MESOZOIC DEEP WEATHERING AND EROSION - AN EXAMPLE FROM WILSONS PROMONTORY, AUSTRALIA

Deep weathering profiles and associated landforms are well known, but several aspects of genesis and age are not agreed. This paper reports tests of alternative hypotheses in the Wilsons Promontory area, southe rn Victoria, Australia. Wilsons Promontory is an area of Devonian gran ite. The granite had been unroofed by the Permian, and a palaeoplain e xisted in Trias-Jura times, below which the granite continued to be de eply weathered to the Lower Cretaceous. The resultant profile was at l east 300 m thick, and consisted of regular zones. The area was faulted and uplifted in mid-Cretaceous times, since when it has experienced e rosional stripping. This supports hypotheses suggesting that landscape evolution in areas of deep weathering can occur with a single period of deep weathering followed by a distinct stage of regolith stripping.