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.[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.

Pitkin Formation
Stratigraphic range: Upper Visean-Serpukhovian[1]
TypeFormation
Sub-unitsImo Shale
UnderliesHale Formation
OverliesFayetteville Formation
Thicknessup to and over 400 feet[2]
Lithology
PrimaryLimestone[1]
OtherShale
Location
RegionArkansas
CountryUnited States
Type section
Named forPitkin post office, Washington County, Arkansas[3]
Named byGeorge Irving Adams and Edward Oscar Ulrich

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
  • Archaediscus
A. stilus[5]
  • Asteroarchaediscus
A. rugosus[5]
E. kleina[6]
E. phrissa[5]
  • Endothyranella[6]
  • Eosigmoilina
E. explicata[5]
E. rugosa[5]
P. priscus[5]
T. corona[6]
  • Trepeilopsis[5]
  • Zellerina
Z. designata[5]
Z. discoidea[5]

Porifera, Sponges
A modern Cliona from the coastal waters of northern France.

Scyphozoa
  • Conularia Originally considered to be a gastropod.

Anthozoa, Corals
A. gracilis
  • Caninostrotion
C. variablilis
  • Kinkaidia[7]
  • Lesliella[7]
  • Leonardophyllum[7]
  • Lonsdaleia
L. major
L. minor
M. macerimuris[8]
P. eugenei
P. meekanum

Blastoidea
Pentremites godoni from the Lower Carboniferous of Illinois.
P. elongatus[9]
P. godoni[9]
P. laminatus[9]
P. obesus[9]
P. platybasis[1]

Crinoidea, Sea Lilies
  • Agassizocrinus (see unidentified section)
A. patulus [10]
  • Aphelecrinus
A. planus[10]
  • Bronaughocrinus
B. figuratus[10]
  • Camptocrinus[10]
  • Carinocrinus
C. stevensi[10]
  • Castillocrinus
  • Catillocrinus[10]
  • Cosmetocrinus
C. eventus[10]
L. floweri[10]
O. pulaskiensis[10]
  • Pachylocrinus
  • Paianocrinus
P. aptus[10]
P. durus[10]
  • Paracymbiocrinus
P. pitkini[10]
  • Pelecocrinus
P. stereostoma[10]
  • Pentaramicrinus
P. modulus[10]
  • Phacelocrinus[10]
  • Phanocrinus
P. cooksoni[10]
P. irregularis[10]
  • Poteriocrinus
  • Pterotocrinus
P. tridecibrachiatus[10]
S. braggsi[10]
S. dunlapi[10]
S. garfieldi[10]
T. whitfieldi[10]
  • Telikosocrinus
T. caespes
T. residuus
  • Zeusocrinus
Z. foveatus

Ophiuroidea, Brittle Stars

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

  • Aganaster
A. singulatus
  • Schoenaster

Echinoidea, Sea Urchins
An upper Carboniferous species of Archaeocidaris.

Worms

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

Bryozoa, "Moss-animals"
Stereo image
Left frame 
Right frame 
Parallel view ()
Cross-eye view ()
Fossilized skeleton of Archimedes Bryozoan.
  • Anisotrypa
A. solida [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]
  • Batostomella [1]
  • Chellotrypa
C. distans [11]
  • Chilotrypa
C. regularis [1]
  • Dichotrypa
D. levis [1][11]
F. cumingsi [11]
F. matheri [11]
F. rectangularis [11]
F. serratula [11]
F. tenax [11]
  • Fistulipora
F. introspinosa [1][11]
  • Glyptopora
G. crassa [1][11]
G. michilinia [1][11]
  • Lyropora
L. solida [1][11]
  • Meekopora
M. abrupta [1][11]
M. tenuis [1][11]
  • Polypora
P. whitei [1]
S. biserialis [1]
S. cestriensis [1]
S. subquadrans [1]
  • Tabulopora
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
  • Adectorhynchus
A. suspectum [12]
A. cestriensis
  • Buxtonia
B. arkansana
  • Camarophoria
C. cestriensis
C explanata
C. oklahomensis
C. sericeus
C. tumescens
Cliothyridina
  • C. sublamellosa
  • Composita (See unidentified section)
C. subquadrata
C. trinuclea
C. infimbriata
D. arkansanum
D. formosum
D. illinoisensis
D. shumardanum
D. whitfieldi
E. alternatus
  • Eumetria
E. costata
E. pitkinensis
E. vera
  • Girtyella
G. indianensis
  • Hustedia
H. multicostata
  • Krotavia
K. lucerna
L. newberryi var. moorefieldana and ovata
L. pileiformis
O. kaskaskiensis
O. stenopsis[12]
O. subglobosus (var. protensa)
O. uspectum
P. cestriensis
P. fasciculatus
R. setigera
S. leidyi
S. pellaensis
S. spinosa
  • Streptorhynchus
  • Syringothyris
S. aequalis
  • Tetracamera
T. neogenes

Bivalvia, Bivalves

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

  • Allorisma
A. walkeri
A. batesvillensis
A. eurekensis
A. keoughensis
A. morrowensis
A. multilineatus
A. pitkinensis
C. peculiare
  • Cypricardella (See unidentified section)
  • Edmondia
E. crassa (Along with E. crassa var. suborbiculoidea)
E. pitkinensis
  • Leda
L. vaseyana
  • Leiopteria
  • Leptodesma
  • Myalina
M. compressa
M. longicardinalis
N. illinoisensis
  • Parallelodon
  • Pteronites
  • Schizodus (See unidentified section)
S. arkansanus
S. chesterensis
S. depressus
S. insignis
  • Solenomya
  • Sphenotus
S. cherokeense
S. gibsonense
S. quadriplicatum

Scaphopoda, Tusk Shells

Gastropoda, Snails
E. incarinatus
  • Clabrocingulum
  • Gosseletina (See unidentified section)
  • Helcionopsis
H. reticulatus
H. newtonensis
  • Latischisma
  • Leptoptygma (See unidentified section)
  • Microptychis
  • Mourlonia
M. angulata
P. subrotundum
  • Pseudozygopleura
  • Sphaerodoma
S. subcorpulenta
  • Stegocoelia
  • Straparolus
S. planidorsatus
S. triliris
  • Strobeus (See unidentified section)
  • Strophostylus

Cephalopoda
A. furnishi[13]
C. hesperium
C. richardsonianum[13]
C. randolphensis
C. equoyahensis
D. eurekensis
  • Eoasianites
E. globosus
  • Eumorphoceras
E. bisulcatum[13]
  • Metadimorphoceras[13]
  • Mooreoceras
  • Syngastrioceras[13]
  • Trizonoceras[13]

Trilobita
  • Grifithides
G. pustulosus
  • Kaskia
K. chesterensis
K. pitkinensis[14]
P. mucronatus

Ostracoda
  • Glyptopleurain
G. optina
  • Paraparchites
  • Primitia
P. fayettevillensis

Vertebrata

Plantae, Plants

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

A. cordillerensis[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 Leuroceras
  • One species of Dolorthoceras
  • An unnamed shark spine

See also

References
  1. Easton, William H., The Fauna of the Pitkin Formation of Arkansas., Journal of Paleontology: vol. 17:2. March, 1943.
  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.
  3. Adams, G.; Ulrich, E. (1904). "Zinc and lead deposits of northern Arkansas". U.S. Geological Survey Professional Paper. 24: 27, 109.
  4. Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to thefix Paleobiology Database". Retrieved 17 December 2021.
  5. 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.
  6. 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.
  7. Webb, Gregory., 1987., The Coral Fauna of the Pitkin Formation (Chesterian), Northeastern Oklahoma and Northwestern Arkansas. Journal of Paleontology vol. 61:3
  8. Webb., Gregory., 1990., A New Tabulate Coral Species from the Pitkin Formation (Chesterian) of north-central Arkansas. Journal of Paleontology vol. 64:4.
  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.
  10. 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.
  11. 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.
  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.
  13. 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.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.