A New Sample Preparation System for Micro-14C Dating of Glacier Ice with a First Application to a High Alpine Ice Core from Colle Gnifetti (Switzerland)

• DOI: 10.1017/rdc.2017.99
• Publication Date: 2017-11-08T10:35:34Z
• Authors: Helene Hoffmann; Susanne Preunkert; Michel Legrand; David Leinfelder; Pascal Bohleber; Ronny Friedrich; Dietmar Wagenbach
• Keywords: Ice core; Firn; Radiometric dating; Accelerator mass spectrometry

Abstract Radiometric dating of glacier ice is an essential tool where stratigraphic methods cannot be applied. This study focuses on Alpine and presents a new sample preparation system for samples via radiocarbon ( 14 C) the microscopic particulate organic carbon (POC) fraction incorporated in matrix. An adaptable, low-cost inline filtration-oxidation-unit (REFILOX) has been developed, which first time unifies all steps from filtration to CO 2 quantification one closed setup. A systematic C investigation modern European aerosol revealed that POC combustion temperature 340°C provides best representation real age. very low process blank maximally 0.3±0.1 µgC now enables high samples, concentrations are generally (typically 10–50 µgC/kg), mass range 300–500 g. In successful application, method was used obtain age constraints core cold, firn saddle Colle Gnifetti (Switzerland). Analysis bottom sections basal 4171–3923 cal yr BP but also so far enigmatic discontinuity age-depth relationship.