Phanerozoic Earth History of Australia

Phanerozoic Earth History of Australia

64 Africa and Morocco (which makes the cover of the book), the Silurian-Devonian graptolites-bearing sections of Algeria and Morocco. Do not look for ...

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64 Africa and Morocco (which makes the cover of the book), the Silurian-Devonian graptolites-bearing sections of Algeria and Morocco. Do not look for structural description of the concerned areas, not for attempts of continental palaeo-reconstructions involving these areas. But if you plan to undertake such kind of work, or are, in some way, concerned with Lower Palaeozoic rocks and Africa, you actually need this book. It is a pity that this fourth volume in the series "Lower Palaeozoic Rocks of the World" will be the last one. Andr6 Michard, Strasbourg

J.J. Veevers (Editor), 1984. Phanerozoic Earth History of Australia. Clarendon Press, Oxford, xv + 418 pp., £55.00 (hardcover). "The Australian continent represents a fortieth of the earth's surface, and a sixteenth of the continental lithosphere. Its land area is the same as that of the conterminous United States of America, but its margins are wider." So begins the preface to this new book on the geology of Australia. Given that it covers such a vast area, it is remarkable how little impact the geology of Australia has had on geological thinking, compared for example, with the United States, or with the relatively tiny area of the British Isles. If pressed, the average geologist from north America or Europe would find it hard to say much about the geology of the continent, except that most of the western part of the continent has been a stable craton since the pre-Cambrian. A few notable curiosities may come to mind, such as the famous opal localities, or the remarkable late pre-Cambrian Ediacara fauna, but not much else. The reasons for Australia's geological obscurity are not hard to identify. The small population of the continent is concentrated in only a few coastal cities; the center is almost uninhabited; distances are great and field conditions hard. Much effort has been spent on geological mapping in recent years, and now Australian geological re-

search is the equal of any in the world. Geologists around the world who are concerned with large scale problems would welcome a review of the geology of Australia with open arms. A book entitled Phanerozoic Earth History of Australia then, ought to be both timely and desirable. Unfortunately, this book, one of the Oxford ~3eological Science Series, will satisfy very few readers. Like many books written by teams or committees, it suffers badly from a lack of clear structuring, and much of its value is lost in a vast welter of local detail and terminology. Few of the fourteen contributors seem to have been able to stand far enough back from their subject material to set it in a broader context. Nowhere is the old adage about seeing the wood for the trees more applicable. To be sure, some readers may need a lot of detail in compiling their own studies of individual problems, but it is exceptionally difficult for the more general reader to obtain a clear view of what happened in Australia over the last 600 million years. One way to have satisfied both requirements would have been to have included some review or synoptic chapters in addition to the detailed material. A vague attempt has been made in this direction, in the form of a final section (there are no 'chapters') entitled "Synopsis". This synopsis, however, includes barely three pages of text. Most of it is taken up by a series of diagrams, rather pompously entitled "Cinematograph", which illustrate the large scale evolution of the continent. These diagrams are a good idea, and very useful, but they are no substitute for a good review. There are six major sections to the book. After a rather perfunctory introduction, there is a section on Australia's global setting, which traces the separation of the continent from Antarctica and its later plate tectonic progress, and goes on to describe the paleoclimatic and biogeographic history. The plate tectonic section includes an excellent set of map reconstructions showing the position of the continent and evolving spreading ridges at intervals of a few million years. Even the

65 most amateur geologist is aware that Australia's fauna is unique, and not just because of the marsupials. One might hope, therefore, to find in the biogeographic section a clear and interesting account of the evolution of the Australian fauna and flora. Sadly, the section turns out to be a turgid, almost unreadable summary, in which the author has attempted to compress too much detail into too small a space. The author also seems to assume that the reader is already familiar with what is being discussed, but needs to know the detailed references to every fact or argument. It may be significant that the 25page biogeographic section has its own bibliography of over 300 references, whereas all the references to other sections are combined at the back of the book. Doubtless some readers will find this exhaustive bibliography valuable. The third section deals with lithospheric structure, and describes the geophysical structure of the continent. It is one of the most interesting parts of the book, because it accounts for so much of the geology of both the past and present. Unfortunately, it is rather b r i e f - - a bare ten pages. Much the most lenghtiest sections in the book are the fourth, which deals with the "morphotectonics" of the Australian platform and margins, and the fifth, which is purely historical. The choice of the term "morphotectonics" is indicative of the heavy handed approach used throughout the book. There is much more minor 'detail on the tectonics than the average reader is ever likely to want to know, and it is difficult to see the "big picture". The authors include a quotation from Wegener: " F r o m the southeast came the huge Australian block with its front thickened like an anvil: New Guinea (folded to form a high-altitude moun~

tain range) plus shelf; this forced itself between the chains of the southernmost Sunda Islands and the Bismarck Archipelago". They clearly admire Wegener's clarity of vision and pithy prose; it is a pity they do not share them. The eponymous section on Australia's Phanerozoic history constitutes the largest part of the book, some 130 pages. Phanerozoic time is described in three parts, the Potoroo (95-0 Ma); Innamincka (320-90 Ma) and the Uluru (575-320 Ma). These periods are termed "regimes", an expression reminiscent of political or governmental systems, but presumably intended to convey the sense of long periods of continuity. There is, of course, no explanation of what the authors actually intended. Most of the section is, as one would expect, an exhaustive study of Phanerozoic paleogeography and stratigraphy, backed up with a very comprehensive set of references. It is difficult for a reviewer without a minutely detailed knowledge of Australian stratigraphy to judge the soundness of the treatment. Overall, then, Phanerozoic Earth History of Australia is a very poor book, albeit one that must have taken considerable time and effort to put together. One wonders why the Oxford Series editors did not do a more careful internal review before publication. With some judicious pruning, and the inclusion of more synoptic and signposting material, a much better and more generally useful book could have emerged. As it is, the best that can be said for the present book is that it exists; a reference source that will be invaluable until it is eclipsed by something better. P. Francis, Houston, Texas

Geochemistry T.S. Bowers, K.J. Jackson and H.C. Helgeson, 1984. Equilibrium Activity Diagrams. Springer Verlag, Berlin, 397 pp., DM 98.00 (hardcover).

This book contains a compilation of 3648 activity diagrams depicting equilibrium phase relationships among minerals and an aqueous