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The existence of lignitic deposits (Knysna Formation) on the South African south coast, near to the town of Knysna has been recognised for more than a century. However, a combination of limited study and few natural exposures has meant that the age and stratigraphic position of the Knysna Formation are unclear, despite its potential as a palaeoenvironmental archive. We present a new suite of chronological, geochemical and palynological data obtained from a recently identified lignite exposure in this area. The lignite pollen assemblage is dominated by palms (Arecaceae), which are now locally extinct, and contains additional palynomorphs of tropical affinity, along with (moist-temperate) Podocarpus- type pollen, grasses, and herbaceous pollen types (e.g. Cliffortia -type, Asteraceae). Overall, the assemblage shows some commonalities with the Miocene Elandsfontein Formation in the Western Cape. The lignites are dominated by a diverse range of higher plant biomarkers, including abundant leaf wax lipids, as well as lignin monomers and leaf cuticle-derived macromolecular organic matter. All strongly indicate a terrestrial depositional setting, perhaps akin to contemporary palm swamps. A number of sesquiterpenoids imply the presence of gymnosperms, supporting observations from the pollen data and previously reported macro-fossil finds. The application of isothermal thermoluminescence techniques to coversands overlying the lignite produced a minimum age of ~1.7 Ma. Additional clues as to the likely age of the lignite are provided by compound-specific stable carbon isotope analyses of the leaf wax lipids. These are approximately 8‰ enriched relative to typical C3 vegetation leaf waxes, and imply a potential contribution from C4 vegetation. From this, an age post-dating the Oligocene may be inferred, and in conjunction with the site’s geomorphic setting, an age post dating the middle Miocene is considered plausible. This is markedly younger than previous (Eocene) age estimates for the Knynsa Formation.

The complex geomorphology of South Africa’s southern Cape coastal belt comprises Gondwana components and a suite of Quaternary sedimentary deposits, superimposed on the older landscape. Of these, the Wilderness aeolianites have previously been reported. This paper is the second of two which focus on the inland coversands. It has a three-fold purpose. Firstly, it provides new information on the sedimentology and geomorphic context of the coversands. Secondly, it suggests a temporal setting for the emplacement of the coversands. Thirdly, the relationship between the coversands, landscape evolution, the Wilderness aeolianites, and the potential of the coversands to serve as indicators of environmental change are examined. The description is preceded by a synopsis of the development of the southern Cape coastal belt. The gross geomorphology of the region was well established by the Middle Pleistocene, but that landscape has been modified since then, and into the Holocene, by sea level and climatic fluctuations. Evidence for southern Cape Quaternary sand deposits predating MIS 5 is only now emerging. The coversands examined in this paper are demonstrated to be both temporally and spatially discrete from the younger coastal aeolianite deposits. A Middle Pleistocene age is tentatively ascribed to the coversands.