ammonites
Pierre Shale (USGS D1927, D1929) (Cretaceous of the United States)

Where: Niobrara County, Wyoming (43.3° N, 104.3° W: paleocoordinates 49.4° N, 72.4° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Lower unnamed shale Member (Pierre Shale Formation), Campanian (83.5 - 70.6 Ma)

• bed-level stratigraphic resolution

Environment/lithology: offshore; lithified, concretionary, brown, gray, silty, calcareous shale

• "shale; weathering med. gray; lower 17 ft silty; contains brown weathering ls concretions at 50 and 58 ft above base and rarely a ls concretion nearer base."
• "shale; weathering med. gray; lower 17 ft silty; contains brown weathering ls concretions at 50 and 58 ft above base and rarely a ls concretion nearer base."

Reposited in the USGS

Collection methods: mechanical,

• "[collected] from concretions 50 ft above base"

Primary reference: J. R. Gill, W. A. Cobban, and P. M. Kier. 1966. The Red Bird Section of the Upper Cretaceous Pierre Shale in Wyoming. United States Geological Survey Professional Paper 393-A:1-73 [J. Alroy/M. Sommers/A. Clement] more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 1655: authorized by John Alroy, entered by Mike Sommers on 25.05.1999

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