Assessing Assemblage Integrity and Temporal Associations in Three Sand Bodies on the Cumberland Plain, Sydney

Abstract

Archaeological investigations of sand bodies on the Cumberland Plain in Sydney have reported Pleistocene dates for occupation, however debate over the suspected impact of bioturbation on assemblage integrity raised questions regarding the reliability of these age estimates. Analysis of three assemblages from these sand bodies was structured to address a series of research questions involving the age and depositional context of this archaeological material. A range of analytical methods were employed to investigate the impact of site formation processes on assemblage integrity. These impacts include both the transformation of individual artefacts and redistribution of assemblage components from syn-depositional and post-depositional processes. A 'whole of assemblage' approach provided the opportunity to utilise 'waste' material, such as heat shatter, frequently ignored or discarded by archaeologists. Identification of heat induced fractures assisted not only with estimates of artefact breakage rates and the identification of fire use behaviour, but also provided samples for luminescence dating to obtain age determinations for these burning events. Raw material analysis, refitted artefact sequences and conjoined non-artefactual pieces provided evidence of a range of cultural activities as well as contributing to spatial analysis and assessments of displacement. The validity and timeliness of this study are reinforced by an examination of specific research questions raised in recent archaeological studies in the Sydney region and adjacent areas. Although this thesis does not attempt to support or refute any claims of antiquity or propose any new regional chronologies for archaeological sites outside the Sydney Basin, the findings do contribute to the debate regarding direct temporal association between stone artefacts and dated sediments in other sites. The results indicate that site formation processes can have a significant impact on the accuracy of dating cultural remains using age estimates obtained using luminescence procedures on sediments.