...Figure 3. Stratigraphic cross-sections through the Firebag sub-basin with the top of the Wabiskaw Member as the datum. Gamma ray and density porosity logs are shown for all wells, and dipmeter logs where available. A–A′ is an east–west section that demonstrates the truncation of regional PSS...

... and E marker beds exposed along the sub-Cretaceous paleotopography. Firebag Member marker beds ( Figs. 6 and 8A ) can be traced for more than 100 km across the central and northern Athabasca Oil Sands Deposit, from areas with 200–250 m thick undisturbed salt beds to areas with partially...

... represents the last and most extensive transgressive event in the Lower Elk Point Subgroup (e.g. Moore, 1993 ). The previous transgressive-regressive cycles of the Alberta sub-basin are not recorded in the non-marine sediments on the Athabasca Arch of the AOSMR. In gamma-ray logs, the transition from...

...Georgia L. Hoffman The name “Steepbank Formation” is proposed for a paleokarst diamictite deposit that is present along the margins of the Middle Devonian Prairie Evaporite Formation in the Western Canada and Williston sedimentary basins, including the eastern portion of the Athabasca Oil Sands...

...) for geochemical characterization. Results from these natural seepage zones provide previously unavailable context on the setting of groundwater–surface-water interaction along the lower Athabasca River. The Athabasca River sub-basin forms a major headwater tributary of the northward draining Mackenzie...

...]). Generalized cyclicity and stratigraphic units are adapted from Mossop and Shetsen (1994) and others. (B) Mannville clastic wedge in the eastern Western Canadian Sedimentary Basin overlies Paleozoic carbonates at the sub-Cretaceous unconformity and includes the McMurray Formation (characterized by channel...

... shales of the Waterways Firebag Member. (a) 100/13-07-097-07W4M00, (b) 100/07-12-097-08W4M00. Core tubes are 75 cm long. Over two thousand coreholes confirm that the Waterways Formation forms the subcrop beneath the sub-Cretaceous unconformity at Kearl. The majority of these penetrations are less...

... and Cold Lake areas in eastern Alberta and western Saskatchewan, and detrital zircon (DZ) sample locations from the Imperial Oil Ltd. Athabasca Muskeg, Athabasca Firebag, and Cold Lake leases. The Assiniboia paleovalley corresponds to the thicker lower Mannville on the east side of the basin, where Cold...

... of a variety of carbonate depositional systems including the platform deposits of the Cooking Lake and Majeau Lake Formations, the reefal bodies found within the Leduc Formation, the carbonate platform sediments of the Grosmont Formation, and the basinal shales of the Duvernay and Ireton Formations ( Switzer...

... with subordinate anhydrite, dolomite, shale, and limestone that precipitated in a silled, hypersaline basin. Tectonic tilting of Devonian strata in the region brought the Prairie Evaporite Formation to near-surface depths, where the evaporites dissolved. Where dissolution was rapid and intense, overlying strata...

... subgroup are largely controlled by regional-scale topography on the sub-Devonian unconformity surface. This topography includes the central and northern Alberta sub-basins, which were two major depocentres, separated by the Peace River– Athabasca Arch ( Moore, 1993 ) ( Fig. 3A ). The base of the Lower Elk...

... Evaporite (Middle Devonian) buried evaporite basin. Salt dissolution-induced collapse–subsidence of the overlying Upper Devonian strata is widely recognized as being largely responsible for reconfiguration of the sub-Cretaceous structure ( Ranger and Gingras 2001 , 2006 , 2010 ; Ranger 2010 ; Hein et al...

... prior to being covered by Cretaceous sediment, or not at all, preserved an unconformity configuration that was both pre-Cretaceous and sub-Cretaceous. The Western Canadian Sedimentary Basin evolved as a foreland basin by the Middle-Late Jurassic. The Cordilleran fold and thrust fault belt...

.... The lower boundary has to be drawn in context of a transitional and dolomitized unit of about 20 ft (6 m approx.) thickness without diagnostic macrofossils, but with lenses of “lagoonal” ostracodes assigned to the low-diversity Upper DM4 sub-assemblage. In contrast, the upper boundary is sharply expressed...

... only in basinal or near reef settings. A zonation based on ostracodes has been developed in southern District of Mackenzie and northeastern Alberta (Braun, 1968, 1990; Braun and Lethiers, 1982). It includes six zones with associated sub- zones, but distribution of the taxa is controlled by uncertain...

... plus the Firebag and lower part of the Calmut members of the Waterways Formation. It corresponds approximately to the lower Flume Formation and its basinal equivalents in the Jasper basin, as exposed in the northern Rocky Mountains. The base of the sequence is interpreted to occur beneath...

... on the location of the La Crete sub-basin in northern Alberta, and the distribution and nature of Keg River Formation buildups and the overlying evaporite strata within this depositional realm. Net-evaporite mapping gives a robust picture of the distribution of Upper Elk Point subgroup evaporites, and allows...

... of a vertical or sub-vertical extension fracture may imply that horizontal strain could be quite large. Jahr et al. (2008) used the vertical deformation and tilt change to describe the ground deformation. Although horizontal deformation was not their focus, its influence is incorporated into the tilt change...

.... , and MacEachern , J. 2019 . Earliest Cretaceous transgression of North America recorded in thick coals: McMurray Sub-basin, Canada . International Journal of Coal Geology 204 : 18 – 33 . doi: 10.1016/j.coal.2019.01.011 . Schneider , C. , and Grobe , M. 2013 . Regional cross-sections...