is an extinct genus of large sized carnivoran mammals, belonging to the family Amphicyonidae, that lived in Africa during the Miocene epoch. Due to the limited scope and fragmentary nature of the severely damaged holotype, as well as the illustrations in its descriptions, which have been called inadequate, usage of this genus poses serious issues. However, it is notable for being one of the last surviving members of its family and its adaptions to hypercarnivory. Its relationships to other amphicyonids are obscure, and it is not closely related to Bonisicyon, the other late surviving African genus, although it has been proposed that it descends from a species of Cynelos or Namibiocyon.