Author: Alan Boudreau
Publisher:  Cambridge University Press
Book Review by: Sonu Chandiram

I had never before come across the word ‘hydromagmatic’ but I figured it had something to do with water, with the root word ‘hydro’ in it. I was familiar with the word ‘magma’ which refers to molten material within or beneath the earth’s crust.

Searching on Amazon’s website for books with this word, I found just three items on it: this book that I am reviewing, a second one by Kenneth Wohletz published in 1982 with no book cover and just the title Scanning Electron Microscopy of Basaltic Hydromagmatic Ash, and an Amazon music album entitled  Hydromagmatic Fragmentation.

So I figured Alan Boudreau is some sort of geologic pioneer who has researched on a new class of rocks and published his findings in this one-of-a kind book.  And that’s exactly what this book is, a pioneering introduction to a new type of rock where water plays an important part.

So what new stuff will you, the established or aspiring geologist, find in this book? A lot, I must say. Instead of going through the book item by item, let me provide you an overview of the book’s contents by simply listing the titles of its chapters:

  1. Introduction
  2. Layered Intrusions: an Overview
  3. Magmatic Volatiles and Fluids
  4. Geochemistry of the Platinum-Group Elements
  5. Generation and Movement of Bubbles and Volatile Fluids in a Crystal-Liquid Mush
  6. Halogens in Layered Intrusions
  7. Melt and Fluid Inclusion
  8. Pegmatoids, Pipes and Potholes
  9. The Effects of Volatiles on Mineral Stability and Volatile Fluxing
  10. Chromatographic Effects
  11. Compaction-Driven Stratigraphic Traps and the Formation of Great Dyke-Type Deposits
  12. Chromatites
  13. Isotopic Evidence
  14. Some Objections Covered

Within each of the above-listed chapters, you will find loads of information you probably have not encountered before, so feast yourself with these new goodies.

Pioneers typically are inquisitive and constantly searching for answers that arise in their heads. This is also the case with this book’s author Alan Boudreau. While you now have an inkling of what you will find in this book just from glancing at the chapter titles listed above, what else do you think will be the topics of future exploration?

They are the following, discussed in chapter 14 of this book within the section entitled Future Work. You might expect the topics to be discussed in the next edition of this book:

  • Fluid Inclusion Studies
  • Experimental Work
  • Numerical Modeling Studies
  • Detailed Petrographic and Isotopic Studies

A true eye opener, this book is certainly worth getting, especially if you have that pioneering, entrepreneurial spirit of discovery, and a ‘can-do’ and ‘will-do’ attitude.



Alan Boudreau is a Professor of Geology at Duke University with its main campus in Durham, North Carolina. He is an expert on the origins of layered intrusions. He has worked on numerical modeling of crystallization processes such as crystal aging and compaction, and how they  give rise to the variety of features observed in these intrusions.

He is also interested in the role of igneous fluids in the petrogenesis of platinum-group element (PGE) deposits in layered intrusions, including the understanding of the interaction of igneous fluids with liquid-crystal assemblages to produce the observed features.