The stratigraphy of the Witbank Coalfield consists of five seams numbered from oldest to youngest: No 1 to No 5 Seam. The seams vary in thickness from less than 0.5 metres to over 6 metres and do not exceed 300 metres in depth from surface. The coal seams dip at less than 5°. However, coal seam morphology and qualities may be locally influenced by basement topography, surface weathering and intrusion of dolerite dykes and sills. The coal qualities vary both within and between individual coal seams.

Low-quality coals, suitable for the local steam coal market, have a calorific value of between 18 to 22 MJ/kg, whereas the high-quality export steam coal has a calorific value of greater than 27 MJ/kg. All five coal seams are developed on Goedgevonden. The No. 1 Seam is of low quality, thin and only developed in paleo-low areas. The No. 2 Seam is extensively developed and is of good quality and is, on average, 6 metres thick. The No. 3 Seam is of good quality but, with an average thickness of only 0.3 metres, is uneconomic. The No. 4 Seam, being closer to surface and although of the same thickness as the No.2 Seam, is influenced by weathering and is not as extensively developed. The No. 5 Seam is of good quality, but is preserved as erosional remnants on the high ground only and thus not extensively developed over the area. No major faults, structural disturbances or intrusives were observed in the boreholes drilled to date.

Open-cut mining methods are utilised at Goedgevonden Coal Mine. Opencast dragline mining operations in the area are extracting the No. 2, No. 4 and No. 5 Seams. The open-cut mine produces both export and domestic thermal coal.

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