Cambrian sediments from the Nigel Pass and Sunset Peak Areas of Jasper Park, Alberta, are the subject of this study. Twenty-six thin sections and three suites of heavy minerals are described.

Cambrian sediments were deposited on a shallow, slowly subsiding shelf area flanking the craton. Lower Cambrian sediments were derived from the craton and Precambrian Beltian sediments.

The presence of glauconite in the Sunset Peak calcareous quartzitic sediments indicates slow deposition in a nearly neutral environment. X-ray and chemical analysis of this glauconite indicate it is ordered and rich in potassium. It has the chemical formula K_1.63 (Na, Rb, Ca) _.06 (Al_2.44 Fe⁺³_.67 Fe⁺²_.22 Mg_.60) (Si_7.00 Al_1.00) O₂₀ (OH)₄. The chemical composition shows this glauconite to be a representative of the aluminum-rich glauconites, which are rare.

Potassium-argon dating of this authigenic glauconite and what appears to be a detrital microcline feldspar from these Lower Cambrian sediments yielded ages of 359, 413 and 344 m.y. respectively. The glauconite age is slightly low because of argon leakage; the feldspar (probably Precambrian) age is close to the 360 million year figure obtained at the University of Alberta for a biotite from the Ice River Complex of the Rocky Mountains and Yukon granites intruded at the time of the Cariboo orogeny. There is a distinct possibility that this feldspar age may reflect in some way the influence of the Cariboo orogeny which White (1959) postulates to have taken place from Late Ordovician through Devonian time.

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