Head of Bear Creek (Cretaceous) (Cretaceous to of the United States)

Where: Pennington County, South Dakota (43.9° N, 102.6° W: paleocoordinates 49.8° N, 71.8° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Campanian to Campanian (83.6 - 66.0 Ma)

• concretions found "about thirty feet above the undoubted base of the White River beds" thought to be reworked from the "Ft. Pierre" (= Pierre Shale; Campanian or Maastrichtian based on ammonites)

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified, concretionary siliciclastic sediments

• "concretions... stained with haematite on the outside and wherever weathered" and "from one to three feet in diameter"

Size class: macrofossils

Collected in 1903

• Amherst College collection

Primary reference: F. B. Loomis. 1904. Two new river reptiles from the Titanothere beds. American Journal of Science 18:427-432 [J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 99710: authorized by John Alroy, entered by John Alroy on 19.11.2010

Creative Commons license: CC BY (attribution)

Taxonomic list

Cephalopoda
 Ammonitida - Baculitidae
Baculites ovatus Say 1820 ammonite
Reptilia
 Squamata - Mosasauridae
? Platecarpus sp. Cope 1869 mosasaur
"Platycarpus ?"