According to the geology excerpt from the Eloff MWP (Exxaro Coal Central, 2016), the region consists of the following pre-Karoo lithologies, i.e. granite basement rocks of Archean age, quartzite of the Witwatersrand Supergroup, lava of the Ventersdorp Supergroup, dolomite (Malmani Subgroup), chert, quartzite and shale from the Pretoria Group (Transvaal Supergroup). These are overlain in places by the Karoo Supergroup which consists of diamictite (tillite) of the Dwyka Group followed by sandstone, shale, mudstone and coal of the Vryheid Formation.

Local geology of the project area, indicating that the site is underlain by lithologies of the Vryheid Formation (Ecca Group), localized dolerite intrusions and younger alluvium. The Vryheid Formation consists of beds of soft, dark grey sandy shale, which alternates with thick beds of yellow to white cross-bedded sandstone and grit with a few coal seams.