“…This group is non¬ marine and was formed by deposition of sediments in deltaic, estuarine and flood plain environments. Fine-grain¬ ed argillaceous sandstones, siltstones, sandy shales, shales with intermixed ironstone layers, calcareous sand¬ stones, carbonaceous shales and coal are typical of the Edmonton Group (Irish 1967(Irish , 1970. Bentonite is an important component of the sediments and forms bentonitic clays, shales and sandstones.…”