Unit 10, Clark County [Pioche Shale Fm] (Cambrian of the United States)

Where: Clark County, Nevada (39.6° N, 119.5° W: paleocoordinates 0.1° S, 92.8° W)

• coordinate estimated from map

When: Pioche Shale Formation, Dyeran (516.0 - 513.0 Ma)

• 5 feet thick. AGE: Dyeran; refined by A. Hendy (6/2009) on the basis of biostratigraphic data.

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified sandstone and lithified sandstone

• Sandstone, interstratified, very fine-grained beds; 10% grey sandy shale; 20% dark grey shaley sandstone; 30% green shaley sandstone; 40 % hard brown sandstone all in lenses and thin strata.

Size class: macrofossils

Preservation: cast

Collection methods: Contains abundant trilobites and worm casts. Annelids not identified.

Primary reference: P. D. Pack and H. B. Gayle. 1971. A new Olenellid trilobite, Biceratops nevadensis, from the Lower Cambrian near Las Vegas, Nevada. Journal of Paleontology 45(5):893-898 [M. Patzkowsky/P. Borkow/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 9622: authorized by Mark Patzkowsky, entered by Phil Borkow on 23.03.2001

Creative Commons license: CC BY (attribution)

Taxonomic list

 Redlichiida - Olenellidae
"Paedumias sp." = Paedeumias, Biceratops nevadensis, "Fremontia sp." = Mesonacis
"Paedumias sp." = Paedeumias Walcott 1910 trilobite
Biceratops nevadensis Pack and Gayle 1971 trilobite
"Fremontia sp." = Mesonacis Walcott 1885 trilobite
Annelida indet. Lamarck 1809