Abstract

The Zululand Cretaceous succession has long been a subject of contention. Some authors (Van Hoepen 1926,, 1929,, 1957; Heinz 1930; Venzo 1936) have regarded it as a continuous sequence from Aptian to either Gampanian or Maastrichtian; others have followed Du Toit (1954) in questioning the presence of Turonian rocks, on regional and tectonic grounds.

We have recently examined critical exposures from the Mozambique border south to the northern Transkei (Fig. 1), as a result of which it is clear that a major unconformity exists within the Upper Cretaceous. Uppermost Cenomanian and Turonian rocks are missing, and the Coniacian progressively oversteps Middle Cenomanian to Aptian, and eventually rests on various horizons down to the Ordovician Table Mountain Sandstone.

The most important localities lie along the Umsinene River, Zululand (Fig. 2). Here, coarse clastic pre-Upper Aptian Cretaceous sediments rest on Jurassic Lembombo rhyolites and are locally overlain by Upper Aptian marine sediments. The Albian/Aptian boundary is a non-sequence, followed by an expanded succession up to the Upper Albian Stoliczkaia dispar Zone. The succeeding Genomanian is well-represented at Skoenberg Hill (Fig. 2), where there is a complete transition up from the Albian. The Lower Cenomanian is relatively thin, and is followed by the Middle Cenomanian fauna described by Crick (1907).

The Cenomanian sediments are rather poor in fossils in the upper part and can be traced over the northern and southern flanks of Skoenberg. They are terminated sharply by an erosion surface, overlain by a thin Trigonia conglomerate. Below this conglomerate, silts and

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