ammonites
USGS 7796-CO. I-75, south of Route 418 (Ordovician of the United States)

Where: Fayette County, Kentucky (37.9° N, 84.4° W: paleocoordinates 27.5° S, 63.1° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Belodina confluens conodont zone, Tanglewood Limestone Member (Lexington Limestone Formation), Shermanian (460.9 - 449.5 Ma)

• "3-9 ft above base of Cane Run Bed, Grier Limestone Member, Lexington Limestone."; "Lowermost tongue of Tanglewood Limestone Member, Lexington Limestone, below Brannon Member, Lexington Limestone."

• bed-level stratigraphic resolution

Environment/lithology: sand shoal; lithified, medium-grained, phosphatic, gray, calcareous limestone

• "interpreted the Tanglewood calcarenite body as a bank that stood above surrounding areas of the sea floor, with tidal currents producing migrating sandbars."
• "The Tanglewood Limestone Member is an extensive irregular body of bioclastic calcarenite that completely intertongues with other members of the upper Lexington Limestone and the Clays Ferry Formation. It is typically a crossbedded, phosphatic, pinkish-gray, medium-grained, well-sorted, bioclastic calcarenite in which whole fossils or large fossils fragments are rather uncommon. The unit ranges in thickness from 60 to 100 ft, the variation due to intertonguing with other members. The calcarenite consists largely of bryozoan, brachiopod, and crinoid fragments that are thought to have been transported from adjacent sites of accumulation of the Grier Limestone and Millersburg Members."

Size classes: macrofossils, mesofossils

Preservation: replaced with silica

Reposited in the USNM

Primary reference: G.P. Wahlman. 1992. Middle and Upper Ordovician symmetrical univalved molluscs (Monoplacophora and Bellerophontina) of the Cincinnati Arch region. United States Geological Survey Professional Paper 1066(O):1-123 [P. Wagner/P. Wagner/P. Wagner] more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 101401: authorized by Pete Wagner, entered by Hallie Street on 22.12.2010