Offshore zone -7, Kensington Quadrangle, Mill Creek (Ordovician of the United States)

Where: Walker County, Georgia (34.8° N, 85.4° W: paleocoordinates 29.2° S, 66.2° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Caradoc (458.4 - 449.5 Ma)

• No information given

Environment/lithology: offshore; brown, gray, argillaceous, silty limestone and red, yellow, calcareous siltstone

• There are three units; unit one and unit two are fossiliferous, while unit 3 is less so. Unit one consists of yellowish-gray to brownish-gray argillaceous limestone, some silty limestone, typically thinly bedded and often weathering to blue-gray. Dark gray to black calcilutite is present in some localities. Unit two consists of thin, calcarous siltstones to silty limestones, ranging in color from red to brownish-red, greenish-yellow, and tan. Unit three consists of silty limestone or limy mudstone, blue, red, yellow, or gray in color; thinly to thickly bedded.

Size class: macrofossils

Primary reference: A. T. Allen and J. G. Lester. 1957. Zonation of the Middle and Upper Ordovician strata in northwestern Georgia. Georgia State Division of Conservation, the Geological Survey Bulletin 66:1-104 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 33104: authorized by Steven Holland, entered by Tori Hanson on 22.07.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
unclassified
  -
Hemiphragmus imperfectus, Idiostrophis sp., Rostricella plena
Strophomenata
 Strophomenida - Furcitellidae
"Rafinesquina minnesotensis" = Oepikina minnesotensis
"Rafinesquina minnesotensis" = Oepikina minnesotensis Winchell 1881
 Strophomenida - Strophomenidae
Strophomena sp., Strophomena planumbona
Strophomena sp. Rafinesque and De Blainville 1824
Rhynchonellata
 Atrypida - Cyclospiridae
Cyclospira sp.
Cyclospira sp. Hall and Clarke 1893
 Orthida - Dalmanellidae
"Resserella rogata" = Paucicrura rogata, Resserella sp.
"Resserella rogata" = Paucicrura rogata Sardeson 1892
(Sanderson)
Resserella sp. Bancroft 1928
 Orthida - Glyptorthidae
Glyptorthis insculpta
Glyptorthis insculpta Hall 1847
(Hall)
 Orthida - Hesperorthidae
Hesperorthis sp.
Hesperorthis sp. Schuchert and Cooper 1931
 Orthida - Plectorthidae
Desmorthis nevadensis, Doleroides gibbosus, Mimella melonica
Desmorthis nevadensis Ulrich and Cooper 1936
Ulrich & Cooper
Doleroides gibbosus
(Billings)
Chileata
 Dictyonellida - Eichwaldiidae
Dictyonella reticulata
Dictyonella reticulata Hall 1868
(Hall)
Stenolaemata
 Trepostomida -
Nicholsonella sp.
Nicholsonella sp. Ulrich 1890
 Cryptostomata - Arthrostylidae
Helopora spiniformis
 Trepostomata - Heterotrypidae
Dekayella praenuntia
Dekayella praenuntia Ulrich 1893
Ulrich
Cephalopoda
 Actinocerida - Gonioceratidae
Gonioceras anceps
Gonioceras anceps Hall 1847
Hall
 Orthocerida - Orthoceratidae
Michelinoceras sociale
Gastropoda
 Euomphalina - Macluritidae
Maclurites sp.
Maclurites sp. Le Sueur 1818 snail
 Euomphalina - Ophiletidae
"Ophileta levata" = Ophileta laevata
"Ophileta levata" = Ophileta laevata Vanuxem 1842 snail
(Vanuxem)
 Murchisoniina - Eotomariidae
Liospira vitruvia
Liospira vitruvia Billings 1865 snail
Billings
Ostracoda
 Leperditicopida - Leperditiidae
Leperditia cf. fabulites
Leperditia cf. fabulites ostracod
(Conrad)
Rhodophyceae
  - Solenoporaceae
Solenopora compacta
Tetradium
  -
Tetradium sp., Tetradium syringoporoides
Tetradium sp. Dana 1846