R: Model dose rate evolution in carbonate-rich samples

model_DoseRate {RCarb}

R Documentation

Model dose rate evolution in carbonate-rich samples

Description

This function models the dose rate evolution in carbonate enrich environments. For the calculation internal functions are called.

Usage

model_DoseRate(
  data,
  DR_conv_factors = NULL,
  length_step = 1L,
  max_time = 500L,
  n.MC = 100,
  method_control = list(),
  txtProgressBar = TRUE,
  verbose = TRUE,
  plot = TRUE,
  par_local = TRUE,
  ...
)

Arguments

`data`	data.frame (required): input data following the structure given in the example data set `data(Example_Data)`. The input data.frame should have at least one row (i.e. values for one sample). For multiple rows the function is automatically re-called.
`DR_conv_factors`	character (optional): applied dose rate conversion factors, allowed input values are `"Carb2007"`, `"Adamiec_Aitken_1998"`, `"Guerin_et_al_2011"`, `"Liritzis_et_al_2013"`. `NULL` triggers the default, which is `"Carb2007"`
`length_step`	numeric (with default): step length used for the calculation
`max_time`	numeric (with default): maximum temporal search range
`n.MC`	numeric (with default): number of Monte Carlo runs used for the error calculation
`method_control`	(optional): additional arguments that can be provided to the control the the modelling. See details for further information.
`txtProgressBar`	logical (with default): enables/disables the `txtProgressBar` for the MC runs
`verbose`	logical (with default): enables/disables verbose mode
`plot`	logical (with default): enables/disables plot output
`par_local`	logical (with default): enables/disable local par settings, If set to `FALSE` all global par settings are accepted.
`...`	further arguments passed to the underlying plot functions, see also details for further information. Supported standard arguments are `mfrow`, `xlim`, `xlab`.

Details

This function is the starting point for the dose rate modelling for carbonate enrich environments. It provides basically the same functionality as the original version of 'Carb', i.e. you should be also aware of the limitations of this modelling approach. In particular: The model assumes a linear carbonate mass increase due to post-depositional processes. Please read the references cited blow.

Uncertainty estimation

For estimating the uncertainties, Monte-Carlo (MC) simulation runs are used. For very small values (close to 0) this can, however, lead to edge effects (similar in 'Carb') since values below 0 are set to 0.

Value

The function returns numerical and graphical output

———————————–
⁠[ NUMERICAL OUTPUT ]⁠
———————————–

A data.frame which is the combination of the input and values calculated by this function.

———————————–
⁠[ GRAPHICAL OUTPUT ]⁠
———————————–

Upper plot: Dose rate evolution over time backwards. The solid black line is the calculation output, the grey shaded area indicates the 2-sigma error margins. The dashed blue line is an indicator of the quality of the error estimations based on Monte Carlo (MC) runs.The closer it follows the black line, the more reliable are the given error margins.

Lower plot: Totally absorbed dose over time. The plot is an representation of the 'new' age based on the carbonate modelling.

Function version

0.2.1

How to cite

Kreutzer, S., 2022. model_DoseRate(): Model dose rate evolution in carbonate-rich samples. Function version 0.2.1. In: Kreutzer, S., Nathan, R.P., Mauz, B., 2022. RCarb: Dose Rate Modelling of Carbonate-Rich Samples . R package version 0.1.6. https://r-lum.github.io/RCarb/

Author(s)

Sebastian Kreutzer, Institute of Geography, Heidelberg University (Germany); based on 'MATLAB' code given in file Carb_2007a.m of Carb

References

Mauz, B., Hoffmann, D., 2014. What to do when carbonate replaced water: Carb, the model for estimating the dose rate of carbonate-rich samples. Ancient TL 32, 24-32. http://ancienttl.org/ATL_32-2_2014/ATL_32-2_Mauz_p24-32.pdf

Nathan, R.P., Mauz, B., 2008. On the dose-rate estimate of carbonate-rich sediments for trapped charge dating. Radiation Measurements 43, 14-25. doi:10.1016/j.radmeas.2007.12.012

Further reading

Nathan, R.P., 2010. Numerical modelling of environmental dose rate and its application to trapped-charge dating. DPhil thesis, St Hugh's College, Oxford. https://ora.ox.ac.uk/objects/ora:6421

Zimmerman, D.W., 1971. Thermoluminescent dating using fine grains from pottery. Archaeometry 13, 29–52.doi:10.1111/j.1475-4754.1971.tb00028.x

Examples

##load example data
data("Example_Data", envir = environment())

##run the function for one sample from
##the dataset
model_DoseRate(
data = Example_Data[14,],
n.MC = 2,
txtProgressBar = FALSE
)

[Package RCarb version 0.1.6 Index]