ABSTRACT: The Upper Devonian Palliser and Wabamun Formations in Alberta, Canada

MEIJER DREES, N. C., Institute of Sedimentary and Petroleum Geology, Calgary, Alberta, Canada, and D. I. JOHNSTON, University of Alberta, Edmonton, Alberta, Canada

The Palliser Formation near Exshaw is about 300 m thick and includes 5 units. It was sampled for conodonts and correlated with sections near Canmore, Banff, and Lake Minnewanka. The basal, dark gray dolostone of unit 1 did not yield conodonts, but the dolomitic limestone of unit 2 includes conodonts of the Famennian, Lower to Upper crepida zones. The peloidal limestones of unit 3 contain conodonts of the Lower rhomboidea to Lower marginifera zones. Unit 4 did not yield diagnostic conodonts. The fossiliferous limestones of unit 5 include conodonts of the expansa to Lower praesulcata zones. Because conodonts of the trachytera and postera zones are missing, it is possible that the sharp contact between units 4 and 5 represents a significant hiatus in deposition.

The carbonates of units 1 and 2 belong to the Morro member and correlate with the three lower members of the Wabamun Formation and the evaporites in the lower part of the Stettler Formation. Unit 2 includes equivalents of the Crossfield member. The interbedded dolostones, carbonate breccia, laminated and silty limestones, and stromatolitic limestones of unit 4 represent the lower part of the Costigan member and correlate with the Cardinal Lake member of the Wabamun Formation and the anhydritic deposits in the upper part of the Stettler Formation.

The fossiliferous beds of unit 5 represent the upper part of the Costigan member and correlate with the Big Valley Formation. Unit 5

and the Big Valley include conodonts of the same zone as found in the overlying dark shales of the subsurface Exshaw Formation. It is thus assumed that unit 5 and the Big Valley Formation are basal transgressive deposits.

AAPG Search and Discovery Article #91012©1992 AAPG Annual Meeting, Calgary, Alberta, Canada, June 22-25, 1992 (2009)