TECHNICAL NOTE Interpretation of Whole-rock Geochemical Data in Igneous Geochemistry: Introducing Geochemical Data Toolkit (GCDkit)

Geochemical Data Toolkit (GCDkit) is a program for handling and recalculation of geochemical data from igneous and metamorphic rocks. It is built using the Windows version of R, which provides a flexible and comprehensive language and environment for data analysis and graphics. GCDkit was designed to eliminate routine and tedious operations involving large collections of whole-rock data and, at the same time, provide access to the wealth of statistical functions built into R. Data management tools include import and export of data files in a number of formats, data editing, searching, grouping and generation of subsets. Included are a variety of calculation and normative schemes, for instance CIPW and Mesonorm, as are the common geochemical graphs (e.g. binary and ternary graphs, Harker plots, spider plots, and several dozens of classification and geotectonic discrimination diagrams). The graphical output is publication ready but can be further retouched if required. The system can be further expanded by means of plug-in modules that provide specialist applications. GCDkit is available as Free Software under the terms of the Free Software Foundation’s GNU General Public License and can be downloaded from http://www. gla.ac.uk/gcdkit. The product is actively maintained and updated to provide additional functionality; Unix/Linux and Mac OS versions are being developed.

[1]  E. C. Grunsky,et al.  R: a data analysis and statistical programming environment-an emerging tool for the geosciences , 2002 .

[2]  Francis Albarède,et al.  Introduction to Geochemical Modeling , 1995 .

[3]  Gary B. Sidder,et al.  PETRO.CALC.PLOT, Microsoft Excel macros to aid petrologic interpretation , 1994 .

[4]  S. Taylor,et al.  Geochemistry of eocene calc-alkaline volcanic rocks from the Kastamonu area, Northern Turkey , 1976 .

[5]  S. Goldstein,et al.  A Sm-Nd isotopic study of atmospheric dusts and particulates from major river systems , 1984 .

[6]  V. Janoušek.  Saturnin , R language script for application of accessory-mineral saturation models in igneous geochemistry , 2006 .

[7]  P. Fort,et al.  A chemical–mineralogical classification of common plutonic rocks and associations , 1983, Transactions of the Royal Society of Edinburgh: Earth Sciences.

[8]  A. Peccerillo,et al.  PetroGraph: A new software to visualize, model, and present geochemical data in igneous petrology , 2005 .

[9]  A. Hofmann,et al.  Precambrian crustal components, plutonic associations, plate environment of the Hercynian Fold Belt of central Europe: Indications from a Nd and Sr isotopic study , 1988 .

[10]  J. Leterrier,et al.  A classification of volcanic and plutonic rocks using R1R2-diagram and major-element analyses — Its relationships with current nomenclature , 1980 .

[11]  E. Jelínek,et al.  Modelling Diverse Processes in the Petrogenesis of a Composite Batholith: the Central Bohemian Pluton, Central European Hercynides , 2000 .

[12]  C. Braithwaite,et al.  Low-pressure Granulites of the Lisov Massif, Southern Bohemia: Visean Metamorphism of Late Devonian Plutonic Arc Rocks , 2006 .

[13]  C. Pin,et al.  Deciphering the petrogenesis of deeply buried granites: whole-rock geochemical constraints on the origin of largely undepleted felsic granulites from the Moldanubian Zone of the Bohemian Massif , 2004, Earth and Environmental Science Transactions of the Royal Society of Edinburgh.

[14]  Ross Ihaka,et al.  Gentleman R: R: A language for data analysis and graphics , 1996 .

[15]  S. Taylor,et al.  The continental crust: Its composition and evolution , 1985 .