Geochemical Modelling of Igneous Processes – Principles And Recipes in R Language

The aim of this book is to unlock the power of the freeware R language to advanced university students and researchers dealing with whole-rock geochemistry of (meta-) igneous rocks. The first part covers data input/output, calculation of commonly used indexes and plotting in R. The core of the book then focusses on the presentation and practical implementations of modelling techniques used for fingerprinting processes such as partial melting, fractional crystallization, binary mixing or AFC using major-, trace-element and radiogenic isotope data. The reader will be given a firm theoretical basis for forward/reverse modelling, followed by exercises dealing with typical problems likely to be encountered in real life, and their solutions using R. The concluding sections demonstrate, using practical examples, how a researcher can proceed in developing a realistic model simulating natural systems. The appendices outline the fundamentals of the R language and provide a quick introduction to the open-source R-package GCDkit for interpretation of whole-rock geochemical data from igneous and metamorphic rocks.

Table of Contents

Chapter 1 Introduction

Part I R/GCDkit at Work
Chapter 2 Data Manipulation and Simple Calculations
Chapter 3 Classical Plots
Chapter 4 Specialized Plots
Chapter 5 Radiogenic Isotopes

Part II Modelling Major Elements
Chapter 6 Direct Models
Chapter 7 Reverse Models
Chapter 8 Forward Modelling in R
Chapter 9 Reverse Modelling in R

Part III Modelling Trace Elements
Chapter 10 Dilute Trace Elements: Partition Coefficients
Chapter 11 Direct (Dilute) Trace-Element Models
Chapter 12 Reverse (Dilute) Trace-Element Models
Chapter 13 Trace Elements as Essential Structural Constituents of Accessory Minerals: the Solubility Concept
Chapter 14 Forward Modelling in R
Chapter 15 Reverse Modelling in R

Part IV Radiogenic Isotopes
Chapter 16 Direct Models
Chapter 17 Reverse Models
Chapter 18 Forward Modelling in R
Chapter 19 Reverse Modelling in R

Part V Practical Modelling
Chapter 20 Choosing an Appropriate Model
Chapter 21 Semi-Quantitative Geochemical Approach
Chapter 22 Constraining a Model
Chapter 23 Numerical Tips and Tricks
Chapter 24 Common Sense in Action

Part VI Worked Examples
Chapter 25 Differentiation of a Calc-Alkaline Series: Example of the Atacazo-Ninahuilca volcanoes, Ecuador1
Chapter 26 Progressive Melting of a Metasedimentary Sequence: the Saint-Malo Migmatitic Complex, France1

Appendix A R Syntax in a Nutshell
Appendix B Introduction to GCDkit
Appendix C Solving Systems of Linear Algebraic Equations in R