Silica Formation Units 27-29 (Devonian of the United States)

Where: Ohio (41.7° N, 83.7° W: paleocoordinates 36.4° S, 31.0° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Silica Formation, Givetian (387.7 - 382.7 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: marine; gray, blue, argillaceous limestone and dolomitic, gray, blue, argillaceous limestone

• Overall sequence: Bioclastic limestone; argillaceous limestone; shale. This unit: 27: "limestone, argillaceous, massive, dark blue-gray, some small marcasite concretions"; 28: "limestone, very argillaceous in lower part, less so near top, blue-gray, some small marcasite concretions"; 29: "limestone, very argillaceous, blue-gray, much dolomitized. As much as 3 inches of uppermost part belonging probabl to Ten Mile Creek Dolomite, containing a mixture of Silica species...and Ten Mile Creek well as marcasite concretions"

Primary reference: R. V. Kesling and R. B. Chilman. 1975. Strata and megafossils of the Middle Devonian Silica Formation. University of Michigan Papers on Paleontology 8:1-408 [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 38474: authorized by Michael Foote, entered by Michael Foote on 21.04.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

 Fenestrata -
 Strophomenida - Strophodontidae
"Strophodonta spp." = Strophomena (Strophodonta) Hall 1852
Megastrophia sp. Caster 1939