Type Locality:

Blairmore area, southwestern Alberta; no specific locality designated. More completed and undisturbed exposures can be seen above Burns' Mine on Sheep River (grid reference 516065, NTS 82 J/10W Mount Rae), just east of the Banff exit on the TransCanada Highway (overturned section; grid reference 027740, NTS 82 O/4E Banff); and in a tributary of Pigeon Creek on the east face of Mount Allan (grid reference 271498, NTS 82 O/3E Canmore).

Distribution:

The Passage Beds crop out in most sections throughout the foothills of Alberta and adjacent parts of British Columbia and form the uppermost unit of the Fernie Formation. Apparently undisturbed sections at Burns' Mine (120 m, 394 ft), and or Mount Allan (185 m, 607 ft) are much thicker than the exposures on Grassy Mountain (80 m, 262 ft), which have previously been suggested as a typical section (Frebold, 1957, p. 32). Similar maximum thicknesses are developed in the northern foothills of the Peace River area. Much thinner developments occur in other sections, e.g., 32.8 m (106 ft) in Canyon Creek, Moose Mountain area.

Lithology:

Lower parts consist of dark grey shales fracturing into small blocky and splintery fragments, elongated, yellow-brown weathering concretions often present. Thin (60 cm, 24 in) silty bands, weathering brown appear higher in the section, imparting a ribboned or banded appearance to outcrops. The abundance and thickness of these siltstones increase upwards through the section and they contain coarser, sandy sediment. They exhibit parallel lamination, hummocky and ripple cross-laminations, bioturbation, sole marks and plant fragments, and some have been interpreted as turbidites (Hamblin and Walker, 1979).

Relationship:

The Passage Beds conformably overlie the Green Beds where these are present, with abrupt changes in color and rock type; elsewhere they lie on the Grey Beds with apparent local conformity, except in Fiddle River northeast of Jasper, where both the Grey Beds and Green Beds are absent and there they overlie the Highwood Member. Overlain conformably by the Weary Ridge Member of the Morrissey Formation (Kootenay Group) in southern areas; Gibson (1979) placed this contact at the base of the first continuous sandstone devoid of the interbedded siltstones and shales typical of the Passage Beds. A similar relationship exists between the Passage Beds and overlying Nikanassin Formation in central-northern Alberta, and the Monteith Formation (Minnes Group) in northeastern British Columbia. Laterally equivalent to the Swift Formation of the Sweetgrass Arch and the upper parts of the Vanguard Formation in the subsurface plains region.

Other Citations:

Frebold, 1957; Frebold et al., 1959; Gibson, 1979; Hamblin and Walker, 1979; McLearn, 1927; Stott, 1967.