Thermochronological methods: From paleotemperature constraints to landscape evolution models, edited by F. Lisker, B. Ventura and U. A. Glasmacher. Geological Society Special Publication 324, London, 2009. No. of pages: viii + 347. ISBN 978-1-86239-285-4
THERMOCHRONOLOGICAL METHODS: FROM PALEOTEMPERATURE CONSTRAINTS TO LANDSCAPE EVOLUTION MODELS, edited by F. Lisker, B. Ventura and U. A. Glasmacher. Geological Society Special Publication 324, London,2009. No. of pages: viii + 347. Price: £100.00. ISBN 978-1-86239-285-4 (hardback).
Geoffrey E. Batt*, * School of Earth and Environment, University of Western Australia (M006), 35 Stirling Highway, Crawley WA 6009, Australia.
As with many publications in this series, this substantial volume arose from a selection of papers presented at a major international meeting, in this case the European Conference on Thermochronology held in Bremen in 2006. The volume is not intended as a review of the full breadth and history of the field of thermochronology, although an abbreviated historical review of the subject (albeit biased towards the fission track field) is provided by the editors in their Preface and affords a good introduction. The aim of this collection is rather to capture the cutting edge of technical development and application in thermochronology. This is a challenging and commendable aspiration in a fast-moving field, particularly with 3 years between the conference that inspired it and the ultimate publication of the volume. However, although unquestionably containing a number of significant papers that should make it a useful addition to the library of most thermochronological labs, the volume is only partially successful in capturing the state of the art. The restricted geographical origin of the contributions alone, with only five of the 21 research papers originating outside Europe (and, notably, none from the productive and respected thermochronological labs of North America) must raise a question as to whether the ambition of summarizing recent developments in this area has been realized.
The 21 research papers are divided into two sections. The first seven papers present a range of innovative approaches to the acquisition and interpretation of thermochronometric data, while the second brings together a variety of case studies intended to demonstrate the utility of thermochronology as a tool in constraining dynamic geological settings. The technical papers are aimed squarely at practicing thermochronologists—in that most require significant background knowledge to understand the nature and implications of the work presented. The paper by Dobson et al. on refinements to analytical procedures for the zircon (U-Th)/He dating method, for example, requires in-depth familiarity with existing standard practice in the field to understand its significance. Similarly, the paper by Murrell et al. on fission track etching techniques for apatite, while significant, is clearly directed purely to the practicing fission track chronologist in providing a much-needed intercalibration of different variations on the chemical process that represents a key component of this method.
Papers by Gleadow et al. and Carter and Foster in this section are of particular note. Gleadow et al. present a much anticipated description of the coincidence mapping process at the heart of their innovative automated fission track analysis system. Although this approach is probably familiar to anybody following developments in the fission track method, thanks to a number of recent conference presentations on the subject, this represents the first formal publication putting the method and its results out for peer review and assessment, and hence deserves careful appraisal. At the heart of the automated track counting system is the concept of removing operator input from routine fission-track identification and counting. This is at once seductive for the promise of increased productivity and consistency, and troubling to some in a field where operator judgement has long been a critical (and hard-won) control on data quality. In light of this element of controversy, the obvious test required is a head-to-head comparison, automated recognition and counting system versus human operator. Surprizingly, only one such comparison is presented—comparing the automated system with an experienced operator (Andy Gleadow himself). The results show an excellent 1:1 correlation, but a more informative and persuasive outcome might have been derived from comparing the automated system with a range of operators and experience levels to better demonstrate the advantage of the consistency offered by new method.
Carter and Foster's contribution presents a novel approach exploiting the synergy of multiple analytical techniques—apatite fission track analysis and Nd isotopic measurements—to improve the precision of studies using apatite fission tracks to assess the dynamic geological implications of detrital sedimentary records. The addition of Nd isotope analysis allows differing apatite fission track grain ages to be associated with specific rock unit sources, thus removing a source of significant ambiguity from the interpretation of detrital data.
Although individually interesting, the papers in section two do not make an easy group. They could perhaps better have been divided into two: those dealing with case studies as natural examples of thermochronological behaviour on geological timescales (Kohn et al. and Kuhleman et al.); and those presenting case studies applying well-proven and understood thermochronometric techniques primarily to understand elements of the history of a particular region.
Overall, this volume is a significant contribution that contains some important and thought-provoking papers, but falls short of the ambitious intentions of the editors to capture the zeitgeist of the field of thermochronology.