USGS D920-CO (Ordovician to of the United States)

Where: Inyo County, California (37.0° N, 118.1° W: paleocoordinates 3.7° S, 89.2° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Al Rose Formation, Stairsian to Stairsian (485.4 - 471.8 Ma)

• Graptolites and trilobites have been collected from several localities, mostly near the top of the formation in unit 3.

Environment/lithology: marine; lithology not reported

• This collection contained two rock types: a fine-grained gray limestone without identifiable trilobites, and a white limestone with abundant trilobite hash. This latter sample was dissolved in formic acid and yielded a thoroughly deformed suite of small silicified (? )trilobites, indeterminate acrotretid brachiopods, and echinoderm parts.

Size classes: mesofossils, microfossils

Preservation: replaced with silica

Reposited in the USGS

Primary reference: D. C. Ross. 1966. Stratigraphy of some Paleozoic formations in the Independence quadrangle, Inyo County, California. United States Geological Survey Professional Paper 396:1-64 [J. Marcot/J. Marcot]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 196128: authorized by Jonathan Marcot, entered by Jonathan Marcot on 05.09.2018

Creative Commons license: CC BY (attribution)

Taxonomic list

Trilobita
 Asaphida - Asaphidae
? Trigonocerca sp. Ross 1951 trilobite
"Trigonocercal sp. (a large pygidium)"