Radiocarbon simulation fails to support the temporal synchroneity requirement of the Younger Dryas impact hypothesis
Ian Jorgeson, Ryan P. Breslawski, Abigail E. Fisher
Abstract
Abstract Fine-scale temporal processes, such as the synchronous deposition of organic materials, can be challenging to identify using 14 C datasets. While some events, such as volcanic eruptions, leave clear evidence for synchronous deposition, synchroneity is more difficult to establish for other types of events. This has been a source of controversy regarding 14 C dates associated with a hypothesized extraterrestrial impact at the Younger Dryas Boundary (YDB). To address this controversy, we first aggregate 14 C measurements from Northern Hemisphere YDB sites. We also aggregate 14 C measurements associated with a known synchronous event, the Laacher See volcanic eruption. We then use a Monte Carlo simulation to evaluate the magnitude of variability expected in a 14 C dataset associated with a synchronous event. The simulation accounts for measurement error, calibration uncertainty, “old wood” effects, and laboratory measurement biases. The Laacher See 14 C dataset is consistent with expectations of synchroneity generated by the simulation. However, the YDB 14 C dataset is inconsistent with the simulated expectations for synchroneity. These results suggest that a central requirement of the Younger Dryas Impact Hypothesis, synchronous global deposition of a YDB layer, is extremely unlikely, calling into question the Younger Dryas Impact Hypothesis more generally.