If two curves need to be 'mixed' to calibrate, e.g. for dates of mixed terrestrial and marine carbon sources, then this function can be used.
mix.curves(proportion = 0.5, cc1 = "3Col_intcal13.14C",
cc2 = "3Col_marine13.14C", name = "mixed.14C", dirname = ".",
offset = c(0, 0))Proportion of the first calibration curve required. e.g., change to proportion=0.7 if cc1 should contribute 70% (and cc2 30%) to the mixed curve.
The first calibration curve to be mixed. Defaults to the northern hemisphere terrestrial curve IntCal13.
The second calibration curve to be mixed. Defaults to the marine curve IntCal13.
Name of the new calibration curve.
Directory where the file will be written. If using the default dirname=".",
the new curve will be saved in current working directory.
Any offset and error to be applied to cc2 (default 0 +- 0).
A file containing the custom-made calibration curve, based on calibration curves cc1 and cc2.
The proportional contribution of each of both calibration curves has to be set.
Blaauw, M. and Christen, J.A., Flexible paleoclimate age-depth models using an autoregressive gamma process. Bayesian Anal. 6 (2011), no. 3, 457--474. https://projecteuclid.org/download/pdf_1/euclid.ba/1339616472