An abandoned coal mine is situated in Middle Eocene Coldwater Formation beds (Princeton Group) which are in fault contact with Upper Triassic Nicola Group volcanic flow rocks to the east. Coldwater Formation lithologies consist mainly of locally crossbedded, poorly indurated limonite-cemented sandstone, grey shale and coal- bearing beds. Bedding strikes north and dips 20 degrees to the west. The coal seam is approximately one metre thick.