USGS DR 2487, De Long Mountains [Otuk Fm] (Triassic of the United States)

Also known as KE98-28; Loc. 66

Where: Alaska (68.2° N, 162.8° W: paleocoordinates 59.5° N, 43.7° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Otuk Formation (Etivluk Group), Norian (228.0 - 208.5 Ma)

• STRATIGRAPHIC RELATIONS: From the Otuk Formation of the Etivluk Gp. AGE: Conodonts from this locality indicate late Middle-Late Triassic, but radiolarians restrict age to middle Late Triassic (late middle-early late Norian). Radiolarian fauna assignable to the Betraccium Zone (Pantanellium silberlingi Subzone) of Pessagno and others (1979) and Blome and others (1988). STRATIGRAPHIC POSITION: Sample from unknown position within the Etivluk Group (Otuk Formation).

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified chert and lithified dolomite

• SPECIFIC LITHOLOGY: Chert interbedded with very fine grained dolostone. LITHIFICATION: Lithified, on the basis of facies description and preparation techniques.

Size class: macrofossils

Collected by Dumoulin in 2000; reposited in the USNM

• COLLECTOR: J. A. Dumoulin. REPOSITORY: Presumably USNM.

Primary reference: J. A. Dumoulin, A. G. Harris, C. D. Blome and L. E. Young. 2006. Conodont and radiolarian data from the De Long Mountains Quadrangle and adjacent areas, northern Alaska. United States Geological Survey Open-File Report 2006(106):1-174 [A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 91033: authorized by Austin Hendy, entered by Austin Hendy on 01.09.2009

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for radiolarians, possibly including conodonts and other macrofossils. NOMENCLATURE: Identified by C. D. Blome; not an authoritative publication, but with modern nomenclature and species-resolution identifications.
Show authors, comments, and common names
Protozoa
 Entactinaria - Saturnalidae
Pseudoheliodiscus viejoensis
Pseudoheliodiscus viejoensis Pessagno et al. 1979 radiolarian
 Spumellaria - Pantanelliidae
Betraccium sp.
Betraccium sp. Pessagno et al. 1979 radiolarian
 Spumellaria - Capnuchosphaeridae
Capnuchosphaera aff. theoloides, Capnuchosphaera mexicana, Capnuchosphaera smithorum, Capnuchosphaera aff. lenticulata, Capnuchosphaera schenki, Sarla vetusta
Capnuchosphaera mexicana Pessagno et al. 1979 radiolarian
Capnuchosphaera smithorum Blome 1983 radiolarian
Capnuchosphaera aff. lenticulata Pessagno et al. 1979 radiolarian
Capnuchosphaera schenki Blome 1983 radiolarian
Sarla vetusta Pessagno et al. 1979 radiolarian