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HB 113 Southern Tobin Range (Triassic to of the United States)

Where: Pershing County, Nevada (40.2° N, 117.6° W: paleocoordinates 9.5° N, 42.3° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Fossil Hill Member (Favret Formation), Anisian to Anisian (247.2 - 235.0 Ma)

• "The base of the Fossil Hill varies in age (early Early Anisian to early Late Anisian) because of synsedimentary block faulting. Where no significant disconformity occurs at its top, its upper limit consistently has an early Ladinian age."

• bed-level stratigraphic resolution

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

• "The Fossil Hill Member is the laterally most extensive rock unit of the Star Peak basin, and blanketed an area exceeding 5,000 km2. It consists mainly of thin-bedded black micritic limestones alternating with silty shales. Deposition below wave base and anoxic bottom waters are typical traits of the Fossil Hill. This is strongly supported by the nearly exclusive occurrence of planktonic, pseudoplanktonic, and nektonic organisms as well as abundant hydrocarbon residue (Nichols and Silberling, 1977)."

Size class: macrofossils

Collected in 1991; reposited in the FMNH

Primary reference: H. Bucher. 1988. A new Middle Anisian (Middle Triassic) ammonoid zone from northwestern Nevada. Eclogae Geologicae Helvetiae 81(3):723-762 [M. Clapham/M. Clapham/M. Clapham] more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 107740: authorized by Matthew Clapham, entered by Matthew Clapham on 14.04.2011

Creative Commons license: CC BY (attribution)