Local Beryllium-10 production rate for the mid-elevation mountainous regions in Central Europe, deduced from a multi-method study of moraines and lake sediments in the Black Forest.

Autor: Hofmann, Felix Martin, Rambeau, Claire, Gegg, Lukas, Schulz, Melanie, Steiner, Martin, Fülling, Alexander, Léanni, Laëtitia, Preusser, Frank
Předmět:
Zdroj: Geochronology; 1/9/2024, p1-41, 41p
Abstrakt: Beryllium-10 cosmic-ray (CRE) exposure dating has revolutionised our understanding of glacier fluctuations around the globe. A key prerequisite for the successful application of this dating method is a thorough understanding of local production rates of in-situ accumulated 10Be, usually inferred from independently dated regional reference sites. For the mid-elevation (Variscan) mountain ranges of central Europe, no production rate reference site has been available so far. We fill this gap by determining in-situ 10Be concentrations in large boulders on moraines and by applying radiocarbon and luminescence dating to stratigraphically younger lake sediments in the southern Black Forest, SW Germany. The dating methods yielded concordant results and, based on age-depth modelling with 14C ages, we deduced a local 10Be production rate. The resulting Black Forest (BF) production rate is ~11 % lower than both those at the nearest reference site in the Alps and the canonical global 10Be production rate. A stronger weathering and snow cover bias and a higher impact of soil, moss and shrub cover at the stud site likely explain this discrepancy. Due to its internal robustness, we suggest applying the BF production rate in future CRE dating studies in Central Europe and for revising existing age estimates which will have crucial implications for understanding past atmospheric circulation patterns. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index