Webster Unit 31A, Bird Spring Fm. (Carboniferous of the United States)

Where: Clark County, Nevada (36.7° N, 114.8° W: paleocoordinates 1.8° N, 44.9° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Bird Spring Formation, Bashkirian (323.2 - 315.2 Ma)

• Morrowan is equivalent to Bashkirian at Arrow Canyon according to Bishop et al., 2009 (Palaeogeography, Palaeoclimatology, Palaeoecology 276:217–243)

• bed-level stratigraphic resolution

Environment/lithology: shallow subtidal; lithified, massive, gray, sandy limestone

• Sandy limestone, light grey, weathers rust brown, massive, silicified cross-bedding approximately 0.3m high by 1m long.

Size class: macrofossils

Preservation: replaced with silica

Collection methods: bulk, chemical

Primary reference: D. W. Petersen and R. L. Langenheim, Jr. 1984. Spiriferellina lata Lane in the Uppermost Chesterian in the Bird Spring Group at Arrow Canyon, Clark County, Nevada. Transactions of the Illinois Academy of Sciences 77(3 and 4):207-218 [N. Bonuso/P. Monarrez]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 141793: authorized by Nicole Bonuso, entered by Pedro Monarrez on 01.04.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

 Spiriferinida - Spiriferellinidae