ammonites
Barwin Quarry (AMNH) (Cretaceous of the United States)

Where: Natrona County, Wyoming (43.2° N, 107.1° W: paleocoordinates 50.0° N, 75.5° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Mesaverde Formation, Judithian (83.5 - 70.6 Ma)

• now dated to upper middle Campanian

• group of beds-level stratigraphic resolution

Environment/lithology: "channel"; lithified, ferruginous, pebbly conglomerate and poorly lithified, yellow, argillaceous sandstone

• "yellowish to golden channel sandstone...richest fossil-bearing level is within a basal ironstone-cemented pebble conglomerate and throughout the overlying 2 m of more friable, yellowish sanstone. Fossils are seen both as isolated occurrences in massively cross-bedded sandstones and within concentrations of clay-gall stringers along thin bedding planes."

Size class: mesofossils

Collected by M. McKenna in 1961, 1966, 1970; reposited in the AMNH

Collection methods: bulk, sieve,

• collected 1961, 1966, 1970

Primary reference: J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 [J. Alroy/J. Alroy/J. Alroy] more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 14433: authorized by John Alroy, entered by John Alroy on 30.04.1994, edited by Matt Carrano

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)