Middle Cambrian linguliformean brachiopods of the Pika and Sullivan formations, southern Canadian Rocky Mountains, Alberta, Canada

Linguliformean brachiopods were collected and described from the middle Cambrian Pika and Sullivan formations in the southern Canadian Rocky Mountains. These formations consist of coarse-grained grainstone interbedded with lime mudstones and siltstones in a storm-influenced, distal offshore setting. Grainstone and rudstone beds record high-energy events such as storms and tsunamis. Brachiopods occur mostly in the grainstone interbeds along with disarticulated trilobite sclerites and eocrinoid ossicles, all of which likely did not experience long-distance transport. Breakage of brachiopod valves is common in grainstone and is also observed alongside rare abrasion in lime mudstone, suggesting occasional bottom turbulence. Only rare specimens of the paterinid Micromitra Meek 1873 sp. indet. were found in the Bolaspidella trilobite Biozone (Drumian Stage) of the Pika Formation. The assemblage from the Cedaria trilobite Biozone (Guzhangian Stage) of the Sullivan Formation includes the obolids Dicellomus politus Hall 1871, D. cf. D. amblia Bell 1944, D. appalachia Walcott 1905, and D. nanus Meek and Hayden 1862. No acrotretids were recovered. This low-diversity fauna could reflect the deeper water and more outboard depositional setting of the Sullivan Formation in comparison to other contemporaneous units elsewhere. Brachiopods recovered from the Sullivan Formation at Mount Murchison, the most seaward locality, show a wider range of sizes by comparison to those from Windy Point, except for those belonging to D. politus. This suggests that the sorting of the valves at Mount Murchison was not as significantly affected by environmental factors such as intensity of high-energy events.

Name thesis:degree_name

Master of Science (M.Sc.)

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Geology

Grantor

University of Saskatchewan

Year dc:date.issued

2025

Author dc:creator

• Kline, Amy Marie

Advisors dc:contributor.advisor

• Sproat, Colin D
• Pratt, Brian R

Committee members dc:contributor.committeemember

• Buatois, Luis A
• Aitken, Alec E
• Mangano, Gabriela M

• brachiopod
• Guzhangian
• Drumian
• Obolidae
• Dicellomus
• paleoecology
• paleontology

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10388/16976

OAI identifier oai:identifier

oai:harvest.usask.ca:10388/16976