Carboniferous biostratigraphy and correlation, northeastern British Columbia and southwestern District of Mackenzie

Abstract

Regional stratigraphic and fauna distribution data from 5 surface stratigraphic sections and 37 subsurface sections indicate the following ages and stratigraphic relationships within the Lower Carboniferous succession of the area. The Banff Formation (Early? and Middle Tournaisian, Plains), which consists of shale with minor amounts of siltstone and limestone, passes westward into equivalent shale and chert of the Besa River Formation. The Pekisko Formation (Middle Tournaisian, Plains), composed of skeletal limestone and wackestone, and the "Shunda'' Formation (Late Tournaisian, Plains), comprising argillaceous limestone, calcareous shale and minor amounts of skeletal and pelletoid limestone, change facies westward, near the eastern edge of the disturbed belt, into the upper Besa River Formation and Member A of the Prophet Formation, and are equivalent to the upper Clausen and lower Flett formations to the north (southern Mackenzie Mountains). The lower member of the Debolt Formation (Early and Early Middle Visean, Plains), composed of micritic and skeletal limestone, wackestone and calcareous shale, grades westward into the cherty dolomite and limestone of Member B of the Prophet Formation and is correlated with the limestone and calcareous shale of the middle Flett Formation. The upper member of the Debolt Formation (Late Middle and Early Late Yisean, Plains) consists of pelletoid, micritic, argillaceous and skeletal limestone with minor amounts of calcareous shale and dolomite, and is correlative with the cherty, skeletal limestone of Member C and the upper part of Member B of the Prophet Formation, and with the skeletal limestone and calcareous shale of the upper Flett Formation. The cherty carbonates of the Prophet Formation(Late? Tournaisian to Early Late Yisean) occur in the outcrop belt and westernmost plains of northeastern British Columbia and change facies into the Besa River Formation by a progressive increase in shale and chert from base to top toward the west. The Stoddart Group (Early Late Vi sean to Pennsylvanian), which consists of terrigenous elastics and carbonates, occurs in the plains and outcrop belt of northeastern British Columbia, and grades northward into the coarse-grained, partly continental elastics of the Mattson Formation, and westward into the shale of the Besa River Formation. Eleven Middle Tournaisian to Late Yisean foraminiferal zones within the area correspond to zones previously established for the North American Cordillera, and correlate with the original Lower Carboniferous stratigraphic sequence of Eurasia. There is a consistent relationship between the vertical and lateral distribution of foraminiferal zones and associated macro faunal assemblages. With minor exceptions, the combined fauna succession of this area matches that in southwestern Alberta and western United States and forms part of a consistent biostratigraphic scheme applicable to Lower Carboniferous rocks throughout western North America.

Waulsortian-like mounds of the Mississippian Pekisko Formation, Northwestern Alberta: Petrographic and chemical attributes

“…The Pekisko Formation, which is part of the Rundle Group, consists of a progradational shallowing upward sequence (Bamber and Mamet, 1978;Richards, 1989;Richards et al, 1993). In west-central Alberta, the Pekisko Formation forms a broad ramp which thins toward the Peace River Embayment.…”

“…The division of the Debolt Formation into an Upper and a Lower member was made by Macauley (1958). The Upper Member is composed of dolomite, grainstone and micritic limestone, whereas the Lower Member consists of skeletal limestone (Bamber and Mamet, 1978). The Shunda Formation consists of several lithofacies these include: a mixedskeletal facies; algal wackestone facies; and, a fenestralcarbonate facies (Richards et al, 1993).…”

The Organic Petrology and Thermal Maturity of Lower Carboniferous and Upper Devonian Source Rocks in the Liard Basin, at Jackfish Gap-Yohin Ridge and North Beaver River, Northern Canada: Implications for Hydrocarbon Exploration

“…Upper Visdan (V3) to Early Serpukovian age (Patton 1958;Bamber and Mamet 1978;Braman and Hills 1977;Utting 1981) and is thickest (1020 m) at the type section at Jackfish Gap. It is a sandstone-dominated sequence including siltstones, subordinate shales, coals, and carbonates, deposited in deltaic and related environments during several delta cycles (Richards 1989).…”

Stratigraphy, structure and tectonic history of the Pink Mountain Anticline, Trutch (94G) and Halfway River (94B) map areas, northeastern British Columbia

“…The type section of the Prophet Formation is along Bat Creek (80 km northwest of Pink Mountain) within the Trutch map area (Bamber and Mamet, 1978). The Prophet Formation was mapped at the surface along the western halves of the 1:250,000 scale Trutch and Halfway River map sheets (Irish 1970, Taylor et al 1999, Taylor 1979).…”