Luminescence dating of coastal landforms in Australia: A review, database and geomorphic significance

Luminescence dating (Thermoluminescence – TL and Optically Stimulated Luminescence – OSL) has advanced our understanding of the age of a wide variety of coastal landforms. Early studies around the Australian coast focused testing TL and OSL dating approaches against existing chronological data and established principals for typical sampling strategies in a variety of depositional environments. Luminescence dating has supported studies of 1) transgressive dunes, including the large sand islands of southeast Queensland, 2) prograded barriers comprising both the coarse-grained ridges of Queensland and the foredune ridges of temperate Australia, 3) the uplifted coastal barriers of the Coorong Coastal Plain, 4) chenier ridges, 5) clifftop dunes, 6) terrestrial dunes developed along the coast, 7) aeolianite in the regions dominated by cool-water carbonates, 8) tsunami and other high-energy deposits such as cyclone-induced washover fans, and 9) subaqueous deposits such as shoreface, deltaic and estuarine sedimentary deposits. Synthesising the luminescence chronology in these settings emphasises the substantial contribution of luminescence dating to our understanding of Quaternary landscape evolution and coastal geomorphology in Australia. In these diverse environmental settings, the luminescence properties of Australian coastal sediment have enabled ages to be determined from <50 a to >500 ka. The spatial and temporal changes in environmental dose rate facilitated by this review reveals important regional patterns in relationship to geological and geomorphic setting. In some cases, dose rate uncertainties and the potential for U-series disequilibria create particular challenges requiring understanding of the depositional context. Future research which aims to refine the luminescence method, fill geographic gaps in our knowledge and investigates comparatively understudied landform types will play an important role in furthering our understanding of Australian coastal landscape evolution.