After the announcement of major shale gas discoveries in the Liard Basin in 2012, Petrel Robertson Consulting Ltd. (PRCL) commenced a six-month study on behalf of Geoscience BC to study deep subsurface aquifers in support of systematic sourcing and disposal of waters used for unconventional hydrocarbon development.
Relevant well data were collected across aquifer intervals from public and proprietary sources and supplemented with regional geological mapping and information from outcrop. Regional correlations were created by building a grid of regional stratigraphic cross-sections tied to core and sample cuttings data; these formed the basis for picking a stratigraphic database focused on potential aquifer intervals. Hydrogeological characterization was undertaken drawing on a well test database consisting of 256 tests from 157 well entities. Drillstem tests were used to interpret formation permeabilities and reservoir pressures.
Four aquifer intervals were investigated in detail:
- Mississippian platform carbonate rocks comprising the Rundle Group, including the Debolt Formation and the younger Fantasque Formation;
- Mattson Formation sandstone;
- Lower Cretaceous sandstone including chinkeh and Scatter Formations; and,
- Upper Cretaceous Dunvegan Formation sandstone and conglomerage.