Luminescence dating at the archaeological and human burial site at Roonka, South Australia

Roonka, the Aboriginal habitation and burial site on the River Murray, South Australia, was excavated from 1968 to 1983. In 1983, thermoluminescence (TL) ages were obtained for several fireplaces at the East Bank site. Sandy dune sediments collected from East Bank were also analysed using traditional TL methods and ages were found at depths down to the base at 2.6 m. Now, 20 years on, with optical dating methods well established, it seemed instructive to repeat the measurements using new techniques, specifically the single aliquot regeneration dose protocol. This has provided confirmation of the TL ages and provided an age framework for both the archaeological and geological aspects of Roonka. The ages confirm the archaeological description of the structure of the dune and show that only the top 20% is the Holocene Bunyip formation. The lower part is assigned to the Woorinen Formation, formed during and after the last glacial maximum. Burials at East Bank took place between about 16 and 20 ka, substantially earlier than those on the Roonka Flat, but consistent with the earliest evidence of occupation on the Flat. They are one of the very few securely dated Pleistocene burials in Australia. Whether the individuals were gracile or robust is not known.