Depositional Environment, Petrology, Diagenesis and Reservoir Aspects of the Notikewin Member, Fort St. John Group, West-Central Alberta

Abstract

<p>Thirty-three cores of the Notikewin Member of the Lower Cretaceous Fort St. John Group in the area of the Kaybob Field were examined and sampled.</p> <p>The gas-bearing sandstones and conglomerates were deposited in distributary mouth bars in a wave-dominated deltaic environment. Subsequently, these sediment depocentres are modified by wave energy and littoral currents to form beaches within or adjacent to the delta.</p> <p>Petrographic studies of the chert litharenites to sublitharenites indicate two provenances; medium to high grade metamorphic terrain and a sedimentary source; both of which are in the Cordilleran highlands.</p> <p>The potential of the Notikewin Member as a reservoir is controlled primarily by the presence of sand matrix in conglomerates. In sandstones, scanning electron microscopy indicates that the progressive assemblage of carbonate cement, quartz overgrowths, kaolinite and chlorite partially occlude porosity. The transformation of allogenic illite has no effect on reservoir potential.</p>