The Lower Cretaceous Basal Quartz (BQ) of the Western Canadian Sedimentary Basin (WCSB) is the basal part of the Lower Mannville Formation, which, together with the overlying Upper Mannville, is considered one of the most prolific hydrocarbon-bearing succession sin the WCSB. However, due to the reservoir complexity often associated with low accommodation fluvial settings, detailed stratigraphic studies are required to fully exploit the potential. Preliminary findings of this chemostratigraphic study on the Horsefly, BAT, and Ellerslie units show that considerable and systematic elemental variation exists between the claystones of the three units. These variations allow the stratigraphic affinity of a claystone core sample to be determined using chemostratigraphy, thereby demonstrating that the technique is a viable additional stratigraphic tool in the WCSB, and more generally, in low accommodation fluvial settings.