The stratigraphy of the Lower Beaufort Group in an area north of Laingsburg, South Africa

Abstract A detailed section measured across the lowermost Beaufort Group (Late Permian-Early Triassic) in the south-western part of the main Karoo basin confirmed that the DR-3 uranium deposit is situated in the Leeuvlei Member, nearly 1000 m below the top of the Abrahamskraal Formation, and biostratigraphically near the middle of the Tapinocephalus Assemblage Biozone. This is an example of how an integrated application of lithostratigraphic and biostratigraphic methods was used to determine the stratigraphic position of an ore deposit. A detailed paleontological investigation has led to further subdivision of the Tapinocephalus Assemblage Biozone on fossil data. A faunal reversal where dinocephalian fossils are replaced stratigraphically by those of dicynodonts, was found to coincide with the Koornplaats Member-Wilgerbos Member contact, an easily recognisable lithological boundary. The lithostratigraphic and biostratigraphic columns presented for the Abrahamskraal Formation should aid future regional mapping and exploration for uranium.