Exposure age calculator
Here the exposure age calculator used to recalculate exposure ages can be downloaded. The calculator comprises a set of scripts for Octave/Matlab that can be used to calculate 10Be/26Al/14C exposure ages. The code is mainly based on the CRONUS calculator (Balco et al. 2008) and the LSD production rate scaling (Lifton et al. 2014). In addition to the exposure age calculator (expage.m), there are also scripts for calculating erosion rates (erosion.m), burial durations (burial.m), depth profile exposure ages (depthcalc.m + depthcalcET.m), glacial erosion (glacialE.m), and for calibration of reference 10Be and 26Al production rates (prodrate.m).
Main characteristics of the calculator:
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Numerical integration over time of 10Be/26Al/14C production adjusted for sample thickness, topographic shielding, 10Be/26Al/14C decay, and erosion.
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Nuclide-specific LSD spallation and muon production rate scaling based on simulated cosmic ray fluxes (
Lifton et al. 2014).
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Time-dependent spallation production rate with reference 10Be/26Al/14C production rates based on global average from calibration studies published 2009-2026.
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Adjustment of the time-dependent production rate to the sampling year (assuming a constant production since 2010).
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Atmospheric pressure based on sample elevation and ERA-40 re-analysis dataset, Antarctica best-fit interpolation, or given directly.
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Attenuation length for calculating the spallation production rate adjustments for sample thickness and erosion rate interpolated from atmospheric pressure and cutoff rigidity (
Marrero et al. 2016).
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Calculator log file: calc-log.txt
Code in github: github.com/expage/expage-calculator
DOI: 10.5281/zenodo.23351693
