The Runningwater Formation is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

. It preserves

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

dating back to the

Hemingfordian The Hemingfordian on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 20,600,000 to 16,300,000 years BP. It is usually considered to overlap the lates ...

of the

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

of the

Neogene The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of th ...

period Period may refer to: Common uses * Period (punctuation) * Era, a length or span of time *Menstruation, commonly referred to as a "period" Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (o ...

. The

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

s and conglomerates of the formation were deposited in a

fluvial A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

environment. The formation has provided many fossil mammals.

Fossil content

Among the following fossils have been found in the formation:Runningwater Formation
at

Fossilworks Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cr ...

.org ;Mammals * '' Aletomeryx gracilis'' * '' Arretotherium fricki'' * '' Barbouromeryx trigonocorneus'' * '' Cynarctoides acridens'' * '' Cynelos stenos''Hunt & Yatkola, 2020 * '' Diceratherium niobrarense'' * '' Daphoenodon (Borocyon) robustum'' * '' Desmocyon thomsoni'' * '' Hypertragulus minor'' * '' Menoceras barbouri'' * '' Merychyus arenarum'', '' M. elegans'' * '' Metatomarctus canavus'' * '' Osbornodon iamonensis'' * '' Pseudoblastomeryx advena'' * '' Anchitheriomys stouti'' * '' Desmatippus tyleri'' * '' Edaphocyon lautus'' * '' Amphicyon galushai'' * '' Craterogale cf. simus'' * '' Leptarctus cf. ancipidens'' * '' Leptocyon vulpinus'' * '' Tephrocyon scitulus'' * '' Merycochoerus proprius'' ;Reptiles * '' Macrochelys schmidti'' * '' Rhineura marslandensis'' * '' Sceloporus sp.''

References

Bibliography

* {{citation , first=Robert M. , last=Hunt Jr , first2=Daniel A. , last2=Yatkola , year=2020 , title=A new species of the amphicyonid carnivore ''Cynelos'' Jourdan, 1862 from the early Miocene of North America , url=http://sciencepress.mnhn.fr/en/periodiques/geodiversitas/42/5 , journal=

Geodiversitas The French National Museum of Natural History ( ; abbr. MNHN) is the national natural history museum of France and a of higher education part of Sorbonne University. The main museum, with four galleries, is located in Paris, France, within the Ja ...

, volume=42 , issue=5 , pages=57–67 , doi=10.5252/geodiversitas2020v42a5 Geologic formations of Nebraska Neogene geology of Nebraska Miocene Series of North America Hemingfordian Aquitanian (stage) Burdigalian Sandstone formations of the United States Conglomerate formations of the United States Fluvial deposits Fossiliferous stratigraphic units of North America Paleontology in Nebraska Formations Formations

Fossil content

See also

References

Bibliography