Where: Alberta, Canada (53.2° N, 119.1° W: paleocoordinates 3.2° S, 79.4° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Bonnia-Olenellus trilobite zone, Mural Formation, Dyeran (515.3 - 511.2 Ma)

• Trilobites from below the upper Nevadella Zone and lower Bonnia-Olenellus boundary were found to have a restricted diversity, while those above are markedly different and exhibit diverse forms. The possible cause is a disconformity or a disconformity with an erosionally-erased biomere boundary. The boundary between the Nevadella and Bonnia-Olenellus zones is within the interval 14.2m to 14.5m above the base of the middle mudstone member. NOTE: The Tah Formation has been renamed the Mural Formation by Burling. AGE: Waucoban; refined by A. Hendy (6/2009) on the basis of biostratigraphic data (= Bonnia-Olenellus zone).

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified siltstone

Size classes: macrofossils, mesofossils

Collection methods: Lithology and age of the sections were restudied by Fritz and Mountjoy in 1975 and additional collecting by Fritz and Mountjoy in 1971 and 1973 at Mumm Peak, Cinnamon Peak-Whitehorn Mountain, and Walcott's nearby sections are integrated into the study.

Primary reference: W. H. Fritz. 1992. Walcott's Lower Cambrian Olenellid trilobite collection 61k, Mount Robson Area, Canadian Rocky Mountains. Geological Survey of Canada Bulletin 432 (432)1-66 [M. Patzkowsky/P. Borkow/P. Borkow]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 10877: authorized by Mark Patzkowsky, entered by Phil Borkow on 29.06.2001

Creative Commons license: CC BY (attribution)