Investigation of Late Cretaceous and Tertiary non-marine strata of west-central Alberta has been undertaken for the Research Council of Alberta to solve problems of origin, correlation and age, structure, and nomenclature. Sediments are exposed in or underlie a belt extending from the Foothills northeast to the line Drumheller-Edmonton-Whitecourt and from Calgary-Drumheller northwest to the Athabasca River. Units of immediate concern include Edmonton, Brazeau, Paskapoo, and Saunders. Abundant well records afford an opportunity for correlation between northeastern and southwestern outcrop belts, as well as to study regional and local sedimentary patterns.

Purpose of this paper is to present the results of preliminary subsurface studies of regional relationships among the non-marine strata that are exposed in various areas. On the northeast, formations include the Belly River, Bearpaw (marine), Edmonton (all Cretaceous) and lower Paskapoo (Tertiary). The part of the section commonly recognized as Cretaceous is approximately 2,600 feet thick. Except for the marine Bearpaw, the units are almost entirely non-marine, composed of lenticular shales, siltstones, sandstones, and coal beds. Similar rocks, assigned to the Paskapoo, overlie the Edmonton.

In the subsurface, near Lacombe and not far west of Edmonton, the Bearpaw passes into terrestrial beds, so that non-marine units are not so easily separated. Southwestward, the entire sequence becomes coarser (sandstones more abundant, and coarser-grained), and thickens markedly on the order of 20 feet per mile, across the strike and toward the Foothills. Equivalent units in and near the Foothills include those called the Brazeau, Saunders, and Paskapoo, but published correlations are open to question.

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