Approximately 52 metres of coal contained in 12 seams (from stratigraphically oldest to youngest 10, 9, 8, 7, 6, 5, 1, A, B, C Lower, C Upper and D) occur in the Jurassic-Cretaceous Mist Mountain Formation (Kootenay Group), which is approximately 610 metres thick in the area. Only nine seams (aggregate thickness 45-61 metres) are present in Sparwood Ridge South. The seams which are missing in this area are 5, C Lower, C Upper and D. The coal occurs in strata consisting of sandstone, siltstone and shale.

The proven coal reserves in the Sparwood Ridge area are 29,400,000 tonnes in place (1978 Kaiser Resources Ltd., Coal Reserves and Mining Outlook). Ash contents in the raw coal are 15-22 per cent and in coal cleaned at 1.50 specific gravity ash contents are 9.5-10 per cent, volatile matter is 19-26 per cent, sulphur is less than 0.5 per cent, and kilojoules/kilograms values are 32,560.

The structure consists of the roughly north trending, south plunging Sparwood syncline. The ridge forms the west limb of the syncline, on which strata dip approximately 30 degrees east. The sequence is cut by several approximately north-northwest trending, east dipping thrust faults. The faults dip steeper than the strata on the limbs.

The Balmer South mine is located on Sparwood Ridge. The No. 10 seam, which is 12.2-15.2 metres thick and dips approximately 30 degrees east, is mined hydraulically in this area.