Zeta calibration coefficient for LA-ICP-MS fission track dating

Calibrate the ICP-session zeta factor using the number of spontaneous tracks, the area over which these were counted and one ore more U/Ca, U/Si or U-concentration measurements (in ppm) and their analytical uncertainties.

Usage

zeta_ICP(
  x,
  spotsize = 40,
  mineral = c("zircon", "apatite"),
  standard = c("Dur", "FCT"),
  tst,
  lambda = pkg.env$lambda[1],
  g = pkg.env$g,
  ...
)

Arguments

x: data.frame containing counts of spontaneous tracks, U concentrations, and the uncertainties of U concentrations
spotsize: the laser ablation spot size (diameter in micrometer)
mineral: Mineral of the standard, one of 'zircon' or 'apatite'
standard: Name of the standard, one of 'Dur' or 'FCT'
tst: (optional) two-column vector giving the true age and its standard error. overrides mineral and standard
lambda: (optional) decay constant
g: (optional) geometry factor (default: 0.5)
...: additional arguments

Value

list containing: two-element vector with the session zeta and its standard error

References

Hasebe, N., Carter, A., Hurford, A.J., Arai, S., 2009. The effect of chemical etching on LA-ICP-MS analysis in determining uranium concentration for fission-track chronometry. Geol. Soc. Lond. Spec. Publ. 324 (1), 37--46. doi:10.1144/SP324.3

Examples

data("standard")
zeta_ICP(standard, spotsize = 40, mineral = "apatite", standard = "Dur")
#> $data
#> # A tibble: 34 × 6
#>    Grain     Ns UO           U       sU comments
#>    <chr>  <dbl> <lgl>    <dbl>    <dbl> <lgl>   
#>  1 DUR-1      4 NA    0.000496 0.000016 NA      
#>  2 DUR-2      3 NA    0.00052  0.000018 NA      
#>  3 DUR-3      1 NA    0.000476 0.000014 NA      
#>  4 DUR-4      3 NA    0.000465 0.000014 NA      
#>  5 DUR-5      6 NA    0.000471 0.000012 NA      
#>  6 DUR-6      3 NA    0.000469 0.000014 NA      
#>  7 DUR-7      4 NA    0.000471 0.000013 NA      
#>  8 DUR-8      2 NA    0.000495 0.000016 NA      
#>  9 DUR-9      4 NA    0.000477 0.000018 NA      
#> 10 DUR-10     2 NA    0.000461 0.000015 NA      
#> # ℹ 24 more rows
#> 
#> $results
#>         rhos       zeta
#> 1  318309.89 0.09822082
#> 2  238732.41 0.13729792
#> 3   79577.47 0.37704122
#> 4  238732.41 0.12277603
#> 5  477464.83 0.06218012
#> 6  238732.41 0.12383217
#> 7  318309.89 0.09327018
#> 8  159154.94 0.19604559
#> 9  318309.89 0.09445833
#> 10 159154.94 0.18257984
#> 11 238732.41 0.12013568
#> 12 159154.94 0.17069828
#> 13 159154.94 0.17307460
#> 14 238732.41 0.11960761
#> 15 397887.36 0.07176457
#> 16 238732.41 0.11142255
#> 17 557042.30 0.04933673
#> 18 238732.41 0.12198393
#> 19 318309.89 0.09406228
#> 20 238732.41 0.12673655
#> 21 238732.41 0.17188644
#> 22  79577.47 0.48951991
#> 23  79577.47 0.47130153
#> 24 238732.41 0.15683648
#> 25 318309.89 0.09267610
#> 26  79577.47 0.36436757
#> 27 397887.36 0.07667561
#> 28 477464.83 0.05835162
#> 29 318309.89 0.09564649
#> 30 238732.41 0.12832075
#> 31 238732.41 0.12383217
#> 32 238732.41 0.12515234
#> 33 159154.94 0.18178773
#> 34 318309.89 0.08752743
#> 
#> $zeta
#>       zeta        std 
#> 0.11831145 0.01182395 
#>