Deformation of Earth Materials by Shun Karato is a welcome addition to textbooks dealing with experimental rock mechanics and its application to natural rock deformation. It complements the recent second edition of Paterson & Wong's book (Experimental Rock Deformation: the Brittle Field), by dealing with ductile rock deformation mechanisms, and provides by far the most comprehensive and authoritative treatment of this field in recent years. It is squarely aimed at graduate students and researchers, although some advanced undergraduates will also find it a useful source. Karato is a leading expert in experimental rock deformation applied to mantle processes and the volume leans that way, to the extent that particular aspects of deformation in the continental crust are not covered, such as deformation–metamorphism relationships and flow of partially molten crustal rocks. On the other hand, much of the material is sufficiently general to be of interest to scientists working with either environment. Its value to students is enhanced through the incorporation of problem exercises at many points throughout the text and the volume is supported by a very comprehensive list of some 1500 original references.
The book provides a brief introduction to essential background material, such as stress, strain and elasticity, relevant thermodynamics (including defect chemistry, essential to appreciating the role of water in plastic flow of rocks), phenomenology of continuous deformation (including issues of stability and flow localization into shear zones).
The role of intracrystalline defects in plastic flow is summarized. The theories of flow by dislocation glide and dislocation creep are set out, plus creep by grain-size-sensitive processes such as diffusive mass transfer and grain boundary sliding. The influence of solid-state phase transformations on flow is reviewed along with the development of crystallographic preferred orientation during flow. All of these are supported and illustrated by reference to experimental data, mainly on ultrabasic rocks.
The final third of the book is devoted to aspects of the application of theoretical and laboratory mechanical studies to geodynamics. This section summarizes the composition of the Earth and how this impacts on the rheology of the interior, and how deformation of the surface and study of seismic velocities and attenuation help constrain those rheological properties. Internal heterogeneities of the Earth on a range of scales and their geodynamic implications, as exemplified by conclusions from relatively recent developments in seismic tomography and seismic anisotropy, are discussed in some detail.
Of course, a significant proportion of the material covered by this book can be found scattered about elsewhere. But its greatest value lies in the drawing together of traditional topics together with more recent developments such as the thermodynamic aspects of rock deformation and links with whole-Earth geodynamics. This is combined with a clear writing style and excellent illustrations to make this an essential addition to a researcher's bookshelf.
