A Review of Quaternary Aeolian Deposition in Central and Southeastern Australia

摘要

During the period 35-55 ka, the continental dunefields of Australia were mostly stable, gypsum dunes were formed at the playa margins of central Australia, sandy lunette dunes were formed along lake margins in southeastern Australia; and there was no dust (parna) deposition. During the period 16-25ka, the continental dunefields were reactivated, dust (parna) deposited across southeastern Australia and in the Tasman Sea, formation of sandy lunettes was replaced by clay lunettes as high lake levels fell significantly, and there was no gypsum dune formation in central Australia. The reactivation of the dunefields during Holocene and the last glacial maximum (25-16 ka) limited preservation of older dunes. Severe deflation resulted in major hiatus in playa sediment sequences and significantly lowered the playa surfaces. The prevailing deflation in more arid zones during drier periods produced large quantity of dust which was transported and deposited in the relatively moist southeastern Australia and in the Tasman Sea. These dust deposits on land (parna) and in the sea may provide one of the best records of the aeolian activities of the continent.