Marjum Formation, Bed: 614M609 (Cambrian of the United States)

Where: Utah (39.0° N, 113.0° W: paleocoordinates 4.5° S, 92.1° W)

• coordinate estimated from map

• hand sample-level geographic resolution

When: Unit 14 Member (Marjum Formation), Middle Cambrian (509.0 - 497.0 Ma)

• Listed as Upper-Middle Cambrian. Bolaspidella zone, Bolaspidella contracta subzone; sampled only the deeper portions

• group of beds-level stratigraphic resolution

Environment/lithology: slope; poorly lithified, fine-grained, flat-pebble, silty limestone and poorly lithified shale

• Listed as Upper Slope. Outer detrital belt; three facies listed indiscriminately: (1) Thin-bedded, platy, fine-grained, dark gray to black, calcareous siltstone or silty limestone; (2) thin-bedded, fine-grained, dark gray to black, argillaceous limestone with light-yellow to dark brown silty partings; and (3) laminated siltstone, mudstone, and claystone of various shades of yellow, brown, or gray
• 60% thin-bedded, fine-grained, silty limestone and 38% shale and mudstone with a few beds of flat-pebble conglomerate and thin algal biostromes

Size classes: macrofossils, mesofossils

Primary reference: R. A. Robison. 1964. Upper Middle Cambrian stratigraphy of western Utah. Geological Society America Bulletin 75:995-1010 [P. Novack-Gottshall/P. Hearn/P. Hearn]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 77278: authorized by Phil Novack-Gottshall, entered by Paul Hearn on 08.01.2008

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Lingulata
 Acrotretida - Acrotretidae
"Pegmatreta bellatula" = Linnarssonia
"Pegmatreta bellatula" = Linnarssonia
"Abundant to rare"
Trilobita
 Ptychopariida - Lonchocephalidae
Trymataspis depressa
Trymataspis depressa Robinson 1964 trilobite
"One cranidium"