ammonites
Fossil Brook Member - Ratcliffe Brook, New Brunswick (Cambrian of Canada)

Also known as Ratcliffe Brook (RBr)

Where: New Brunswick, Canada (45.4° N, 65.8° W: paleocoordinates 69.5° S, 64.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Fossil Brook Member (Chamberlain's Brook Formation), St Davids (513.0 - 501.0 Ma)

• AGE: Acadian series. Correlated with the bae of the Caesaraugustian Stage in Spain and middle of the Toushamian Stage in Morocco, and can be informally regarded as indicating an interval in the transition from the lower Middle to middle Middle Cambrian. Assigned to St Davids stage based on correlation with age range of Acadian.

•

•SPECIFIC COMMENTS: Lower Fossil Brook Member.

•

•GENERAL COMMENTS: Thin (up to 14m thick) distinctive unit, unconformity bound depositional sequence. It forms the top of the green, pruple, and red siliciclastic mudstone-dominated Chambelain's Brook Formation (lower Middle Cambrian, up to 160m thick) and underlies the dark gray and bvlack mudstone-dominated Manuels River Formation (middle Middle Cambrian, up to 60m thick).

• group of beds-level stratigraphic resolution

Environment/lithology: marine; concretionary, shelly/skeletal, gray, green mudstone

• Significant basin reorganization in the transtensional tectonic regime of the Avalon continent controlled regional onlap and deposition, lateral facies changes, and the regular appearance of trilobite-rich limesones (otherwise rare lower in the Chambelain's Brook Formation), and development of the erosive lower and upper contacts of the Fossil Brook Member.
• Green-gray siliciclastic mudstone with carbonate nodules.

Size class: macrofossils

Collection methods: surface (float), surface (in situ),

• Collected by Kim, Westrop and Landing; supplemented with collections from PRI, ROM, and New York State Museum; material reposited at ROM, New Brunswick Museum (NBMG) and New York State Museum.

Primary reference: D. H. Kim, S.R. Westrop, and E. Landing. 2002. Middle Cambrian (Acadian series) conocoryphid and paradoxidid trilobites from the upper Chamberlain's Brook Formation, Newfoundland and New Brunswick. Journal of Paleontology 76(5):822-842 [A. Miller/A. Hendy/A. Hendy] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 49061: authorized by Austin Hendy, entered by Austin Hendy on 07.04.2005

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)