Geochronology and Isotope Geochemistry

Probability Density Function and Histogram for data with uncertainties

Import data from Excel spreadsheets and calculate the probability density function for the data and the histogram representing the ages. May be used for large data sets which might not be handled by other Excel-based packages. The pdf curve and histogram values may be exported for publication-quality graphing in other programs. Now also calculates stratigraphic, 'view from above' probability plots for multiple samples or lithostratigraphic units to illustrate detrital zircon ages relative to stratigraphic age and cumulative probability curves. The latter are classified and colour coded according to the scheme introduced by Cawood et al. (2012). Users should choose either the 32 bit version of the software or a 64 bit version (default link above).

Extract 'raw' data from spreadsheets for DateView 64 bit

Import data from Excel spreadsheets for use in DateView database. Collate and check data ready for import before submitting a copy of a local database file to the database administrator for uploading to DateView.

Geodate isotope software

Isotope regression and calculation software. Perform a variety of regression calculations, determine model ages, initial ratios, epsilon or gamma values, weighted averages. Convert zircon data (including error correlations) from Wetherill to Tera-Wasserburg formats. Data may be read from custom GeoDate files or imported from Excel spreadsheets. This 2018 version 4 program has been modified to be suitable for use with Windows 10 operating systems. Most recent update of installation file posted 2024/01/19. Documentation for this software is available as a pdf.

U-Pb isotope open system modelling

Forward model the effects of open system behaviour in two-stage U-Th-Pb isotope systems. Users may select a range in 238U/204Pb and 232Th/204Pb ratios at the time a system is disturbed so as to investigate changes graphically. Users should choose either the 32 bit version of the software or the 64 bit version (default link above).

DateView desktop geochronology database system

Software for use in a desktop PC computer environment. Users may compile geochronological information utilising a user-customisable database system which has an easy user interface. The capabilities of this package have been described in Eglington (2004) Computers and Geosciences, vol. 30, p847-858. The download provides an empty database (it does not include data previously captured by the author). These data are now available from the web version of DateView, which is available from the Database page of this site. Documentation for this software is available as a pdf.

Geochemistry and Petrology

CIPW, meso- and kata-norm calculator

Calculates CIPW, Meso- and kata-norms based on data imported from Excel spreadsheets. In addition to providing normative mineral compositions, the program calculates a variety of geochemical projections and ratios often used during petrological investigations. All calculated values may be exported to Excel spreadsheets for use in other programs or for graphing. Users should choose either the 32 bit version of the software or the 64 bit version (default link above).

Lithostratigraphy

South African lithostratigraphic database

User-friendly interface and database of South African lithostratigraphic units. Formations compiled in this database are from the South African Council for Geoscience's corporate database and include all formally recognised stratigraphic units. Documentation for this software is available as a pdf. The contents of this desktop system are now available on-line using the program StratDB, which can be found on the database page of this site.

Geostatistics

Multivariate statistical analysis software

Multivariate statistical analysis software for use in exploratory data analysis. Data are read in from Excel spreadsheets. Techniques incorporated in the package are: Simultaneous R- and Q-mode component analysis; Principal component analysis; Correspondence analysis; Discriminant analysis. Data may be transformed using log-normal or centered log-ratio approaches prior to analysis. Various non-parametric statistics are calculated and variables are portrayed as histograms, sequence plots, quantile-quantile plots and box plots. Plots of sample locality (X-Y-Z) may be produced with symbols coded to EDA box plot classifications in order to assess the spatial distribution of outliers. This version of the software is limited to 30 variables and 400 samples but users may contact Bruce Eglington to obtain a version capable of processing larger matrices.

Compare two curves with equivalent x axes

Software facilitates the comparison of two curves which have equivalent x axis parameters. For instance, one may wish to compare two probability density curves derived from geochronological investigations or compare two isotope proxy curves for a given time period. this software utilises non-parametric geostatistical techniques for the comparison. This is an alpha test version of the software.

Compute weighted time variation curves

Software calculates weighted and standard moving averages for a data series. The weighted moving averages are based on weighted splines curve fitting which takes analytical uncertainties into account. The degree os smoothing is user-customisable. Standard moving averages may also be caclulated but are known to distort the location of peaks in time series data as a function of the number of points included in the moving average. This distortion is not present when using the weighted moving average technique.

Mass spectrometer control, data reduction and diagnostics

Graphical view of amplifier gain information for Thermo Triton and Neptune instruments

Software for use in a desktop PC computer environment. Users should first convert the GainHistory.log file from either Triton or Neptune instruments into MicroSoft Excel format (just open the original file and save as an Excel file). This file is then imported into the GainLog program and users may check out graphical views of the gain variation on different amplifiers through time.