Sequence stratigraphy and facies analysis of the viking formation in crossfield and adjacent areas, Alberta, Canada

The Lower Cretaceous Viking Formation is a siliciclastic unit that accumulated in the Western Interior Seaway and produces hydrocarbons in the Crossfield and surrounding area. The study area encompasses Townships 24–31, Ranges 28W4 to 4W5 in Alberta, Canada. Sedimentological and ichnological observations of 54 cored wells, coupled with the analysis of 1415 geophysical well logs allowed the generation of a high-resolution sequence stratigraphic framework. The Viking Formation is subdivided into four discrete depositional sequences (Sequences 1-4), but this study focuses on Sequence 3, as it constitutes the main cored interval in the Crossfield area. Sequence 3 includes eleven sedimentary facies that are grouped into three facies associations (FA1-3). Deposits of FA1 correspond to the transgressive system tract. The overlying highstand system tract encompasses FA2 and FA3. FA3 contains the reservoir sandstone interval, and comprises sanding-upward successions interpreted to represent deposition in a mixed-process wave-dominated, fluvial-influenced symmetric delta.