Santonian age cephalopods occur in the Emery Sandstone Member of the Mancos Shale. The Garley Canyon Beds and the Lower Emery Beds south from Huntington are where the fossils pictured below were found. These rocks were deposited in the Sevier Foreland Basin.
References: Reeside,
J. B., Jr., 1927, The Cephalopods of the Eagle Sandstone and Related
Formations in the Western Interior of the United States, U.S.G.S.
Professional Paper 151; Cobban, W. A.,
1951, Scaphitoid Cephalopods of the Colorado Group, U.S.G.S.
Professional Paper 239; Cobban, W. A., 1976, Ammonite
Record from the Mancos Shale of the Castle Valley-Price-Woodside Area,
East-Central Utah, B.Y.U. Geology Studies Vol.22, Pt.3.
A large Placenticeras
pseudocostatum
(Johnson) 1903, at
the outcrop
Clioscaphites vermiformis (Meek
& Hayden) 1862
Baculites codyensis Reeside 1927
Texanites ?texanus (Roemer)
1852
217mm dia.
Typical fossil cephalopods from the Lower
Emery Sandstone
and Garley Canyon Beds
Placenticeras pseudocostatum (Johnson)
1903,
is
the common ammonite
Clioscaphites vermiformis (Meek
& Hayden) 1862, Top Center, Eutrephoceras alcesense
Reeside
1927, Bottom Center
Baculites codyensis Reeside 1927,
Lower Left.