The Hale 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 ...

in northern

Arkansas Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the Osage ...

that dates to the Morrowan Series of the early

Pennsylvanian Pennsylvanian may refer to: * A person or thing from Pennsylvania * Pennsylvanian (geology) The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timesca ...

.Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Archived from the original on 31 July 2014. Retrieved 8 July 2014. The Hale Formation has two named members: the Cane Hill and the Prairie Grove Members. The lower member is the Cane Hill, a primarily sandstone and shale interval that unconformably overlies the Mississippian-age

Pitkin Formation The Pitkin Formation, or Pitkin Limestone, is a fossiliferous geologic formation in northern Arkansas that dates to the Chesterian Series of the late Mississippian. This formation was first named the "Archimedes Limestone" by David Dale Owen in ...

. The upper member, the Prairie Grove Member, is predominately limestone and conformably underlies the

Bloyd Formation The Bloyd Formation, or Bloyd Shale, is a geologic formation in Arkansas. It preserves fossils dating back to the Carboniferous period. Stratigraphy The Bloyd Formation conformably overlies the Hale Formation and unconformably underlies the Ato ...

Nomenclature

Named by J. A. Taff in 1905, the Hale Formation was originally called the "Hale sandstone lentil" of the Morrow Formation after Hale Mountain in Washington County, Arkansas. In the same year, George I. Adams and E. O. Ulrich called it the "Hale sandstone member" of the Morrow Formation. In 1907, Albert Homer Purdue raised the rank to the Hale Formation of the Morrow Group, however, the Morrow Group was later abandoned as a stratigraphic unit in 1961. A stratotype was not designated by J. A. Taff and, as of 2017, no reference section has been designated. The Cane Hill Member was named after the town of

Cane Hill Cane Hill Hospital was a psychiatric hospital in Coulsdon in the London Borough of Croydon. The site is owned by GLA Land and Property. History The hospital has its origins as the third Surrey County Pauper Lunatic Asylum, designed by Charle ...

in Washington County, Arkansas in 1953 by Lloyd G. Henbest, who also named its upper member, the Prairie Grove Member, after the town of Prairie Grove, in Washington County, Arkansas. Henbest did not designate a stratotype for either of these members, and as of 2017, neither of them have been designated a reference section. In the eastern parts of the Ozarks in Arkansas, the Hale Formation becomes undifferentiated with the overlying Bloyd Formation and is called the Witts Springs Formation.

Paleontology

Blastoid Blastoids (class Blastoidea) are an extinct type of stemmed echinoderm, often referred to as sea buds. They first appear, along with many other echinoderm classes, in the Ordovician period, and reached their greatest diversity in the Mississi ...
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Pentremites ''Pentremites'' is an extinct genus of blastoid echinoderm belonging to the family Pentremitidae. Description These stalked echinoderms averaged a height of about but occasionally ranged up to about 3 times that size. They, like other blastoid ...

'' *:''P. angustus'' *:''P. rusticus''

Brachiopods

*'' Anthracospirifer'' *''

Antiquatonia ''Antiquatonia'' is an extinct genus of brachiopod belonging to the order Productida and family Productidae. Specimens have been found in Carboniferous beds across many continents, suggesting the genus had a cosmopolitan distribution. Species l ...

''N. A. Heim. 2009. Stability of regional brachiopod diversity structure across the Mississippian/Pennsylvanian boundary. Paleobiology 35(3):393 *''

Beecheria ''Beecheria'' is an extinct genus of brachiopod belonging to the order Terebratulida and family Beecheriidae. Fossils of this genus have been found in Mississippian (geology), Mississippian to Permian beds in Eurasia, Australia, North America, an ...

'' *''

Cleiothyridina ''Cleiothyridina'' is an extinct genus of brachiopods. Species * †''Cleiothyridina accola'' (Reed 1944) * †''Cleiothyridina acutomarginalis'' (Waagen 1883) * †''Cleiothyridina ailakensis'' Reed 1925 * †''Cleiothyridina anabathra'' Wate ...

'' *''

Composita ''Composita'' is an extinct brachiopod genus that lived from the Late Devonian to the Late Permian.

'' *'' Desmoinesia'' *''

Echinaria ''Echinaria'' is a genus of Eurasian and North African plants in the grass family. The only known species is ''Echinaria capitata'', native to the Mediterranean Region as well as the Southwest and Central Asia (from Portugal and Morocco to Kaza ...

'' *'' Hustedia'' *'' Krotovia'' *'' Leptagonia'' *'' Linoproductus'' *'' Neochonetes'' *'' Phricodothyris'' *'' Punctospirifer'' *'' Schizophoria'' *''

Plicochonetes ''Plicochonetes'' is an extinct genus of brachiopods in the extinct family Rugosochonetidae. ''Chonetes ''Chonetes'' is an extinct genus of brachiopods. It ranged from the Late Ordovician to the Middle Jurassic. Species The following s ...

'' *'' Rhipidomella'' *'' Rhynchopora'' *'' Sandia'' *'' Schizophoria'' *'' Spiriferellina'' *'' Tesuquea'' *:''T. morrowensis'' *''

Zia Zia or ZIA (also spelled Ziya, Ḍiya , Dia or Diya) may refer to: People * Zia (name), including a list of people and fictional characters with the name ** A romanization of the Wu ( Shanghainese) pronunciation of the Chinese surname Xie (謝) ...

Bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a l ...
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*'' Fenestella morrowensis'' *:''F. venusta'' *'' Fistulipora matheri'' *'' Matheropora triseriata'' *'' Polypora anastomosa'' *:''P. constricta'' *:''P. halensis'' *:''P. magna'' *:''P. purduei'' *:''P. reversispina'' *:''P. triseriata'' *:''P. washingtonensis'' *'' Phyllopora perforata'' *'' Septopora crebripora'' *'' Sulcoretepora brentwoodensis'' *:''S. sinuomarginata''

Cephalopod A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...
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*'' Arkanites relictus''W. L. Manger and W. B. Saunders. 1980. Lower Pennsylvanian (Morrowan) ammonoids from the North American midcontinent. Palentological Society Memoirs. 10:1-56 *'' Bactrites redactus'' M. Gordon. 1964. Carboniferous Cephalopods of Arkansas. Unitest States Geological Survey Professional Paper. 460:1-322 *:''B. gaitherensis'' *'' Baschkirites'' *:''B. librovitchi'' *'' Bisatoceras secundum'' *'' Branneroceras branneri'' *'' Cancelloceras huntsvillense'' *'' Cymoceras cracens'' *'' Dinocycloceras prolixum'' *''

Endolobus ''Endolobus'' is an extinct genus from the nautiloid order, Nautilida. Nautiloids are a subclass of shelled cephalopods that were once diverse and numerous but are now represented by only a handful of species, including '' Nautilus''. ''Endolu ...

'' *'' Ephippioceras ferratum'' *'' Glaphyrites morrowensis'' *'' Gordonites matheri'' *:''G. filifer'' *'' Homoceratoides cracens'' *'' Hudsonoceras moorei'' *'' Knightoceras oxylobatum'' *:''K. palatum'' *'' Paradimorphoceras'' *'' Proshumardites morrowanus'' *'' Pseudopronorites quinni'' *:''P. arkansiensis'' *'' Pseudorthoceras knoxense'' *'' Quinnites henbetsi'' *:''Q. textum'' *'' Ramosites'' *'' Reticuloceras wainwrighti'' *:''R. tiro'' *:''R. semiretia'' *'' Retites semiretia'' *'' Schartymites paynei'' *'' Syngastrioceras globosum'' *:''S. oblatum'' *'' Verneuilites pygmaeus'' *'' Wiedeyoceras matheri''

Conodont Conodonts (Greek ''kōnos'', "cone", + ''odont'', "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, which ...
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Gondolella ''Gondolella'' is an extinct genus of conodonts in the family Gondolellidae Gondolellidae is an extinct family of conodonts in the order Ozarkodinida. There are three subfamilies: Mullerinae, Neogondolellinae and Novispathodinae. Refe ...

'' *:''G. clarki'' *''

Idiognathodus ''Idiognathodus'' is an extinct conodont genus in the family Idiognathodontidae. Use in stratigraphy The species ''Idiognathodus simulator'' made its first appearance during the Gzhelian, the youngest age of the Pennsylvanian (late Carbonife ...

'' *:''I. klapperi'' *:''I. sinuosus'' *''

Idiognathoides ''Idiognathoides'' is an extinct genus of conodonts. Glen K. Merrill stated in 1963 that "conodont workers have considered ''Idiognathoides'' to be a junior synonym of '' Polygnathodella'' but it now proves to be a junior synonym of ''Cavusgnat ...

'' *:''I. convexus'' *:''I. sinuatus'' *''

Neognathodus ''Neognathodus'' is an extinct genus of conodonts. Use in stratigraphy The Bashkirian, the oldest age of the Pennsylvanian (also known as Upper Carboniferous), contains six biozones based on conodont index fossils, two of which contain ''Neo ...

'' *:''N. bassleri'' *:''N. symmetricus'' *'' Rhachistognathus'' *:''R. primus''

Crinoids

*'' Arkacrinus'' *'' Eirmocrinus'' *'' Palmerocrinus''

Flora Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous) native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' gut flora'' or '' skin flora''. E ...

*''

Archaeolithophyllum ''Archaeolithophyllum'' is a genus of conceptacle-bearing red alga that falls in the coralline stem group. It somewhat resembles ''Lithophyllum.'' As of today, ''Archaeolithophyllum'' is the only Palaeozoic coralline to bear clear conceptacles, ...

'' *:''A. missouiense'' *'' Asphaltina'' *:''A. cordillerensis'' *'' Eflugelia'' *''

Girvanella ''Girvanella'' is a fossil thought to represent the calcified sheath of a filamentous cyanobacterium known from the Burgess Shale and other Cambrian fossil deposits. ''Girvanella'' was originally described as a foraminifera. It was later assigne ...

'' *'' Stacheoides'' *:''S. spissa''

Foraminifera Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and ot ...

*'' Asteroarchaediscus'' *:''A. rugosus'' *'' Biseriella'' *'' Climacammina'' *:''C. antiqua'' *'' Diplosphaerina'' *:''D. inaequalis'' *'' Earlandia'' *'' Endothyra'' *'' Eosigmoinina'' *:''E. rugosa'' *''

Eostaffella ''Eostaffella'' is an extinct genus of fusulinid belonging to the family Eostaffellidae. Specimens of the genus have been found in Carboniferous to Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million ...

'' *:''E. pinguis'' *'' Hemiarchaediscus'' *''

Millerella ''Millerella'' is an extinct genus of fusulinid belonging to the family Eostaffellidae. Fossils of the genus have been found in Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years ...

'' *:''M. marblensis'' *:''M. pressa'' *'' Neoarchaediscus'' *'' Paleonubecularia'' *'' Paramillerella'' *:''P. pinuis'' *'' Planoendothyra'' *'' Plectogyra'' *:''P. tantala'' *'' Pseudoglomospira'' *''

Tetrataxis ''Tetrataxis'' is a genus of plant in family Lythraceae. The sole species is ''Tetrataxis salicifolia''. It is endemic to Mauritius. Its natural habitat is subtropical or tropical dry forest A forest is an area of land dominated by tree ...

'' *:''T. maxima'' *'' Tubertina'' *:''T. plana'' *'' Turrispoiroides'' *:''T. multivolutus''

Ostracod Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typic ...
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*'' Glyptopleua'' *: ''G. whitei'' *'' Healdia'' *'' Kirkbyella (Berdanella)'' *'' Knightina'' *'' Shivaella''

Trace Fossils A trace fossil, also known as an ichnofossil (; from el, ἴχνος ''ikhnos'' "trace, track"), is a fossil record of biological activity but not the preserved remains of the plant or animal itself. Trace fossils contrast with body fossils, ...

*'' Gastrochaenolites anauchen''M. A. Wilson and T. J. Palmer. 1998. The earliest Gastrochaenolites (Early Pennsylvanian, Arkansas, USA): An Upper Paleozoic bivalve boring?. Journal of Paleontology. 72(4):769-772 *'' Trypanites''

Incertae sedis

*'' Clacisphaera'' *:''C. laevis'' *'' Proninella'' *:''P. strigosa''

References

{{reflist Carboniferous Kansas Carboniferous Arkansas Carboniferous southern paleotropical deposits