LATE QUATERNARY AEOLIANITES, PALEOSOLS AND DEPOSITIONAL-ENVIRONMENTS ON THE NEPEAN PENINSULA, VICTORIA, AUSTRALIA

The Nepean Peninsula is a bay-mouth bar near Melbourne. It is comprise d of Late Quaternary aeolianites, palaeosols and calcretes. TL dates s how that most of the sands from which the aeolianites developed as mob ile sand dunes were deposited during times of low sea-level towards 47 and 23 ka BP, and others during times of relatively high sea-level to wards 118 ka BP. Aeolian dust mantles were laid down during brief inte rvals when aeolianite formation had ceased. Incipient soil formation a nd minor organic staining of the upper 0.3-0.5 m of the dust mantles p oints to a lull in dune formation and the temporary development of a w idespread plant cover. The dust mantles have TL ages of 118, 57, 54, 5 1 and 47 ka BP, indicating that apart from the 118 ka mantle, most of the deposition was when sea-level was low and the regional climate was drier, windier, colder and under a more continental climatic regime. During times of glacially lower sea level, the coastal climate in this region was not invariably cold, dry and windy but was punctuated by b rief intervals of milder, moister and less windy conditions during whi ch dunes and dust mantles became vegetated and soils began to farm. Ra pid climatic fluctuations were coeval with aeolianite deposition durin g times of very low sea-level.