USGS 4346-CO - Hillard Limestone, Montauk Bluff area (Cambrian of the United States)

Also known as 63ABa3373

Where: Alaska (65.0° N, 141.0° W: paleocoordinates 5.0° N, 63.0° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Hillard Limestone Formation, Middle Cambrian (509.0 - 497.0 Ma)

• STRATIGRAPHIC RELATIONS: From Hillard Limestone, which regionally overlies the Early Cambrian Adams Argillite and is unconformably overlain by the lower part of the Rhoad River Formation. AGE: lower Middle Cambrian based on K. serrata which is conspecific with P. atavus. STRATIGRAPHIC POSITION: 20 ft stratigraphically above the lowest exposure of Hillard Limestone.

• bed-level stratigraphic resolution

Environment/lithology: lithified, medium-grained limestone

• ENVIRONMENT: Carbonate deposition, intermittent turbulent conditions.
• SPECIFIC LITHOLOGY: Fossils from bed of medium-grained limestone. LITHIFICATION: Lithified, based on age and facies.

Size class: macrofossils

Reposited in the USNM

• COLLECTOR: A.R. Palmer and E.E. Brabb (1963). REPOSITORY: USGS and USNM.

Primary reference: A.R. Palmer. 1968. Cambrian trilobites of East-Central Alaska. United States Geological Survey Professional Paper 559(B) [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 64766: authorized by Austin Hendy, entered by Austin Hendy on 14.09.2006

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Only trilobites (following monograph focus). No other taxa listed. IDENTIFIER: A.R. Allison. NOMENCLATURE: Authoritative publication, though probably somewhat age nomeclature, with species designations.
Show authors, comments, and common names
Trilobita
 Corynexochida - Corynexochidae
Corynexochidae indet.
Corynexochidae indet. Angelin 1854 trilobite
Artiopoda
 Agnostida - Ptychagnostidae
Ptychagnostus sp.
Ptychagnostus sp. Jaekel 1909
 Agnostida - Spinagnostidae
cf. Cotalagnostus lens
cf. Cotalagnostus lens Grönwall 1902
Subspecies: C. lens claudicans