The measured outcrop section T13-R9W4-01 in the Belly River Group, located on the northern side of the South Saskatchewan River valley 32 km west of Medicine Hat, includes the uppermost part of the Foremost Formation and the lower part of the Oldman Formation.
This report includes a graphic log of the measured section with an outcrop gamma curve and a detailed description of the section (avoiding lithofacies interpretation, but detailing stratigraphic context where appropriate) with selected photos.
The exposed Foremost Formation interval appears to lie wholly within the Taber coal zone and consists largely of silty mudstone and siltstone, with subordinate coal, carbonaceous mudstone and very fine-grained sandstone. A 6 to 7 m-thick sandstone interval at the base of the Oldman Formation, immediately above the Taber coal zone, is thought to represent the Herronton sandstone zone. Gamma-ray counts for this interval are markedly lower than those for sandstone of similar grain-size higher in the Oldman Formation, indicating a significant compositional difference.
Hathway, B., Banks, C.J., Hay, D.C. and Mei, S. (2011): Measured outcrop section T13-R9W4-01 of the Foremost and Oldman formations (Belly River Group), Suffield area, South Saskatchewan River valley, southeastern Alberta (NTS 72L/03); Energy Resources Conservation Board, ERCB/AGS