Cross-formational fluid flow in Upper Devonian to Lower Cretaceous strata, west-central Alberta, Canada

Upper Devonian to Lower Cretaceous strata form part of, and are influenced by, two regional-scale hydrogeologic flow-regimes in west-central Alberta. The lower Paleozoic regime comprises the Upper Devonian Hydrogeologic Group and the Mississippian Hydrogeologic Group. The upper Jurassic-Lower Cretaceous regime consists of the Mannville Group Aquifer and the Viking Group Aquifer. Cross-formational flow of formation fluids occurs between and within these flow regimes.;Significant cross-formational flow of water, oil, and gas occurs across the Ireton, Wabamun Group, and Joli Fou aquitards. Saline waters and hydrocarbons cross the Ireton aquitard where it is thin or absent over underlying reef structures. Ascending fluid flow and the thickness of the Ireton aquitard exert a primary control on hydrocarbon trapping in the study area. Upward moving saline water and hydrocarbons cross the Wabamun aquitard where it subcrops the Mannville Group. Cross-formational migration of Paleozoic brines create a saline plume (;Study results demonstrate that regional fluid flow and cross-formational flow play important roles in hydrocarbon migration and entrapment in the subsurface. Hydrogeological and hydrochemical evidence support a hydraulically continuous rock-framework in west-central Alberta. There is no evidence for sealed compartments in the study area. The concept of vertical migration through shales can be used to explore for petroleum reservoirs given the hydraulically continuous rock-framework in the area.