MINIMALLY DESTRUCTIVE LITHIC SOURCE TRACING UTILIZING pXRF GEOCHEMICAL ANALYSIS IN CONJUNCTION WITH INITIAL Nd ISOTOPIC RATIOS

This study investigates the geochemical characterization and source tracing of lithic materials using a cost-effective and reliable approach that integrates portable X-ray fluorescence (pXRF) and neodymium (Nd) isotope geochemistry. This study builds on the foundational work of Steponaitis and colleagues (2006) at the Research Laboratories of Archaeology, University of North Carolina at Chapel Hill, to demonstrate a minimally to non-destructive method for tracing the movements of indigenous groups in the Carolinas and Virginia who exploited silicic rhyodacitic outcrops within the Carolina Terrane (also referred to as the Carolina Slate Belt).Lithic artifacts and quarry samples, derived from 500–630 Ma island arc systems in the Carolina Terrane, were examined to trace their provenance. Comparisons between pXRF and ICP-MS results, alongside evaluations of elemental resilience to time and weathering, highlighted key analytes—Ga/Al, Ga/Si, Rb/K, and Ga/Y—that effectively predict artifact provenance. These analytes also align with previous studies, further validating their use.Nd isotope geochemistry was employed to compare unweathered and weathered samples of the same rock fragments, assessing the reliability of altered rock for sourcing. Despite variations in Sm and Nd concentrations and Sm/Nd ratios due to weathering, initial Nd isotopic ratios (143Nd/144Nd(550Ma)) remained consistent within uncertainty. This confirms the robustness of the Sm/Nd isotopic system and supports minimally invasive surface sampling as a viable diagnostic tool for differentiating magmatic systems without compromising the archaeological record.The findings traced artifacts to specific source zones across the Piedmont and highlighted the human role in the movement of natural resources across landscapes, deepening our understanding of indigenous mobility and resource use.