A late Dwyka (early Permian) varvite sequence near Isandlwana, Zululand, South Africa
Abstract A 7.5 m thick varvite association is exposed in a shallow, roadside pit near Isandlwana. The beds lie close to the top of the Dwyka Formation, an important glacial and fluvioglacial association of late Carboniferous to early Permian age. They have been bleached and indurated by igneous intrusion so that even fine sedimentary structures are well preserved and the strata rendered particularly suitable for detailed study. A total of 624 varves and associated beds fall into three stratigraphic divisions, each showing fining upward tendencies in respect of grain size and varve thickness. Remarkable similarities with Pleistocene-Recent lacustrine varves permit reasoned deductions concerning the depositional environment. Recurrent, thin, low-density turbidity currents actively supplemented suspension fall-out as an agent of sedimentation.