Custom diagrams for GCDkit

This is a collection of custom diagrams I wrote for GCDkit (Janoušek et al., 2006).

Installation

Copy the *.R files into the Diagrams/User/ subdirectory of your local GCDkit library.

You can check your local library path by running Sys.getenv("R_LIBS_USER") in an R session. If the R_LIBS_USER variable is unset you can run .libPaths() to get the full list of library paths R knows about.

Once copied, you will find the diagrams under the Plots > User defined menu item.

The diagrams are tested on Linux running R 4.1.0 and GCDkit 6.0.

Diagrams

• SiO₂–CaO/(CaO+K₂O) diagrams of Enrique & Esteve (2019).
  • Enrique, P. & Esteve, S. (2019). "A chemical approximation to the modal QAPF and normative Q' (F')-ANOR classification of the igneous rocks based on their SiO₂-CaO-K₂O content". Geogaceta, 66, 91–94. Link to PDF
  • Enrique, P. & Esteve, S. (2019). "Comparative study of the classification of plutonic and volcanic rocks using the normative Q' (F')-ANOR and chemical SiO₂–100⋅CaO/(CaO+K₂O) diagrams". Geogaceta, 66, 95–98. Link to PDF
• 2Q–(or+ab)–4an diagram of Enrique (2018).
  • Enrique, P. (2018). "Clasificación normativa de las rocas plutónicas saturadas y sobresaturadas en sílice basada en la clasificación modal QAP: El diagrama 2Q-(or+ab)-4an". Geogaceta, 63, 95–98. Link to PDF
• Al₂O₃ versus normative plagioclase diagram, figure 6 of Irvine & Baragar (1971).
  • Irvine, T. N. & Baragar, W. R. A. (1971). "A Guide to the Chemical Classification of the Common Volcanic Rocks". Canadian Journal of Earth Sciences, 8, 523–548. DOI 10.1139/e71-055
• Peralkaline quartz-normative extrusive rock classification of MacDonald (1974).
  • MacDonald, R. (1974). "Nomenclature and petrochemistry of the peralkaline oversaturated extrusive rocks". Bulletin Volcanologique, 38, 498–516. DOI 10.1007/BF02596896
• Basalt tetrahedron's Q-Ne-Ol plane, figure 2 of Yoder & Tilley (1962).
  • Yoder, H.S. & Tilley, C. E. (1962). "Origin of basalt magmas: An experimental study of natural and synthetic rock systems". Journal of Petrology, 3, 342–532. DOI 10.1093/petrology/3.3.342

Other references

Janoušek, V.; Farrow, C. M. & Erban, V. (2006). "Interpretation of Whole-rock Geochemical Data in Igneous Geochemistry: Introducing Geochemical Data Toolkit (GCDkit)". Journal of Petrology, Oxford University Press, 47, 1255–1259. DOI 10.1093/petrology/egl013

R Core Team (2024). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/

License

All the diagrams are released under the same license as GCDkit (i.e. GPL (>= 2)).