C04_09

A Simulation Approach to Quantify the Parameters and Limits of the Radiocarbon Wiggle Match Dating Technique

McDonald L¹, Manning S¹

¹Cornell Tree-ring Laboratory, Ithaca, United States

Worldwide, radiocarbon (¹⁴C) wiggle-match dating is increasingly used to produce high-resolution, ‘near-absolute’, chronologies in a range of different contexts, yet the exact properties and limitations of the technique are not well understood. Here we present the results of extensive and systematic simulations that allow the precision limits of wiggle-match dating to be quantified for different time periods. In this presentation we use the periods 4000-3600 BCE and 1000-1800 CE as case studies. We have also been able to quantify the effect of modeling decisions on precision possible in terms of how many measurements to make, how far apart to space them, and which calibration curve to employ. We find that while recent trends towards large numbers of annually spaced measurements can improve precision, the effect is generally small, except when the dated sequence falls on a plateau in the calibration curve. Finally, we demonstrate that wiggle matching against an unsmoothed record of atmospheric ¹⁴C can provide better precision than wiggle matching against the smoothed IntCal20 or SHCal20 curves. We argue, however, that until intra-hemispheric variation in ¹⁴C is better understood, the hemispheric averages provided by IntCal20 and SHCal20 will be the more appropriate datasets for the majority of wiggle-match applications.