GHO is located within the Elk Valley Coalfields. The coal measures are situated within the Upper Jurassic to Lower Cretaceous Kootenay Group sediments.
From earliest to latest, the Kootenay Group includes:
• Morrissey Formation: sandstones; subdivided into the Weary Ridge and Moose Mountain Members; 20–80 m in thickness;
• Mist Mountain Formation: interbedded sandstone, siltstone, mudstone, shale and thin to thick seams of bituminous to semi-anthracite coal; 450–550 m in thickness;
• Elk Formation: interbedded sandstone, siltstone, mudstone, shale and locally thick beds of chert-pebble conglomerate and thin seams of high volatile bituminous coal; 350–450 m in thickness.
The Mist Mountain Formation contains approximately 25 coal seams of potential economic interest, consisting of medium to high volatile bituminous coal.
Within the coal measures, there are three structurally-separated coalfields, the Elk Valley, Crowsnest, and Flathead coalfields. The Elk Valley coalfield is located within the Alexander Creek and Greenhills synclines, which are separated by a normal fault. The western edge of the Mist Mountain Formation, and therefore the distribution of the Elk Valley coalfield, is controlled by the Bourgeau Fault. To the east of this fault, the Greenhills syncline plunges to the north, and its eastern limb is truncated by the north-trending normal Erickson fault. East of the Erickson fault is the Alexander Creek syncline, which ........