This study has concentrated on the development of the basal part of the Lower Miette Formation in the Tekarra Creek map-area, Jasper. The rocks under investigation, assigned to the Windermere Group, were apparently deposited in a deltaic environment and consist of alternating argillaceous and arenaceous units. In the basal 820 feet the arenaceous units are nearly linear. Two mutually perpendicular trends of sand bodies can be distinguished, striking roughly northwest-southwest in the basal 450 feet, and approximately northeast-southwest in the overlying 370 feet. The basal sands have been interpreted as marginal barrier-island deposits delineating the palaeogeographic shoreline, and represent a destructional deltaic phase. The overlying sands are thought to consist of distributary channel deposits representing a constructional deltaic phase. The sediments appear to have come from an igneous and metamorphic source-area less than 50 miles to the northeast.

At Tekarra Creek the Lower Mietta strata, severely deformed and metamorphosed during the Laramide orogeny, form a series of plunging folds and are cut by a thrust striking subparallel to the fold axes. On the basis of mineral assemblage the rocks have been assigned to the quartz-albite-muscovite-chlorite subfacies of the greenschist metamorphic facies.

Potassium-Argon ages of detrital muscovite from the Old Fort Point, Miette and Jasper Formations range from 1176 ± 9 to 1046 ± 50 m.y. The maximum age, obtained from the coarsest sample, supports the belief that the source area was underlain by rocks of the Churchill Province of the Canadian Shield, which are thought to range from 1600 to 1800 m.y. The degree of up-dating may be a function of grain-size.

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