Oklahoma Highway 18 roadcut, 1.8 miles south of Sulphur (Ordovician of the United States)

Where: Oklahoma (34.5° N, 97.0° W: paleocoordinates 22.2° S, 73.3° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Mountain Lake Member (Bromide Formation), Blackriveran (460.9 - 449.5 Ma)

• member-level stratigraphic resolution

Environment/lithology: marine; gray sandstone and gray shale

• Upper and lower shoreface; transition zone; shallow lagoonal; shallow shelf or carbonate ramp. Environments from M. W. Longman. 1982. Depositional environments. Echinoderm faunas from the Bromide Formation (Middle Ordovician) of Oklahoma: Lawrence, Kansas, University of Kansas Paleontological Institute Monograph 11 : 17-29.
• "[B]asal tan to greenish-gray fine-grained quartz arenite sandstone, with well-rounded and frosted grains, overlain by a sandstone and greenish-gray illitic-chloritic shale above. The sandstone sequence is thickest (more than 37 m) along Lick Creek in the northwestern Arbuckles and thinnest (less than 9 m) in the eastern Arbuckles, losing sand at the top of the section. The overlying shale and limestone is thickest (more than 60 m) along the axis of aulacogen and is mostly shale. In a comparable section in the northeastern Arbuckles, limestone predominates with some sand, and the section is 24 to 31 m thick." Lithology from R, O. Fay and A. A. Graffman. 1982. Stratigraphic studies. Echinoderm faunas from the Bromide Formation (Middle Ordovician) of Oklahoma: Lawrence, Kansas, University of Kansas Paleontological Institute Monograph 11 : 11-16. Edited by J. Sprinkle.

Size class: macrofossils

Reposited in the USNM

Primary reference: G. A. Cooper. 1956. Chazyan and related brachiopods. Smithsonian Miscellaneous Collections 127:1-1245 [P. Wagner/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 164465: authorized by Pete Wagner, entered by Pete Wagner on 02.12.2014

Creative Commons license: CC BY (attribution)

Taxonomic list

Rhynchonellata
 Orthida - Glyptorthidae
Glyptorthis crenulata n. sp. Cooper 1956
Paracrinoidea
 Comarocystitida - Amygdalocystitidae
Oklahomacystis spissus n. sp.2 Frest et al. 1980
 Comarocystitida - Comarocystitidae
Sinclairocystis praedicta n. gen. n. sp.1
Sinclairocystis praedicta n. gen. n. sp.1 Bassler 1950