F.A. Stoakes, 1992. "Early Mississippian Megasequences", Devonian-Early Mississippian Carbonates of the Western Canada Sedimentary Basin: A Sequence Stratigraphic Framework, Jack Wendte, Frank A. Stoakes, Clarence V. Campbell
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Early Mississippian sediments of the Western Canada Sedimentary Basin comprise a thick sequence of basinal shales, shallow-water carbonates and isolate Waulsortian reefs. The sediments described in this section are assigned to the uppermost Wabamun Group and the Exshaw Formation of largely Famennian age and the Banff, Pekisko and Shunda formations of Tournaisian age (Figure 1). This section comprises at least two transgressive-regressive cycles of sedimentation. The lowermost cycle, termed the Banff cycle by Stoakes, (1987a), actually commences in the uppermost Wabamun (Figure 2). It terminates with progradation of ramp deposits of the lower part of the Pekisko Formation. The second cycle commences with backstepping of the Pekisko ramps and initiation, in downslope positions, of isolate Waulsortian reefs. The cycle terminates with progradation and basin-filling of the Shunda Formation. Although the overall picture is still not that clear it would appear that each Mississippian cycle represents increased reflooding of the WCSB and as such is part of a much large depositional phase. The area where these patterns are perhaps best known is in the area of the Peace River Arch where an anomalously thick sedimentary succession of Carboniferous age is preserved (O'Connell, 1990).