ammonites
USGS 7789-CO. I-64 east of bridge over Kentucky River (Ordovician of the United States)

Where: Franklin County, Kentucky (38.2° N, 84.8° W: paleocoordinates 27.1° S, 63.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

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

• Section no. 86; "Upper part of Devils Hollow Member, Lexington Limestone."

• group of beds-level stratigraphic resolution

Environment/lithology: lagoonal or restricted shallow subtidal; lithified, coarse-grained, shelly/skeletal limestone and lithified limestone

• "The Devils Hollow Member seems to represent very shallow subtidal to intertidal environments of deposition, because sedimentary structures characteristic of tidal flats (that is, mud cracks, intraformational breccia) are not present in the micritic limestones.... these beds were deposited in shallow restricted lagoons of higher than normal salinity. The gastropod coquinas were bar and (or) beach deposits directly associated with these lagoons."
• "type locality ... 15 ft of coarse-grained, gastropod coquina overlain by 10 ft of micritic limestone containing ostracodes (resembling the Tyrone Limestone). These two types of rock intertongue, and at some localities only one of the two types is present.... The gastropod coquina is a coarse biosparite crowded with specimens.... Locally the coquina may be composed of brachiopods rather than gastropods; in either instance, the fossils may be silicified. The micritic limestone contains only ostracodes and sparse gastropods and pelecypods, which may be silicified."

Size class: macrofossils

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 101380: authorized by Pete Wagner, entered by Hallie Street on 21.12.2010