Troitsa Ridge, Smithers Formation, level Tr 11 (Jurassic of Canada)

Where: British Columbia, Canada (53.6° N, 127.1° W: paleocoordinates 36.7° N, 69.7° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Smithers Formation (Hazelton Group), Aalenian (174.1 - 170.3 Ma)

• late Aalenian, approx. 112 m from bottom of section

• bed-level stratigraphic resolution

Environment/lithology: marine; tuffaceous shale and shelly/skeletal, sandy siltstone

• minor felsic volcanic units interbedded in a predominantly sedimentary sequence. fossils collected from an 8 m thick soft, well-bedded, felsic, waterlain crystal-lithic tuff interbedded with brown, fossiliferous siltstone and fine-grained sandstone (this unit is well above the 8 m fossiliferous section described, but appears to be same rock typ on the strat column)

Size class: macrofossils

Primary reference: J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 37622: authorized by John Alroy, entered by Erin Leckey on 18.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

 Ammonitida - Hammatoceratidae