Open File Report 2014-10

Open File Report 2014-10

OFR 2014-10

Three-Dimensional Hydrostratigraphic Modelling of the Sylvan Lake Sub-Basin in the Edmonton-Calgary Corridor, Central Alberta

Author(s) Atkinson, L.A. Glombick, P.M. Date 2015-02-03

The Sylvan Lake sub-basin (SLSB) regional scale groundwater study in central Alberta produced a multilayer hydrostratigraphic model representing the vertical and lateral distribution of depositional patterns in the study area. This model provides a geological framework for the mapping and numerical modelling of groundwater flow and chemistry.

The subject of this report is the methodology and results of the modelling of the SLSB, focused on Neogene-Quaternary sediments and Upper Cretaceous-Paleogene bedrock units. The SLSB was selected as a priority sub-basin because of the increasing demands on water resources in the area for unconventional hydrocarbon resource development and the Town of Sylvan Lake municipal water supply.

The hydrostratigraphic model of the SLSB shows the distribution of informal hydrostratigraphic units in the Paskapoo Formation and overlying Neogene-Quaternary succession, and provides formal lithostratigraphic bounding surfaces of the Paskapoo, Scollard, Battle, Wapiti, and Lea Park formations. Structure elevation grids represent the bounding surface of each stratigraphic unit in the modelling domain, interpolated using RockWorks15 and ArcMAP.

Further internal characterization of the highly heterogeneous Paskapoo Formation is provided because it is a regionally significant bedrock aquifer in the study area. Slice mapping analysis was used to divide the formation into zones dominated by potentially permeable sandstone bodies, using net-to-gross sandstone maps. All structure elevation tops and polygons delineating coarse-grained bodies in the Paskapoo Formation have been formatted for input into groundwater flow models.