Lithology
The formation is composed of siltstone and dark grey shale, with dolomitic siltstone in the base and fine grained sandstone towards the top. The facies is shaley in the north and west of the extent (Fort St. John), silty in the center (Dawson Creek and Pouce Coupe areas) and becomes coarser (sandy) in western Alberta (Valleyview area).
Read more about this topic: Montney Formation