- Economic Geology
Flow Processes in Faults and Shear Zones, Geological Society Special Publication 224. G.I. Alsop, R.E. Holdsworth, K.J.W. McCaffrey, and M. Hand, Editors. Pp. 392. Geological Society Publishing House, Unit 7, Brassmill Enterprise Centre, Brassmill Lane, Bath BA1 3JN, United Kingdom. 2004. Price£ 85.00
This book continues the long tradition of Geological Society special publications series, using the typical format of combining papers of thematic, specialist, and "case history" varieties. It contains 21 average-length papers and an introduction by Alsop and Holdsworth. The Transport and Flow Processes in Shear Zones meeting, on which the volume was based, was a joint effort by the Geological Societies of London, America, and Australia, held in September 2002. Much has been written in the past about shear zones, so I was curious to see what new or synoptic information would arise from this book, and also whether the book would be of interest to economic geologists and others who might not be specialist structural geologists. The introduction, by Alsop and Holdsworth, places the previous studies on shear zones into a broad lithospheric context based on frictional, frictional-viscous, and viscous regimes with increasing depth. Grain-scale processes, strain rates, network geometries, and fluid-rock microstructural processes are noted as the main modifiers of the general depth-dependency of shear zone behavior, and these topics set the scene for the remaining papers.
The first seven papers after the introduction deal with the changing process and products of shear zone deformation with depth and lithologic variation. Naturally enough, there is a diverse range of approaches by different authors. Although this diversity slightly clouds the attempts by the editors to group the papers into a logical sequence (i.e., a depth dependence to shear zone processes), I nonetheless thought the variety of approaches …