DOI: 10.6084/m9.figshare.27284775.v1
title: Bayesian Calibration of the 40K Decay Scheme and its implications for 40K-based geochronology

description: FireClay_data_table.xlsx is an excel file with the raw data 40Ar/39Ar single fusion measurements on the Fire Clay tonstein. This data is full reduced and defines the interference corrections used and methodology of the mass discrimination.Final_Bayes_Input_Data.xlsx is an excel file with all input data into the model. This file contains: 238U/206Pb - measured ratios, uncertainties, and MSWD (where available); 235U/207Pb - measured ratios, uncertainties, and MSWD (where available); RX_FCs - measured ratios, uncertainties, and MSWD (where available). File also contains some notes and descriptions of each sample.BayesCal_InputData.ipynb -(Jupyter notebook) Reads in the preliminary file from pathway, modifies and propagates uncertainties using linear matrix algebra and sqrt(mswd) saves final data frame to user defined excel fileRunning_Input_Data Class.ipynb (Jupyter notebook) - Example of how to read in preliminary data and get formatted final input dataset for the model.Uni_delta.xlsx - Excel Spread sheet of delta ages between 235U/2307Pb and 40Ar/39Ar and 238U/2306Pb and 40Ar/39ArUni_Res_Time.xlsx - Excel Spread sheet of residence times for all appropriate samplesUni_U_decay_constants.xlsx - Excel Spread sheet of posterior values and uncertainties for 235U and 238U decay constantsUni_lam.xlsx - Summary of all posterior values for 40K decay scheme<br>Uni_FCs.xlsx - Summary of all posterior values for Fish Canyon sanidine <br>Uni_u238_Xi.xlsx - Summary of all posterior values for age perturbations for each 238U/206Pb age of each sampleUni_u235_Xi.xlsx - Summary of all posterior values for age perturbations for each 235U/207Pb age of each sample<br>Uni_Ar_Xi.xlsx - Summary of all posterior values for age perturbations for each 40Ar/39Ar age of each sample<br>Uni_K40K_samples.xlsx - Summary of all posterior values for 40K/K ratios of each sampleUni_K40K_standards.xlsx - Summary of all posterior values for 40K/K ratio for Fish Canyon sanidine and the 40K/K for the decay constant materialPotassium Isotopic Variability and implications for age.ipynb - Notebook for summary plot of potassium isotopic variability - Figures S8 and S9 in the supplementary material<br>Calibration Comparison Figure.ipynb - Notebook for plotting comparison of Min/Kuiper, Renne et al., and the Bayesian calibrations as a function of age. Figure 3 in the manuscript.<br>Bayesian Calibration Paper Plots.ipynb - Notebook for plotting Figures 1, 2, and 4 in the associated manuscript.Residence time and delta age plots.ipynb - Plots of age perturbation parameter values and residence time - Figures S5 and S6 in the supplementary material. Ar_ages_and_uncertainties (Jupyter notebook) - Notebook for calculating ages and uncertainties given a R-value relationship between the unknown and Fish Canyon sanidine. Covariance between the total decay constant and FCs is included. It is assumed that the the covariance in a measured R-value to both the FCs age and total decay constant is zero. Ages are given for the R-values reported in Table 9 in the manuscript and reported in section 4.5. All ages should agree.<br>BayesCal Comp (Jupyter notebook) - Jupyter notebook containing the entire code for the MCMC algorithm described in the "Bayesian Calibration of the 40K Decay Scheme and its implications for 40K-based geochronology" manuscript. Some plots are given in this note book but, the majority are store as summary excel files to be plotted elsewhere.Potassium Isotopic Variability and implications for age.ipynb - Notebook for plotting and summary of the implications for a calculated 40Ar/39Ar age accounting for the model variance in the 40K/K ratio between samples, FCs neutron fluence monitor, and material used to measure the total decay constant.Residence time and delta age plots.ipynb - Notebook for plotting the output residence times summary and the age-perturbing parameters summary.40K decay constant comparison.ipynb - Notebook for plotting the model estimate 40K decay constant against all other decay constants (Table 1 in the manuscript). Also contains calculation for updating the decay constant for variability in 40K/K.<br>Bayesian Calibration Paper Plots.ipynb - Notebook for reading in the model outputs and plotting Figures 1, 2, and 4 in the manuscript.<br>Calibration Comparison Figure.ipynb - Notebook for comparison of the most widely used calibrations of Min/Kuiper et al. and Renne et al. 2011 with the Bayesian calibration this study.Z-score_comparison.ipynb - Notebook for calculating the Z-scores of the Renne et al. (2011) and Bayesian calibrations ages of ACs, Melilla sample, and FCs with the astronomical age estimates.<br><br>