GSC C-118573, Twenty Mile Creek (Cretaceous of Canada)

Also known as MVA(F)85-170

Where: British Columbia, Canada (49.5° N, 122.0° W)

• Paleocoordinates: 51.6° N, 52.9° W (Wright 2013)

• coordinate stated in text

• outcrop-level geographic resolution

When: Brokenback Hill Formation, Hauterivian (132.6 - 125.8 Ma)

• Grey tuffaceous sandstone of Brokenback Hill Formation. The Brokenback Hill Fm ranges from upper Valanginian to middle Albian in age. All colllections have relatively fine temporal resolution however due to ammonite biostratigraphy. SPECIFIC AGE DATA: Contains Inoceramus paraketzovi, which indicates a late Hauterivian age, although Arthur et al. suggest a possible Barremian-late Hauterivian age. Entered as Hauterivian following interpretation of Arthur et al.'s discussion.

• bed-level stratigraphic resolution

Environment/lithology: offshore; tuffaceous, gray sandstone

• Relatively deep water conditions, quiet water, soft substrate, some wave action, occasional ripple marks, fairly proximal volcanic source.
• SPECIFIC DATA: Grey tuffaceous sandstone; GENERAL INFORMATION: The Brokenback Fm is mainly green crystal tuff, volcanic conglomerate, and tuffaceous sandstone.

Size class: macrofossils

Reposited in the GSC

Collection methods: quarrying,

• Collections made in 1985by A.J. Arthur and P.L. Smith; collections reposited in the GSC.

Primary reference: A. J. Arthur, P. L. Smith, J. W. H. Monger and H. W. Tipper. 1993. Mesozoic stratigraphy and Jurassic paleontology west of Harrison Lake, southwestern British Columbia. Geological Survey of Canada Bulletin 441:1-62 [A. Miller/A. Hendy/M. Clapham]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 57078: authorized by Austin Hendy, entered by Austin Hendy on 01.12.2005

Creative Commons license: CC0 (CC0)

Taxonomic list

• Authoritative nomeclature.
Bivalvia
 Myalinida - Inoceramidae
Inoceramus paraketzovi clam
Inoceramus paraketzovi acutus
Cephalopoda
 Belemnitida - Belemnitidae
Acroteuthis (? Acroteuthis) sp. Stolley 1911 belemnite