General Geology

Fossil remains were found at numerous localities but those giving best results were along Tahtsa River, near the east end of Nadina Lake and, on Troitsa Peak, and Chikamin Range. Fossils were also found on Tweedsmuir Peak, Mount Sweeney, Nadedikus Mountain, and Holmes Ridge.

H. Frebold and J. A. Jeletzky of the Palzontological section of the Geological Survey of Canada identified the fossil collections and commented on their age and stratigraphic significance.

Collections made in the area are as follows: Northwest ridge of Troitsa Peak

Catalogue No. 13754. H. Frebold Tmetoceras regleyi Dumortier “Polymorphites” cf. senescens Buckman Pleuromya sp. A Arca sp. Indeterminable gastropods Age: Lower Bajocian (early Middle Jurassic)

Catalogue No. 13753. H. Frebold Tmetoceras regleyi Dumortier Pleuromya sp. A Trigonia sp. indet. “Rhynchonella’ sp. indet. Gastropods indet. Age: Lower Bajocian (early Middle Jurassic)

Catalogue No. 13758. H. Frebold Tmetoceras regleyi Dumortier Poorly preserved pelecypods (Pleuwromya?) and gastropods Discinia sp. Age: Lower Bajocian (early Middle Jurassic)

Frebold (1951, p. 20) remarked that Tmetoceras regleyi Dumortier has hitherto been unknown in Canada and that it represents an early Bajocian horizon. Its stratigraphic position is older than that of the widespread Lower Yakoun fauna (Stephanoceras and Chondroceras) of British Columbia and its equivalents in the Fernie group of Alberta, but younger than faunas with Harpoceras, Fanninoceras, and Dactylioceras (found at various places in British Columbia and Alberta) which, as stated by McLearn, belong to the Toarcian. As stated previously, this bed is not the bottom of the Troitsa section but is underlain by volcanic rocks some of which may possibly reach into the Lower Jurassic.

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