Summary:
All operations under Elk Valley Resources (EVR) (Elkview, Greenhills, Fording River, Line Creek) are situated within the Elk Valley Coalfields and are hosted in the Upper Jurassic to Lower Cretaceous Kootenay Group strata. The principal coal-bearing unit is the Mist Mountain Formation, which is enclosed by the Morrissey Formation below and the Elk Formation above. The coal seams within the Mist Mountain Formation range widely in thickness and rank, producing both hard and semi-hard coking coal, with coal quality influenced by burial depth and structural deformation. Common structural features include complex folding, faulting, synclines, and repeated seam horizons. Most operations contend with structural repetition due to thrust faulting and variable bedding dips, requiring dense drilling in structurally complex zones.
Elkview Operations
Located in the northern part of the Crowsnest Coalfield, Elkview is geologically defined by the Sparwood (Michel) Syncline, a southwest-plunging structure, and intersected by multiple thrust and normal faults. The formation dips westward at about 20°, with a gentle southern plunge. Structural deformation is prevalent, especially along fault boundaries, resulting in repeated seams and localized thickening, such as the basal 10-seam. Coal seams lie within the Mist Mountain Formation and range from low to high volatile bituminous rank. Geologically complex areas, particularly around Baldy, Adit, and Natal Ridges, necessitate increased drilling to manage seam continuity and quality. Approximately half the deposit is categorized as geologically complex.
The major structure in the Project area is a southwest plunging syncline, the Sparwood (Michel) Syncline. Multiple thrust faults and normal faults occur throughout the Project area, mostly striking in a northwest to southeast orientation. The thrust faults generally dip west to southwest at inclinations of 20–50°. This has resulted in coal seam repeats and structural deformation and complexity along the thrust fault boundaries, by overlapping and drag folding.
The tectonic thickening of the basal 10-seam is an important factor in mine planning.
The Mist Mountain Formation depth of burial ranges from surface exposures to >750 m. The coal measures on the EVO contain bituminous grade coal seams with varying volatile matter contents. The coal quality varies with depth of burial and location along the strike of the deposit. Seams may range in thickness from <1 m to >15 m.
Seams range in rank from high to low volatile bituminous and are numbered from 10 at the base, upwards to 1, with additional seams A through D at the top of the 600 m thick stratigraphic column. All mineable coal seams in Baldy, Adit and Natal Ridges are within the Mist Mountain Formation. A portion of the Fernie Formation occurs at the top of Adit Ridge.
These are the areas in which over thrusted repeats of 10-seam may be found due to the thrust fault thickening, and as such, required an increased drilling density to maintain the geological assurance. Zones of complex geology pass through Baldy Ridge, Adit Ridge and Natal Ridge and are adjacent to the fault lines. About half of the deposit at EVO is classified as complex, with the remaining half classified as moderate.
Greenhills Operations
Greenhills lies within the Elk Valley Coalfield, between the Alexander Creek and Greenhills synclines. The distribution of the coal seams is controlled by major structural boundaries, including the Bourgeau Thrust and the Erickson Fault. The synclines host sheared and fragmented seams, particularly thicker seams in lower stratigraphy that have been disrupted by thrust faulting. Structural dips vary considerably, steepening near fault zones, with the Greenhills Syncline plunging gently to the north before thinning out. The Mist Mountain Formation at Greenhills contains bituminous-grade seams, some exceeding 16 meters in thickness, and exhibits burial depths beyond 1,500 meters.
At Greenhills, up to 24 coal seams occur in the Jurassic-Cretaceous Mist Mountain Formation (Kootenay Group) interbedded with sandstone, siltstone and shale. The major seams, which are continuous throughout the area, are named 1, 7, 10, 16 and 20. Seams 1, 7 and 10 (68 per cent of in place geological reserves) are medium volatile bituminous coal, while seam 16 and other stratigraphically higher seams are high volatile A bituminous in rank. Other major seams are lenticular and less extensive (several kilometres extent) and occur generally in the upper half of the Mist Mountain Formation. Thicknesses of the major seams are as follows from oldest to youngest; seam 1 (10 to 16 metres), 7 (7 to 11 metres), 10 and 10L (5 to 11 metres), 16 and 16L (5 to 11 metres, and seam 20 (2 to 7 metres).
Fording River Operations
This operation is also within the Elk Valley Coalfield and shares geological features with Greenhills. The coal seams are mined from Eagle, Castle, and Turnbull mountains, and from pits in the Swift and Lake Mountain areas. Structural control is exerted by the same synclines and bounding faults seen at Greenhills. Seam fragmentation and shearing are widespread, especially where thick seams coincide with thrusting. The coal varies from low to high volatile bituminous, with thicknesses reaching over 70 meters in synclinal and anticlinal noses. Fording River exploits multiple seam sets depending on pit location, each contributing to HCC and SHCC production.
Line Creek Operations
The Line Creek area includes a broader stratigraphic range starting with older units such as the Rundle and Spray River Groups and continuing upward through the Fernie and Kootenay Groups. The Mist Mountain Formation remains the primary coal-bearing unit, flanked by the Moose Mountain Member below and the Elk Formation above. Burnt Ridge North, a key feature, lies on the west limb of the Alexander Creek Syncline. Structural complexity increases along this limb due to secondary folding and faulting, especially near the east side of Burnt Ridge, where drag folds, shearing, and overturned bedding are present. Seven major seams are mined here, with individual thicknesses up to 22 meters and steep dips on both flanks of the ridge.
At the Line Creek operations, sixteen coal zones (E, D, C, B, A, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10B and 10A, from top to bottom) with a net aggregate thickness of 67.4 metres in 91.7 metres of gross aggregate coal section, occur in the Jurassic-Cretaceous Mist Mountain Formation (440 to 500 metres thick) (Kootenay Group) interbedded with sandstone, shale and siltstone.
The main seams are the 10B seam (average thickness 4.5 metres - thins north); 9 seam (two seams, average thickness 5.4 metres in a 6.4 metre zone - thins north and west); 8 seam (thickest seam - averages 11.6 metres in a 12.8 metre thick coal zone); 7 seam (averages 5.2 to 6.3 metres); 6 seam (two seams average 5.0 metres and 12.0 metres respectively - thickens southwest); 4 seam, which in the south is two seams, 5.0 and 12.5 metres respectively, and in the north is a single thick seam but with a shale split in the northeast, 11.6 and 12.0 metres respectively; 3 lower seam (single or multiple thin seams - 3.3 to 3.8 metres, disappears to the northwest); 3-Upper seam (4.0 to 6.0 metres average thickness, lower 50 to 75 per cent is a single coal seam with thin variable shale splits, upper portion consists of multiple thin coal seams with shale partings); and A seam (2 seams in the south, single thick seam in the north, average thickness is 3.0 to 4.0 metres). The remaining seams are commonly multiple, thinner (less than 3.0 metres) and tend to contain shale partings.
Ash contents range from 5 to 16 per cent (generally 7 to 8 per cent), volatile matter from 19.5 to 30.0 per cent and sulphur from 0.3 to 0.9 per cent (air dried basis). The coal is medium volatile bituminous in rank.