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Quantitative studies of relative dating parameters, including subsurface dolerite weathering rind thickness and weathering front penetration, permit the differentiation of three broad groupings of till deposits in several valleys in north‐central, western, western‐central and south‐western Tasmania. An early cold climatic phase–the Linda Glacial Stage–is recognised on the basis of this weathering evidence which also indicates that there have been at least two more recent Glacial Stages of decreasing severity, termed here the Henty and Margaret Glacial Stages respectively. This three‐fold model bears a striking similarity to that of Lewis (1945) which was rejected nearly three decades ago. However, whereas Lewis' model was founded upon erosional evidence, the present study is based entirely upon depositional and weathering evidence.

During the Late Wisconsin, icecap and outlet glacier systems developed on the West Coast Range and on the Central Plateau ofTasmania. Local cirque and valley glaciers occurred in many other mountain areas of southwestern Tasmania. Criteria are outlined that enable Late Wisconsin and older glacial landforms and deposits to be distinguished . Rad iocarbon dates show Late Wisconsin ice d eveloped after 26-25 ka BP, attained its maximum extent c. 19 ka BP, and disappeared from the highest cirques before 10 ka BP. Important Late Wisconsin age glacial landforms and deposits of the West Coast Range, north-central and south-central Tasmania are described. Late Wisconsin ice was less extensive than ice formed during middle and earlier Pleistocene glaciations. Late Wisconsin snowline altitudes, glaciological conditions and palaeodimatic conditions are outlined.

Part of an extensive ice cap that developed in the Tasmanian Central Highlands during the late Cenozoic discharged southwards via a major outlet glacier that occupied the valley of the Derwent River. At least three and probably five phases of glaciation took place. The first and most extensive glaciation may have been early Pleistocene in age, while the most recent and least extensive occurred during the late Last Glacial Stage. When the ice cover was most extensive, the Derwent Glacier was up to 500 m thick. It may have extended to as low as 230 m above sea level, 70 km downvalley. Diffluent lobes of this glacier spread eastwards to merge with other glaciers in the Nive Valley, southwards into the upper Gordon Valley, and westwards into the upper Franklin and Alma Valleys. The ice masses of west-central Tasmania were mainly of temperate maritime character.