Elemental δ¹³C at Allen's Cave, Nullarbor Plain, Australia: Assessing post-depositional disturbance and reconstructing past environments

The degree to which post-depositional disturbance can be assessed in archaeological sequences is critical for the development of robust chronologies for such deposits. A common approach is the identification of conjoined artefacts distributed through the sequence as a measure of disturbance following deposition, although this method is relatively labour intensive and does not provide a continuous record of disturbance through the entire sequence. Here we present δ¹³C values for different size fractions (<125 and >125 μm) of chemically resistant charcoal distributed through a sedimentary profile at Allen's Cave, South Australia. The curves generated from both size fractions parallel one another, indicating minimal disturbance through the entire profile and providing greater confidence in the luminescence and radiocarbon chronologies reported previously for the site. In addition, the elemental δ¹³C values provide an indication of greater aridity (compared with present) persisting in this area from ca. 45 to 12 ka, consistent with other proxy records. The onset of the Holocene is marked by a shift to wetter conditions, probably as a result of post-glacial marine transgression and closer proximity to the coastline.