Investigations of the chemical composition, diagenetic changes and fossil remains have been conducted on cores and cuttings samples from Sturgeon Lake, Normandville and Clairmont Upper Devonian reef complexes. By integrating the results obtained with regional stratigraphic features, suggestions are postulated as to the basinal orientation of the reefs and their tectonic history.

It is apparent that reefs developed at Sturgeon Lake and Normandville on gently subsiding platforms in clear, shallow basinal environments. The Sturgeon Lake reef complex, which is remarkably thick, massive and homogeneous lithologically, is indicative of stable conditions during deposition; in contrast to the less stable conditions indicated by cyclic phases of deposition in the Normandville complex. The diagenetic features of the Clairmont and western off-reef Sturgeon Lake sediments suggest a stable shelf or a restricted back reef depositional environment.

Reef development appears to have been abruptly terminated by a major diastrophic event, followed by undulating platform conditions. A slight pivoting about the Peace River high and moderate tilting into the Cordilleran geosyncline was the final tectonic stage in the orientation of the reefs.

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