East line of P. L. Reinhardt Tract (Eocene of the United States)

Also known as M 576

Where: Leon County, Texas (31.2° N, 95.9° W: paleocoordinates 33.1° N, 84.8° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Wheelock Member (Crockett Formation), Lutetian (47.8 - 41.3 Ma)

• Upper Claiborne Group, Cook Mt. Fm. (now assigned to Crockett Formation), Wheelock Member, basal conglomerate. Calcareous nannoplankton indicates an age of biochronozone NP16 (Yancey and Davidoff, 1991, p. 80) and planktic foraminifers indicate deposition during the Morozovella lehneri (P12) or Orbulinoides beckmanni (P13) zones (Gaskell, 1989). A 25 cm thick volcanic ash bed present in overlying strata of the Crockett Formation, about 15 m above the Moseley bed (Kersey and Stanton, 1979), has an 40Ar/39Ar radiometric date of 41.841 ± 0.016 Ma (Heintz et al., 2015). The ash-bearing strata are further corroborated as upper part of biochronozone NP16 by Marie-Pierre Aubry (2002, unpublished report) and the upper part of biochronozone P12 (= E10–E11 biochronozones) by W. A. Berggren (2004, unpublished report), based on an overlap of Acarinina bullbrooki and Turborotalia pomeroli. Therefore, late Lutetian in age.

• group of beds-level stratigraphic resolution

Environment/lithology: transition zone or lower shoreface; lithified conglomerate

• Yancey (1995): The Moseley bed is an amalgamated storm unit with a hardground horizon at the top of the main body portion. The hardground horizon is developed on a zone of clasts. Although this was originally identified as a conglomerate (Stenzel; 1936; Stenzel et al., 1957) that supposedly indicated the presence of a regional erosional unconformity, it developed in a submarine environment. The clasts consist of spherical concretions, formed of cemented shelly sand of the same lithology as the underlying sediment in the main body of the Moseley bed. There are also a few dark, fine-grained concretions of cemented mudstone. The clasts occur in a lag deposit concentrated from underlying sediment, showing that the Moseley deposit was relatively unconsolidated at the time of concentration.

Size class: mesofossils

Primary reference: K. V. Palmer and D. C. Brann. 1965. Catalogue of the Paleocene and Eocene mollusca of the southern and eastern United States. Part 1. Pelecypoda, Amphineura, Peteropoda, Scaphopoda and Cephalopoda. Bulletins of American Paleontology 48:1-471 [M. Kosnik/M. Kosnik/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 98895: authorized by Jocelyn Sessa, entered by Ursula Smith on 22.10.2010

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Cephalopoda
 Nautilida - Nautilidae
Eutrephoceras reesidei
Eutrephoceras reesidei Stenzel 1940 nautiloid