The cosmogenic 21Ne production rate in quartz evaluated on a large set of existing 21Ne-10Be data

Based on a compilation of published combined 10Be and 21Ne cosmogenic nuclide data sets from quartz samples obtained at ETH Zürich we assess the 21Ne/10Be (P21/P10) production rate ratio with the goal to determine the 21Ne production rate (P21) in quartz. A variety of sliding “erosion islands” in a 21Ne/10Be versus 10Be diagram were evaluated to find the one that fits the data best, which in turn yields the most probable P21 if the 10Be production rate is known. The approach minimizes the influence of samples with a complex exposure history.A best-fit value for P21/P10sp (sp - the 10Be fraction being produced by spallation, as opposed to production by muons) of 4.23 ± 0.17 is obtained for a 10Be half-life of 1.39 Ma. Adopting a P10sp value in quartz of 4.41 ± 0.52 at g−1 yr−1 this yields a P21 of 18.7 ± 2.3 at g−1 yr−1. It is possible that 2% of the 21Ne is produced by fast muons.

Research Highlights► Evaluating the 21Ne cosmogenic nuclide production rate by 10Be-21Ne ratios. ► Using a novel approach of "sliding 10Be-21Ne erosion island plots". ► The new 21Ne production rate is 18.7 ± 2.3 at g−1 yr−1 for a large ETH Zürich data set.