Waikato samples were pre-treated following standard AMS protocols (UCI KCCAMS, 2011a, b). Following pre-treatment, charcoal (∼2 mm fragments) samples were converted to CO2 in sealed quartz tubes by oxidation at 800°C, using pre-baked CuO in the presence of silver wire to absorb any SOx and NOx produced. Shell (< 3 mm fragments, 35-45 mg) were etched in 0.1M HCl at 80°C to remove ∼45% of the surface. Cleaned shells were then tested for recrystallization by Feigl staining (Friedman, 1959) to ensure either aragonite, or a natural aragonite/calcite distribution was present in the shell (e.g. Nerita sp.). CO2 was collected from shells by reaction with 85% H3PO4. Cryogenically separated CO2 was then reduced to graphite with H2 at 550°C using an iron catalyst. δ 13 C was measured either on a LGR Isotope analyser CCIA-46EP or a Thermos Scientific MAT252 IRMS. Pressed graphite was analysed at the Keck Radiocarbon Dating Laboratory, University of California on a NEC 0.5MV 1.5SDH-2 AMS system (Southon et al., 2004). At ANSTO, after visual inspection for the presence of any powdery, potentially extraneous, calcite deposition shell surfaces were physically cleaned by abrasion of 10-25% of thickness with a Dremel ® tool followed by chemical etching of another 10% with 0.5M HCl for 1-5 minutes under sonication at room temperature (Hua et al., 2001). Feigl

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The re-excavation of Karnatukul (Serpent’s Glen) has provided evidence for the human occupation of the Australian Western Desert to before 47,830 cal. BP (modelled median age). This new sequence is 20,000 years older than the previous known age for occupation at this site. Re-excavation of Karnatukul aimed to contextualise the site’s painted art assemblage. We report on analyses of assemblages of stone artefacts and pigment art, pigment fragments, anthracology, new radiocarbon dates and detailed sediment analyses. Combined these add significantly to our understanding of this earliest occupation of Australia’s Western Desert. The large lithic assemblage of over 25,000 artefacts includes a symmetrical geometric backed artefact dated to 45,570–41,650 cal. BP. The assemblage includes other evidence for hafting technology in its earliest phase of occupation. This research recalibrates the earliest Pleistocene occupation of Australia’s desert core and confirms that people remained in this part of the arid zone during the Last Glacial Maximum. Changes in occupation intensity are demonstrated throughout the sequence: at the late Pleistocene/Holocene transition, the mid-Holocene and then during the last millennium. Karnatukul documents intensive site use with a range of occupation activities and different signalling behaviours during the last 1,000 years. This correlation of rock art and occupation evidence refines our understanding of how Western Desert peoples have inscribed their landscapes in the recent past, while the newly described occupation sequence highlights the dynamic adaptive culture of the first Australians, supporting arguments for their rapid very early migration from the coasts and northern tropics throughout the arid interior of the continent.

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