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Table 3 Cosmogenic nuclide data and 10Be exposure ages

From: Post-depositional impacts on ‘Findlinge’ (erratic boulders) and their implications for surface-exposure dating

Sample name Quartz dissolved (g) 9Be spike (mg) Measured 10Be/9Be ×10−14 Full process blank ratio (10Be/9Be) ×10−14 10Be (104 atoms/g) Apparent exposure age (ka) Exposure age (ka) erosion corrected (ε = 3.0 mm/ka)
MOE-1 35.5032 0.2035 33.27 ± 1.03 2.20 ± 0.17 11.90 ± 0.40 13.6 ± 0.5 (1.2)
MOE-2 35.9433 0.2033 47.95 ± 2.01 2.20 ± 0.17 17.29 ± 0.76 18.1 ± 0.8 (1.7) 19.0 ± 0.9 (1.9)
MOE-3 100.6804 0.2547 42.96 ± 2.06 0.30 ± 0.05 7.21 ± 0.35 7.5 ± 0.4 (0.7)
  1. Reported ratios and concentrations are referenced to 07KNSTD (Kubik and Christl 2010). AMS measurement errors are at 1σ level, including the statistical (counting) error and the error due to normalization of standards and blanks. Exposure ages are calculated with the CRONUS-Earth exposure age calculator (http://hess.ess.washington.edu/math/; v. 2.2; Balco et al. 2008 and update from v. 2.1 to v. 2.2 published by Balco in October 2009) and time dependent Lal (1991)/Stone (2000) scaling model. Exposure ages are corrected for dip of rock surface, shielding of surrounding topography, and sample thickness, as explained in the text; the uncertainties reported in parentheses also include the production rate error. A half-live of 1.39 Ma for 10Be (Korschinek et al. 2010; Chmeleff et al. 2010) is used for the age calculations