The presence of Cainozoic marine sediments in the Sperrgebiet, Namibia, was noted as early as 1908 when diamonds were found at Kolmanskop. Because of the economic interest of these deposits, geological investigations were undertaken, which led to detailed mapping of their distribution, initially by Beetz (1926). In the Central Sperrgebiet early investigators correlated the 'highest' beach deposits (ca 160 metres above present-day mean sea-level) to the Eocene, referred to in the old literature as 'Höchster Stand der Eocänsee' or the 'Eocäne Marine Inundation' (Kaiser, 1926). Liddle (1971) extended this " ancient" strandline a few kilometres northwards to Elfert's Tafelberg. Dingle et al. (1983) dated it to the late Palaeocene – early Eocene. In contrast, along the Namaqualand coastal plain in South Africa, marine deposits attributed by Pether (1986, 1994) to the 90 metre package, the 50 metre package, and the 30 metre package were correlated to the Miocene. Keywords: raised beach, miocene, oligocene, eocene, ferruginisation.