Abstracts Earth and Environmental Sciences

Sedimentology, diagenesis and reservoir characteristics of the Devonian Simonette (Leduc Formation) and Ante Creek (Swan Hills Formation) fields : a comparison between a limestone and dolomite field, west-central Alberta basin

by Luc. Rock

The Simonette and Ante Creek reservoirs are part of a series of extensive Upper Devonian reef complexes or buildups in the West-central Alberta Basin. Buried at depths of about 3510 and 3380m, they are one of the few places in the Alberta basin where dolostone and limestone reef reservoirs can be compared, especially their similarities and differences in reservoir characteristics. Ante Creek's lithofacies are similar to other Swan Hills buildups, and can be subdivided into 7 buildup stages. The Leduc Formation in Simonette can be subdivided into 6 buildup stages, however, facies recognition is difficult as primary textures are obliterated by pervasive replacement dolomitization. Ante Creek and Simonette had a similar diagenetic sequence, except that the relative amounts of the different diagenetic products change between both fields. Vuggy, moldic, intercrystalline, and fracture porosity types predominate in the dolomite Simonette reservoir. Interparticle and intrafossil pore types were mainly observed in the limestones of Ante Creek. (Abstract shortened by UMI.)