he geological focus of this Technical Report is on the aquifer system within the Late Devonian (Frasnian) dolomitized reef structure of the Woodbend Group, Leduc Formation, that conformably overlies the carbonates of the Beaverhill Lake Group. The reef structure is called the Sturgeon Lake Reef Complex, and the LithiumBank Property encompasses most of the complex.
The Leduc Formation is defined by subsurface oil and gas exploration (n=242 wells) that define the true vertical depth of the Leduc Formation at depths of between -2,337.6 m and -3,050.6 m (average -2,619.9 m) below the Earth’s surface. The Leduc reef has a thickness of approximately 230 to 380 m (average and maximum thicknesses of 206 m and 408 m) along a southwest to northeast cross section at the Boardwalk Property (Hydrogeological Consultants Ltd., 2012).
The Beaverhill Lake Group (Swan Hills aquifer) and the Woodbend Group (Leduc aquifer) were thought to be hydraulically connected due to historical government interpretation of Hitchon et al. (1995). A hydrological assessment conducted by HCL has demonstrated the two units – at least in LithiumBank’s Boardwalk Property area – are in fact not connected.
The brine is hypersaline. Reported total dissolved solids (TDS) concentrations of 77 Leduc samples ranged from 113,117 to 265,921 mg/L, with an average of 199,995 mg/L (Hydrogeological Consultants Ltd., 2012).
Mineralization
Lithium mineralization within the Devon ........