LATE PLEISTOCENE RIVER MORPHOLOGICAL CHANGE, SOUTHEASTERN AUSTRALIA - THE CONUNDRUM OF SINUOUS CHANNELS DURING THE LAST GLACIAL MAXIMUM

Early and mid-glacial palaeochannels and the present post glacial-maximum channel form in southeastern Australia reflect catchment climatic and vegetation states. Palaeochannels that span the Last Glacial Maximum, however, maintain a sinuous form in spite of conditions considered to be conducive to a straighter morphology. Increased deposition of aeolian clay and silt in catchments and their remobilisation in unstable periglacial and deforested conditions may have resulted in a high suspended load in streams at this time. Deposition of this material on banks and bars in low winter flows and by aggregation in saline waters may have stabilised channel boundaries, causing development of the sinuous channel form.