USGS D1545, Morrison (Cretaceous of the United States)

Where: Jefferson County, Colorado (39.6° N, 105.1° W: paleocoordinates 46.3° N, 81.4° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Hoploscaphites birkelundae ammonoid zone, Pierre Shale Formation, Late/Upper Maastrichtian (70.6 - 66.0 Ma)

• Base of the upper transition member of the Pierre Shale

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified shale

Size class: macrofossils

Reposited in the USNM

Primary reference: N. H. Landman and W. A. Cobban. 2003. Ammonites from the upper part of the Pierre Shale and Fox Hills Formation of Colorado. American Museum Novitates 3388:1-45 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 178284: authorized by Matthew Clapham, entered by Matthew Clapham on 29.04.2016

Creative Commons license: CC BY (attribution)

Taxonomic list

Cephalopoda
 Ammonitida - Sphenodiscidae
Coahuilites sheltoni Böse 1928 ammonite