Gateway to the Paleobiology Database
Medicine Pole Hills (Eocene of the United States)

Also known as PTRM V89002

Where: Bowman County, North Dakota (46.1° N, 103.3° W: paleocoordinates 47.4° N, 94.2° W)

• coordinate based on political unit

• outcrop-level geographic resolution

When: Chalky Buttes Member (Chadron Formation), Chadronian (37.2 - 33.9 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: "channel"; poorly lithified, fine-grained, medium, brown sandstone

• "characteristic of the distal reaches of some modern braided rivers... braidbelt environment" (Smith 2006)
• "brownish, poorly sorted, poorly consolidated, generally medium- to fine-grained sandstone... 2.5 m local section... two trough cross-bedded units (units 2 and 6); unit 5 [and] 2 [are] indistinguishable... Along the bedding planes are strewn gray mudballs... Unit 3 is a fine-grained, parallel-bedded sandstone. Unit 4 displays planar cross-bedding." (Smith 2006)

Size classes: macrofossils, mesofossils

Collection methods: bulk, sieve,

• "All fossils were collected... by dry-screening quarried sediment" (Smith 2006)

Primary reference: D. A. Pearson and J. W. Hoganson. 1995. Proceedings of the North Dakota Academy of Sciences 49 [J. Alroy/J. Alroy] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 16991: authorized by John Alroy, entered by John Alroy on 12.04.1997, edited by Torsten Liebrecht, Clint Boyd and Terri Cleary

Creative Commons license: CC BY (attribution)