Pitkin Formation

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	Fossilized skeleton of Archimedes Bryozoan.

Pitkin Formation
Stratigraphic range: Upper Visean-Serpukhovian^[1]
Pitkin Formation; Stratigraphic range: Upper Visean-Serpukhovian
Type	Formation
Sub-units	Imo Shale
Underlies	Hale Formation
Overlies	Fayetteville Formation
Thickness	up to and over 400 feet
Lithology
Primary	Limestone
Other	Shale
Location
Region	Arkansas
Country	United States
Type section
Named for	Pitkin post office, Washington County, Arkansas
Named by	George Irving Adams and Edward Oscar Ulrich

The Pitkin Formation, or Pitkin Limestone, is a fossiliferous geologic formation in northern Arkansas that dates to the Chesterian Series of the late Mississippian.^[4] This formation was first named the "Archimedes Limestone" by David Dale Owen in 1858, but was replaced in 1904.^[3] The Pitkin conformably overlies the Fayetteville Shale and unconformably underlies the Pennsylvanian-age Hale Formation. Some workers have considered the top of the Pitkin Formation to be a separate formation called the Imo Formation. However more recently, others have considered it as an informal member of the Pitkin Formation.

Paleofauna[]

Early work aimed at creating a comprehensive list for all fossils found in the Pitkin Formation was done by Easton in 1943.^[1] Unless otherwise stated, all species below can be found in his 'Fauna of the Pitkin Formation.'

Formanifera[]

A. stilus^[5]

A. rugosus^[5]

Earlandia^[5]
Endothyra^[1]

E. kleina^[6]

E. phrissa^[5]

^[6]

E. explicata^[5]

E. rugosa^[5]

Eostaffella^[5]
^[5]
^[5]

^[5]
^[5]
^[6]
^[5]
^[6]
^[5]

P. priscus^[5]

^[5]
Tetrataxis^[5]

T. corona^[6]

^[5]

Z. designata^[5]

Z. discoidea^[5]

Porifera, Sponges[]

A modern Cliona from the coastal waters of northern France.

Cliona

Scyphozoa[]

Originally considered to be a gastropod.

Anthozoa, Corals[]

Aulopora

A. gracilis

C. variablilis

^[7]
^[7]
^[7]

L. major

L. minor

^[8]

M. macerimuris^[8]

^[7]
Pleurodictyum

P. eugenei

P. meekanum

Syringopora
Triplophyllum

Aulopora from the Silica Formation of Ohio.
Pleurodictyum americanum from the Givetian Kashong Shale (Hamilton Group) of Livingston County, New York.
Syringopora from the Boone Formation of Arkansas.

Blastoidea[]

Pentremites godoni from the Lower Carboniferous of Illinois.

Pentremites

P. elongatus^[9]

P. godoni^[9]

P. laminatus^[9]

P. obesus^[9]

P. platybasis^[1]

Crinoidea, Sea Lilies[]

(see unidentified section)

A. patulus ^[10]

A. planus^[10]

B. figuratus^[10]

^[10]

C. stevensi^[10]

^[10]

C. eventus^[10]

^[10]

L. floweri^[10]

Onychocrinus

O. pulaskiensis^[10]

P. aptus^[10]

P. durus^[10]

P. pitkini^[10]

P. stereostoma^[10]

P. modulus^[10]

^[10]

P. cooksoni^[10]

P. irregularis^[10]

P. tridecibrachiatus^[10]

Scytalocrinus (see unidentified section)

S. braggsi^[10]

S. dunlapi^[10]

S. garfieldi^[10]

Taxocrinus

T. whitfieldi^[10]

T. caespes

T. residuus

Z. foveatus

Cyathocrinus goniodactylus, on display at Galerie de paléontologie et d'anatomie comparée in Paris.
Fossil of Scytalocrinus from Carboniferous of the United States

Ophiuroidea, Brittle Stars[]

This group was originally place under Stelleroidia in early studies.^[1]

A. singulatus

Echinoidea, Sea Urchins[]

An upper Carboniferous species of Archaeocidaris.

Archaeocidaris

Worms[]

Previous studies have grouped these diverse animals into a single, obsolete taxon: Vermes.^[1]

Spirorbis

Bryozoa, "Moss-animals"[]

A. solida ^[1]

Archimedes (called Archimedipora in early studies)^[1]

A. communis ^[1]^[11]

A. compactoides ^[11]

A. compactus ^[11]

A. distans ^[1]^[11]

A. fosteri ^[11]

A. fragilis ^[11]

A. intermedia (A. intermedius) ^[1]^[11]

A. invaginata (A. invaginatus) ^[1]^[11]

A. lunatus ^[11]

A. magnus ^[11]

A. meekanus ^[11]

A. moorei ^[11]

A. pitkinensis ^[11]

A. proutana (A. proutanus) ^[1]^[11]

A. sublaxus ^[11]

A. swallovana (A. swallovanus) ^[1]^[11]

A. terebriformis ^[11]

^[1]

C. distans ^[11]

C. regularis ^[1]

D. levis ^[1]^[11]

Dyscritella ^[1]
Fenestella ^[1]

F. cumingsi ^[11]

F. matheri ^[11]

F. rectangularis ^[11]

F. serratula ^[11]

F. tenax ^[11]

F. introspinosa ^[1]^[11]

G. crassa ^[1]^[11]

G. michilinia ^[1]^[11]

L. solida ^[1]^[11]

M. abrupta ^[1]^[11]

M. tenuis ^[1]^[11]

P. whitei ^[1]

Rhombopora ^[1]
Septopora

S. biserialis ^[1]

S. cestriensis ^[1]

S. subquadrans ^[1]

T. cestriensis ^[1]^[11]

T. microfistulata ^[1]^[11]

T. poculoformis ^[1]^[11]

T refiexa ^[1]^[11]

T. subtilis ^[1]^[11]

A Devonian Fenestella from Belgium.

Brachiopoda[]

A. suspectum ^[12]

Athyris

A. cestriensis

B. arkansana

C. cestriensis

C explanata

Chonetes

C. oklahomensis

C. sericeus

C. tumescens

C. sublamellosa
Composita (See unidentified section)

C. subquadrata

C. trinuclea

Crania

C. infimbriata

Diaphragmus

D. arkansanum

D. formosum

D. illinoisensis

D. shumardanum

D. whitfieldi

(See unidentified section)

E. alternatus

E. costata

E. pitkinensis

E. vera

G. indianensis

H. multicostata

K. lucerna

Lingula

L. newberryi var. moorefieldana and ovata

Linoproductus

L. pileiformis

Martinia

O. kaskaskiensis

O. stenopsis^[12]

O. subglobosus (var. protensa)

O. uspectum

Productus

P. cestriensis

P. fasciculatus

Pustula

R. setigera

Spirifer

S. leidyi

S. pellaensis

Spiriferina

S. spinosa

S. aequalis

T. neogenes

Bivalvia, Bivalves[]

This group was also referred to by another name in earlier studies: Pelecypoda.^[1]

A. walkeri

Aviculopecten

A. batesvillensis

A. eurekensis

A. keoughensis

A. morrowensis

A. multilineatus

A. pitkinensis

Conocardium

C. peculiare

(See unidentified section)

E. crassa (Along with E. crassa var. suborbiculoidea)

E. pitkinensis

L. vaseyana

Leiopteria
Leptodesma

M. compressa

M. longicardinalis

Nucula

N. illinoisensis

Schizodus (See unidentified section)

S. arkansanus

S. chesterensis

S. depressus

S. insignis

S. cherokeense

S. gibsonense

S. quadriplicatum

Scaphopoda, Tusk Shells[]

Laevidentalium

Gastropoda, Snails[]

Bellerophon (See unidentified section)
B. pitkinensis
Euphemites

E. incarinatus

(See unidentified section)

Helcionopsis

H. reticulatus

Holopea

H. newtonensis

(See unidentified section)

M. angulata

Naticopsis
Platyceras

P. subrotundum

S. subcorpulenta

S. planidorsatus

S. triliris

(See unidentified section)

Cephalopoda[]

Arcanoceras

A. furnishi^[13]

(see unidentified section)
Cravenoceras

C. hesperium

C. richardsonianum^[13]

Cycloceras

C. randolphensis

C. equoyahensis

Dolorthoceras (See unidentified section)

D. eurekensis

E. globosus

E. bisulcatum^[13]

^[13]
^[13]
^[13]

Trilobita[]

G. pustulosus

K. chesterensis

K. pitkinensis^[14]

Paladin

P. mucronatus

Ostracoda[]

G. optina

P. fayettevillensis

Vertebrata[]

Cladodus
Petalodus

Plantae, Plants[]

"Encrusting Algae" has been reported but not assigned to any genus.^[1]

Archaeolithophyllum^[6]

A. cordillerensis^[5]

Girvanella^[5]
^[5]

Unidentified[]

Following is a list of fossils also found in the Pitkin by Easton in 1943 that have gone unidentified.^[1]

A "Cup Coral"
A member of the genus Pentremites
Three species within Agassizocrinus
Two species within Scytalocrinus
A totally unidentifiable Crinoid
Two species of Bellerophon
Two species of Gosseletina
Two species of Leptoptygma
Two Species of Strobeus
One species each of Composita and Echinoconchus
Two species of Cypricardella
Two species of Coloceras, one of which may actually be
One species of Dolorthoceras
An unnamed shark spine

References[]

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai ^aj ^ak ^al ^am Easton, William H., The Fauna of the Pitkin Formation of Arkansas., Journal of Paleontology: vol. 17:2. March, 1943.
^ McFarland, John David (2004) [1998]. "Stratigraphic summary of Arkansas" (PDF). Arkansas Geological Commission Information Circular. 36: 12–13. Archived from the original (PDF) on 2016-12-21. Retrieved 2018-05-31.
^ ^a ^b Adams, G.; Ulrich, E. (1904). "Zinc and lead deposits of northern Arkansas". U.S. Geological Survey Professional Paper. 24: 27, 109.
^ Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to thefix Paleobiology Database". Retrieved 17 December 2021. {{cite web}}: |author= has generic name (help)
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v Brenckle, Paul (1977). "Foraminifers and other calcareous microfossils from Late Chesterian (Mississippian) strata of northern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 73–87. Retrieved 3 February 2018.
^ ^a ^b ^c ^d ^e ^f Nodine-Zeller, Doris E. (1977). "Microfauna from Chesterian (Mississippian) and Morrowan (Pennsylvanian) rocks in Washington County, Arkansas, and Adair and Muskogee Counties, Oklahoma" (PDF). Oklahoma Geological Survey Guidebook. 18: 89–99. Retrieved 3 February 2018.
^ ^a ^b ^c ^d Webb, Gregory., 1987., The Coral Fauna of the Pitkin Formation (Chesterian), Northeastern Oklahoma and Northwestern Arkansas. Journal of Paleontology vol. 61:3
^ ^a ^b Webb., Gregory., 1990., A New Tabulate Coral Species from the Pitkin Formation (Chesterian) of north-central Arkansas. Journal of Paleontology vol. 64:4.
^ ^a ^b ^c ^d Horowitz, Alan S.; Macurda Jr, D. B. (1977). "Late Mississippian and Early Pennsylvanian blastoids from northeastern Oklahoma and northwestern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 169–170. Retrieved 31 January 2018.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x Strimple, Harrell L. (1977). "Chesterian (Upper Mississippian) and Morrowan (Lower Pennsylvanian) crinoids of northeastern Oklahoma and northwestern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 171–176. Retrieved 30 January 2018.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai Horowitz, Alan S. (1977). "Late Mississippian and Early Pennsylvanian bryozoan faunas of Arkansas and Oklahoma: a review" (PDF). Oklahoma Geological Survey Guidebook. 18: 101–105. Retrieved 3 February 2018.
^ ^a ^b Henry, Thomas W.; Gordon Jr., Mackenzie (January 1985). "Chesterian davidsoniacean and orthotetacean brachiopods, Ozark region of Arkansas and Oklahoma". Journal of Paleontology. 59 (1): 32–59. JSTOR 1304826.
^ ^a ^b ^c ^d ^e ^f Saunders, W. Bruce; Manger, Walter L.; Gordon Jr., Mackenzie (1977). "Upper Mississippian and Lower and Middle Pennsylvanian ammonoid biostratigraphy of northern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 117–137. Retrieved 1 February 2018.
^ Brezinski, David K. (31 March 2017). "Some New Late Mississippian Trilobites from Oklahoma and Arkansas". Annals of Carnegie Museum. 84 (2): 173–178. doi:10.2992/007.084.0203.

[easton-1] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai ^aj ^ak ^al ^am Easton, William H., The Fauna of the Pitkin Formation of Arkansas., Journal of Paleontology: vol. 17:2. March, 1943.

[McFarland-2] McFarland, John David (2004) [1998]. "Stratigraphic summary of Arkansas" (PDF). Arkansas Geological Commission Information Circular. 36: 12–13. Archived from the original (PDF) on 2016-12-21. Retrieved 2018-05-31.

[AdamsUlrich-3] Adams, G.; Ulrich, E. (1904). "Zinc and lead deposits of northern Arkansas". U.S. Geological Survey Professional Paper. 24: 27, 109.

[web1-4] Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to thefix Paleobiology Database". Retrieved 17 December 2021. {{cite web}}: |author= has generic name (help)

[Brenckle-5] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v Brenckle, Paul (1977). "Foraminifers and other calcareous microfossils from Late Chesterian (Mississippian) strata of northern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 73–87. Retrieved 3 February 2018.

[Nodine-Zeller-6] ^ ^a ^b ^c ^d ^e ^f Nodine-Zeller, Doris E. (1977). "Microfauna from Chesterian (Mississippian) and Morrowan (Pennsylvanian) rocks in Washington County, Arkansas, and Adair and Muskogee Counties, Oklahoma" (PDF). Oklahoma Geological Survey Guidebook. 18: 89–99. Retrieved 3 February 2018.

[webb-7] Webb, Gregory., 1987., The Coral Fauna of the Pitkin Formation (Chesterian), Northeastern Oklahoma and Northwestern Arkansas. Journal of Paleontology vol. 61:3

[webb2-8] Webb., Gregory., 1990., A New Tabulate Coral Species from the Pitkin Formation (Chesterian) of north-central Arkansas. Journal of Paleontology vol. 64:4.

[HorowitzMacurda-9] Horowitz, Alan S.; Macurda Jr, D. B. (1977). "Late Mississippian and Early Pennsylvanian blastoids from northeastern Oklahoma and northwestern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 169–170. Retrieved 31 January 2018.

[Strimple-10] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x Strimple, Harrell L. (1977). "Chesterian (Upper Mississippian) and Morrowan (Lower Pennsylvanian) crinoids of northeastern Oklahoma and northwestern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 171–176. Retrieved 30 January 2018.

[Horowitz-11] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z ^aa ^ab ^ac ^ad ^ae ^af ^ag ^ah ^ai Horowitz, Alan S. (1977). "Late Mississippian and Early Pennsylvanian bryozoan faunas of Arkansas and Oklahoma: a review" (PDF). Oklahoma Geological Survey Guidebook. 18: 101–105. Retrieved 3 February 2018.

[HenryGordon1985-12] Henry, Thomas W.; Gordon Jr., Mackenzie (January 1985). "Chesterian davidsoniacean and orthotetacean brachiopods, Ozark region of Arkansas and Oklahoma". Journal of Paleontology. 59 (1): 32–59. JSTOR 1304826.

[Saunders-13] ^ ^a ^b ^c ^d ^e ^f Saunders, W. Bruce; Manger, Walter L.; Gordon Jr., Mackenzie (1977). "Upper Mississippian and Lower and Middle Pennsylvanian ammonoid biostratigraphy of northern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 117–137. Retrieved 1 February 2018.

[14] Brezinski, David K. (31 March 2017). "Some New Late Mississippian Trilobites from Oklahoma and Arkansas". Annals of Carnegie Museum. 84 (2): 173–178. doi:10.2992/007.084.0203.

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