Processes noble gas mass spectrometer data to determine the isotopic composition of argon (comprised of Ar36, Ar37, Ar38, Ar39 and Ar40) released from neutron-irradiated potassium-bearing minerals. Then uses these compositions to calculate precise and accurate geochronological ages for multiple samples as well as the covariances between them. Error propagation is done in matrix form, which jointly treats all samples and all isotopes simultaneously at every step of the data reduction process. Includes methods for regression of the time-resolved mass spectrometer signals to t=0 ('time zero') for both single- and multi-collector instruments, blank correction, mass fractionation correction, detector intercalibration, decay corrections, interference corrections, interpolation of the irradiation parameter between neutron fluence monitors, and (weighted mean) age calculation. All operations are performed on the logs of the ratios between the different argon isotopes so as to properly treat them as 'compositional data', sensu Aitchison [1986, The Statistics of Compositional Data, Chapman and Hall].

Author | Pieter Vermeesch [aut, cre] |

Date of publication | 2015-08-26 23:00:14 |

Maintainer | Pieter Vermeesch <p.vermeesch@ucl.ac.uk> |

License | GPL-2 |

Version | 0.2 |

**average:** Calculate the arithmetic mean

**averagebyday:** Average all the data collected on the same day.

**blankcorr:** Apply a blank correction

**blankcorrected:** The 'blankcorrected' class

**calibration:** Detector calibration

**clcorrection:** Cl-interference correction

**concat:** Merge a list of logratio data

**decaycorrection:** Correct for radioactive decay occurred since irradiation

**fitlogratios:** Extrapolation to 'time zero'

**fractionation:** Compute the mass fractionation correction

**get4039:** Calculate the 40Ar*/39ArK-ratios

**getages:** Calculate 40Ar/39Ar ages

**getJfactors:** Calculate the irradiation parameter ('J factor')

**getmasses:** Select a subset of isotopes from a dataset

**interference:** define the interference corrections

**loaddata:** Load mass spectrometer data

**loadirradiations:** Load the irradiation schedule

**logratios:** The 'logratios' class

**massfractionation:** Apply the mass fractionation correction

**Melbourne:** An example dataset

**newredux:** Create a new 'redux' object

**param:** Set or get Ar-Ar_Redux parameters

**PHdata:** The 'PHdata' class

**plot:** Plot a time resolved mass spectrometry signal

**plotcorr:** Plot a matrix with correlation coefficients

**process:** Process logratio data and calculate 40Ar/39Ar ages

**read:** Read mass spectrometer data

**redux:** The 'redux' class

**results:** The 'results' class

**subset:** Select a subset of some data

**summary:** Summary table

**timeresolved:** The 'timeresolved' class

**weightedmean:** Calculate the weighted mean age

ArArRedux

ArArRedux/inst

ArArRedux/inst/K-glass.csv

ArArRedux/inst/Calibration.csv

ArArRedux/inst/Samples.csv

ArArRedux/inst/AirH1.csv

ArArRedux/inst/irradiations.csv

ArArRedux/inst/Ca-salt.csv

ArArRedux/inst/AirL2.csv

ArArRedux/NAMESPACE

ArArRedux/data

ArArRedux/data/Melbourne.rda

ArArRedux/R

ArArRedux/R/ArArRedux.R
ArArRedux/R/documentation.R
ArArRedux/MD5

ArArRedux/DESCRIPTION

ArArRedux/man

ArArRedux/man/massfractionation.Rd
ArArRedux/man/concat.Rd
ArArRedux/man/fractionation.Rd
ArArRedux/man/getmasses.Rd
ArArRedux/man/getJfactors.Rd
ArArRedux/man/decaycorrection.Rd
ArArRedux/man/param.Rd
ArArRedux/man/fitlogratios.Rd
ArArRedux/man/interference.Rd
ArArRedux/man/averagebyday.Rd
ArArRedux/man/get4039.Rd
ArArRedux/man/Melbourne.Rd
ArArRedux/man/calibration.Rd
ArArRedux/man/loaddata.Rd
ArArRedux/man/blankcorrected.Rd
ArArRedux/man/results.Rd
ArArRedux/man/logratios.Rd
ArArRedux/man/blankcorr.Rd
ArArRedux/man/redux.Rd
ArArRedux/man/read.Rd
ArArRedux/man/plotcorr.Rd
ArArRedux/man/getages.Rd
ArArRedux/man/process.Rd
ArArRedux/man/PHdata.Rd
ArArRedux/man/average.Rd
ArArRedux/man/clcorrection.Rd
ArArRedux/man/plot.Rd
ArArRedux/man/subset.Rd
ArArRedux/man/loadirradiations.Rd
ArArRedux/man/summary.Rd
ArArRedux/man/timeresolved.Rd
ArArRedux/man/newredux.Rd
ArArRedux/man/weightedmean.Rd
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