In the main coal-bearing section of the Jurassic-Cretaceous Kootenay Group (Mist Mountain Formation), one or two seams 4.6 to 6.1 metres thick occur in addition to up to three seams 1.8 to 3.05 metres thick. The total thickness of coal varies from 9.1 to 15.2 metres. The coal is low volatile bituminous in rank and is interbedded with siltstone, shale and sandstone. Coal seams may change thickness quite rapidly along strike. Samples taken from three seams show volatile matter contents ranging from 20.5 to 28 per cent, ash from 6.8 to 22.6 per cent, fixed carbon from 56.2 to 67.4 per cent, sulphur from 0.42 to 0.60 per cent and phosphorous from 0.033 to 0.038 per cent. Tonnage calculations at the Greenhills Block have yielded estimates of 108 million tonnes and 54 million tonnes, above and 183 metres below an adit (at 1402 metres elevation) respectively. Total indicated reserves are 108 million tonnes (Coal Assessment Report 261).

The structure in the area is dominated by the Alexander Creek syncline, a major, broad, northwesterly trending, north plunging (5 to 10 degrees) syncline. The Aldridge Block lies on the east limb and dips vary from 30 to 60 degrees west. The Greenhills Block lies on the west limb of the syncline which at this latitude plunges approximately 10 degrees northwest. Two subsidiary folds, an anticline in the west and a syncline in the southeast, occur associated with the main fold. They both trend northwest. Dips on the east limb of the minor syncline are approximately 20 degrees, while in the remainder of the block, dips are less than 15 degrees in the north and greater than 15 degrees in the south.

A major north-northwest trending fault, the Erickson normal fault (downthrown towards the west), occurs towards the east of the area. At least one northwest trending, west dipping thrust fault is also present, such as the fault south of Britt Creek.

Fording River Coal began operations at Greenhills (082JSE007) in March 1993.