Establishing a Bayesian approach to determining cosmogenic nuclide reference production rates using He-3

Cosmogenic 3He is an ideal test-bed for our Bayesian approach. It has the most calibration sites of the commonly measured cosmogenic nuclides, and there is evidence for the effect of erosion on some of the sites. Our approach largely reconciles previous discrepancies between sites of widely varying age, even at latitudes where geomagnetic effects are significant. With the canonical Lal/Stone scaling scheme, we derive a global sea level high latitude 3He production rate of 118 ± 2 atoms g−1 yr−1 when considering olivine and pyroxene together. Using the Lifton-Sato-Dunai scaling scheme yields a similar rate of 121 ± 2 atoms g−1 yr−1. Uncertainties associated with these values are improved over previous studies, due to both reduced scatter among the sites and an approach to combining sites which deemphasizes outliers.