Tectonically induced fluid flow in Devonian carbonate aquifers of the Western Canada Sedimentary Basin
Abstract This study investigates paleofluid flow through the Devonian carbonate aquifers in the deep part of the Alberta Basin, Canada, using the distribution and geochemical composition of deep burial, late diagenetic, sparry calcite and dolomite cements, as well as that of the Precambrian metasediments that make up the underlying basement and much of the adjacent Rocky Mountain Main Ranges. The objective of this study is to characterize regional, tectonically induced (squeegee-type) fluid flow in these Devonian aquifers. The data indicate sublateral injection of fluids from a basin-external, probably metamorphic source during deep burial diagenesis in some gas pools close to the deformed belt and/or injection of such fluids via subvertical faults from the metasedimentary basement, or sublaterally via the intervening Cambrian clastics. The fluxes and possible geothermal anomalies during injection of basin-external fluids appear to have been low. Also, tectonically induced fluid flow appears to have been rather limited laterally, extending perhaps only 100–200 km into the foreland basins.