Illustrations of Canadian fossils, Early Lower Cretaceous, Berriasian and Valanginian, of the Canadian western Cordillera, British Columbia

The Great Tonalite Sill (GTS) of southeastern Alaska and British Columbia (Brew & Ford 1981; Himmelberg et al. 1991) is one of the most remarkable intrusive bodies in the world: it extends for more than 800 km along strike and yet is only some 25 km or less in width. It consists of a belt of broadly tonalitic sheet-like plutons striking NW–SE and dipping steeply NE, and has been dated between 55 Ma and 81 Ma (J. L. Wooden, written communication to D. A. Brew, April 1990) (late Cretaceous to early Tertiary). The sill (it is steeply inclined and rather more like a “dyke”) is emplaced along the extreme western margin of the Coast Plutonic and Metamorphic Complex (CPMC), the high grade core of the Western Cordillera. The CPMC forms the western part of a group of tectonostratigraphic terranes including Stikine and Cache Creek, collectively known as the Intermontane Superterrane (Rubin et al. 1990). To the W of the GTS, rocks of the Insular Superterrane, including the Alexander and Wrangellia terranes and the Gravina belt, form generally lower metamorphic grade assemblages. The boundary between these two superterranes is obscure but it may lie close to, or be coincident with, the trace of the GTS.

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The walking speed of dinosaurs from the Peace River Canyon, British Columbia, Canada

Canadian Journal of Earth Sciences ◽

10.1139/e81-077 ◽

1981 ◽

Vol 18 (4) ◽

pp. 823-825 ◽

Cited By ~ 3

Author(s):

Richard Kool

Keyword(s):

British Columbia ◽

Lower Cretaceous ◽

Walking Speed ◽

Peace River

The walking speed of seven dinosaur ichnospecies from the Lower Cretaceous Peace River Canyon, British Columbia, Canada, have been determined. The speeds range from approximately 1 to 3 m s−1 (4–10 km h−1).

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Foraminiferal inventory and lithologic description of the Lower Cretaceous (Albian) Hulcross Shale, Monkman area, northeastern British Columbia

Canadian Journal of Earth Sciences ◽

10.1139/e88-076 ◽

1988 ◽

Vol 25 (5) ◽

pp. 793-798 ◽

Cited By ~ 8

Author(s):

C. R. Stelck ◽

Dale Leckie

Keyword(s):

British Columbia ◽

Water Column ◽

Lower Cretaceous ◽

Volcanic Ash ◽

Peace River ◽

Low Degree ◽

Bottom Waters

Correlation of an arenaceous microfauna of 41 species (44 subspecies) from the Hulcross Formation of the Monkman Pass area with that found in the Hulcross Shale on the Peace River has a further corroboration in matching spectra of volcanic ash beds at both localities. The Monkman Pass equivalents of both the basalmost portion and the upper part of the Hulcross beds on the Peace River are in sandy to continental facies. Diatoms are plentiful in the Monkman Pass section in the shaly facies.The foraminiferal genera include Bathysiphon, Thuramminoides, Psammosphaera, Hippocrepina, Saccammina, Reophax, Glomospira, Ammodiscus, Psamminopelta, Haplophragmoides, Ammobaculites, Trochammina, Textulariopsis, Pseudobolivina, Verneuilinoides, Uvigerinammina, Gaudryina, Eggerella, and Dorothia. Only Thuramminoides, Haplophragmoides, and Trochammina occur in abundance, indicating water of depth around 100 m at time of deposition and of salinity close to that of normal seawater. The low degree of bioturbation and the presence of Chondrites in the lower Hulcross suggest that poorly oxygenated bottom waters prevailed. Upwards, the diversity and abundance of bioturbation increase, indicating higher oxygenation contents caused by better circulation. As such, the Hulcross basin had a stratified water column.

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