During the Mississippian rocks of the Chainman Shale were deposited in the Antler Foreland Basin. Fossil cephalopods are very common in these rocks in west-central Utah and eastern Nevada. Asbian age members of the Chainman Shale include the Skunk Spring Limestone Bed and the lowest beds of the Camp Canyon Member. The fossil cephalopods shown below are from these rocks in the Confusion Range of Millard and Juab Counties.
References: Gordon, Mackenzie, Jr., 1971, Goniatites
n.sp., A Late Meramec (Mississippian) Index Fossil,
U.S.G.S. Professional Paper 750-C; Kullman, J., Korn, D., and Petersen,
M. S., 2000, GONIAT
Database System, version 2.90, Tubingen; Korn, D. & Titus, A.L.,
2011, Goniatites Zone (middle Mississippian) ammonoids of the Antler
Foreland Basin (Nevada, Utah). Bulletin of Geosciences 86 (1), 107–196.
Kazakhoceras bylundi Korn and Titus 2011
Dimorphoceras rileyi Korn and Titus 2011
acus Korn and Titus 2011.
Goniatites deceptus Zone
Concretion containing Goniatites deceptus Korn and Titus
2011 and an orthocone
gordoni Korn and Titus 2011