Franz Gröger was an Austrian geologist who visited South Africa about 1872. He travelled from Cape Town to the diamond fields at Kimberley and on to Natal. His observations on the geology of the country were published in a paper, "Skizze über die Gesteinverhältnisse im südlichsten Afrika", in the Verhandlungen der Kaiserlich-Königlichen Geologischen Reichsanstalt (Austria) in 1873 (pp. 129-136). He recognised three groups of rocks: The Karoo strata; the Table Mountain sandstone, with an associated fine-grained limestone; and various gneisses, granites and schists. For the succession of strata in the south-western Cape he followed that proposed by F.C. von Hochstetter*. In the Karoo he mistakenly thought that there was an unconformity between the Beaufort Group and underlying Ecca beds. He also considered that A.G. Bain's* claystone porphyry in the Karoo and the boulder beds of Natal (later both recognised as Dwyka tillite) were entirely different formations. The eruptive rocks of the Vaal River valley he considered to be of post-Karoo date. He discussed the presence of diamonds in South Africa in a separate paper, "Das Vorkommen der Diamanten in S.A.", in the same journal (1873, pp. 310-312).
Between 1876 and 1879 he published nine more papers in Austria, dealing with deposits of mercury ore, antimony in Sarawak and other parts of the island of Borneo, the occurrence of precious metals in western North America, coal deposits, earth tremors and volcanic eruptions.
