USGS locality 331 near Sedalia, CO Dawson arkose (Paleocene of the United States)

Also known as USGS locality 331

Where: Colorado (39.4° N, 103.0° W: paleocoordinates 44.8° N, 82.7° W)

• coordinate based on political unit

When: Dawson arkose Formation, Paleocene (66.0 - 56.0 Ma)

• Denver Basin

• formation-level stratigraphic resolution

Environment/lithology: fluvial; shale and sandy claystone

• 'Dawson arkose: arenaceous clays, shales, coals, rhyolite flows'

Reposited in the USNM

Collection methods: quarrying, mechanical,

• Specimens were collected by A. Lakes, and given to S. F. Emmons, USGS, who gave them to Brown.

Primary reference: R. W. Brown. 1962. Paleocene flora of the Rocky Mountains and Great Plains. United States Geological Survey Professional Paper 375:1-119 [P. Wilf/J. Sessa/J. Sessa]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 40057: authorized by Peter Wilf, entered by Jocelyn Sessa on 16.06.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Species lists for Brown 1962 were compiled from the publication and provided for the Paleobiology Database by Drs. Steven R. Manchester and Peter R. Crane.
 Rhamnales - Rosidae