. Bulletins of American paleontology. Thornton Creek Member: Day and Whalen 125 118° 114° 110°. ^ Stratigraphic Cross- Section Transect Text-figure 1.—Location maps. A. Detailed location map of the overthrust belt in western Alberta illustrating the locations of the Miette and Ancient Wall platforms (after Mountjoy, 1965). The thick black line indicates the location of the stratigraphic cross section along the southeast margin of the Ancient Wall platform (Text-fig. 3). B. Map illustrating the location of Upper Devonian isolated and attached carbonate platforms in the Alberta basin. Buildups l
. Bulletins of American paleontology. Thornton Creek Member: Day and Whalen 125 118° 114° 110°. ^ Stratigraphic Cross- Section Transect Text-figure 1.—Location maps. A. Detailed location map of the overthrust belt in western Alberta illustrating the locations of the Miette and Ancient Wall platforms (after Mountjoy, 1965). The thick black line indicates the location of the stratigraphic cross section along the southeast margin of the Ancient Wall platform (Text-fig. 3). B. Map illustrating the location of Upper Devonian isolated and attached carbonate platforms in the Alberta basin. Buildups located west of the barbed line (=eastern limit of Laramide thrusting) are exposed in the Canadian Rocky Mountains. The type section of the Thornton Creek Member of the Flume Formation is located along the southeastern margin of the Ancient Wall platform (after Mountjoy. 198(J; Geldsetzer, 1989; Switzer et 1994). Miette and Ancient Wall platforms documented six Frasnian depositional sequences that were interpreted as 3rd order cycles (Text-fig. 3; van Buchem ef 1996; Whalen et al., 2000a,b). These sequences record different styles of platform development, from aggrad- ing ramp to prograding. backstepping and aggrading isolated platforms, to a prograding ramp phase, that were controlled by episodic continental margin subsi- dence and the 2nd order eustatic sea-level trend (van Buchem er 1996: Whalen et 2000b). Major sea level rises that initiated deposition of these six se- quences coincide with Devonian T-R cycle lib, lie and lid sea-level events of the Johnson curve (Johnson et 1985, 1991; McLean and Mountjoy, 1993; Whalen et 2()). Faunal evidence suggests that depo- sition of the Thornton Creek Member appears to cor- relate with the upper subcycle of Johnson et al.'a (1985, 1991) T-R cycle lla, designated as T-R cycle lla-2 by Day et al. (1996). STRATIGRAPHY OF THE THORNTON CREEK MEMBER AT ANCIENT WALL The type section of the Thornton Cr
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