Where: Routt County, Colorado (40.1° N, 106.9° W: paleocoordinates 41.0° N, 101.8° W)

• coordinate based on political unit

When: Split Rock Formation, Chattian to Chattian (28.1 - 20.4 Ma)

• "Arikaree-like sandstone near Yampa" dated at 23.5 +/- 2.5 Ma FTz

•formation and county follow Rich 1981

Environment/lithology: terrestrial; lithology not reported

Size class: macrofossils

Primary reference: G. A. Izett. 1975. Late Cenozoic sedimentation and deformation in northern Colorado and adjoining areas. Geological Society of America Memoir 144:179-209 [J. Alroy/J. Alroy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 19128: authorized by John Alroy, entered by John Alroy on 27.07.1994

Creative Commons license: CC BY (attribution)