EARTH SURFACE PROCESSES, VOL. 5,101-102 (1980)

BOOK REVIEWS

WORLD SOILS. E. M. Bridges, 2nd edn. Cambridge University Press, 1978. Price E7.95 (Hardback); f3.95 (Paperback).

are accompanied by representative horizon descriptions and standard nomenclature.

A chapter on soil mapping follows the climatic group- ings of soils and emphasizes the topographic template

Once again it is a pleasure to review this introductory text on soil science. This second edition incorporates substantial revision and additions-there are an addi- tional 31 pages of t ex twh i l e remaining true to its original aim of presenting soils in a style and language capable of reaching a wide audience.

The first part of the book devotes itself to the under- standing of soil as a natural entity, beginning with the soil profile and working through physical and chemical composition to the factors of soil formation and proces- ses which determine differences between soil profiles. There then follows a chapter on soil classification, expanded to incorporate the contrasting systems now in use, including the U S . Comprehensive System and the various European systems. The latter is a skilfully concise treatment. The following chapters deal with soils in various climatic zones as well as those which fall outside a zonal treatment. Those unfamiliar with this book will wish to know that the book carries 32 excellent colour illustrations of soils and that the many soil types

evident at the local-scale. This chapter acts as a l ink between the soils earlier described and a final chapter which discusses the extent, evaluation and use of soil resources.

Though the aim of this final chapter was clear enough I do feel that it is more of a rag bag than it need have been. Its actual title is clumsy while the last chapter seems hardly an appropriate place to start talking about soil fertility and soil nutrients which should clearly have been included in Chapter 2. In this respect Chapter 2 is seen to be inadequate as it stands as regards soil ‘chem- ical’ composition.

These criticisms aside, I feel Mike Bridges has made good use of the extra elbow room offered by the revision and it should be said that there was, and still is, the need for a text of this kind.

RICHARD T. SMITH School of Geography

University of Leeds

THERMOPHILIC MICROORGANISMS AND LIFE AT HIGH TEMPERATURES. T. D. Brock, Springer-Verlag, 1978. No. of pages: 465.

This book reports on research conducted between 1965 and 1975 on the environments and microbiology of a number of hot springs in Yellowstone National Park. Much of the information presented has been previously reported in over 100 papers. by the author and his co-workers. However, this text provides a useful summary of the work carried out in the Yellowstone area. The major part of this book (8 of the 14 chapters) is

taken up in a description of the various genera of micro-organisms to be found in the Yellowstone hot springs. A further three chapters contain detailed descriptions of specific environments. It is evident from this emphasis that the book is primarily aimed at the biologist or microbial ecologist. This is not to say that the book is of no geological or geomorphological interest since, in Chapter 11, the author suggests a model explaining the formation of Precambrian stromatolites based upon contemporary processes observed in the

Yellowstone area involving thermophilic micro- organisms.

Stromatolites, which are defined by Brock as follows: ‘Megascopic organo-sedimentary structures produced by sediment trapping, binding, and/or precipitation as a result of growth and metabolic activity of organisms, primarily blue-green algae’ provide a micro-fossil record of the Precambrian. Brock describes investiga- tions in Yellowstone into the microbiology and morphogenesis of stromatolitic mats within the hot springs. The mats were formed in springs of pH 7 to 9 with temperatures of up to 70°C. Within the mats the predominant organisms were the filamentous pho- tosynthetic bacterium, Chlorofzexus and the blue-green alga Synechococcus. The morphology and microbiology of stromatolitic columns is also described by Brock. These columns occur in waters of 32°C to 59°C with pH values of 7 to 9. The predominant organisms found in the columns were Fhormedium truncatum oar. thermale and Phormedium terve oar. grariuliferum, although the previously mentioned Chlorofzexits and Synechococcus organisms were also present. Brock explains the shape of stromatolitic columns in terms of Phormedium

@ 1980 by John Wiley & Sons, Ltd.

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metabolism and he hypothesises that similar morpho- genic processes might have been operative during the formation of Precambrian Conophytons.

A further implication of the work, reported by Brock, is that stroinatolitic mat formations do not necessarily indicate the presence of blue-green algae since mats of Chloroflexus alone can be obtained in conditions of low light intensity or high sulphide concentration. This is a significant observation because previous workers have assumed stromatolite rocks to be indicative of blue- green algae and therefore the build-up of atmospheric oxygen. If these rocks were actually produced by pho- tosynthetic bacteria, such as Chloroflexus, which are anoxygenic, then, as Brock points out, caution is required in dating the start of atmospheric oxygen evolution from biological evidence alone.

In Chapter 14 Brock gives an amusing insight into how the ten year investigation into the Yellowstone thermal springs was commenced and why he finally decided to seek new areas of research interest. The book is well produced and includes many photographic prints of the field study areas as well as microscopic studies of the various organisms. There are few typographical errors, however, one notable exception occurs on page 337 where Precambrian sedimentary rocks are dated at 3 million, not 3 billion, years old.

DAVID KAY School of Geography

University of Leeds

SCANNING ELECTRON MICROSCOPY IN THE STUDY OF SEDIMENTS, W. Brain Whalley (Ed.), Geo Abs- tracts, Norwich, England, 1978. No. of Pages: 414. Price: f12.75.

With its advantages of extraordinary depth of focus, great and continuous range in magnification, and now simultaneous X-ray compositional analysis, the scan- ning electron microscope (SEM) is an indispensible instrument in many fields of science and technology. In the earth sciences, it is being applied with great effect to the study of many groups of microfossils, used for environmental diagnosis from the surface textures of sand grains, and employed in the analysis of sandstone and limestone diagenesis, to name but three major areas of application. New uses for the instrument continue to be found and its potential seems unbounded.

This book arises out of a Symposium on ‘Scanning Electron Microscopy in the Study of Sediments’ held at the University College of Swansea in September 1977 under the auspices of the British Geomorphological Research Group and the British Sedimentological Research Group. It is the first of its kind in the field of sedimentology.

The book, beginning with a short Preface by its Edi- tor, Dr. W. B. Whalley, comprises a total of 29 articles which can be attributed wholly or in part to eight fields. As might have been predicted, most of the papers (13) are concerned with the surface textures of sedimentary particles and their environmental significance. A thoughtful review and examination of future prospects in this area is given by Dr. D. H. Krinsley. Seven papers relate to the diagenesis of sediments, a reflection of the growing value of scanning electron microscopy in this field. Dr. B. Waugh, a leading student of diagenesis by means of the SEM, contributes a valuable review of

red-bed diagenesis. The fabrics of sediments rich in clay-minerals form the subject of four papers, and there are two contributions on the pores of incompletely cemented rocks. There is one paper on cathodolumin- scence in scanning electron microscopy, another on the combined use of the SEM and the high voltage electron microscope, and an intriguing paper by N. K. Tovey in which the SEM is used to examine the continuous deformation of a single sand grain held in a miniature shear box. Scott and Collinson contribute an unusual and interesting paper on plant-related sedimentary particles, including fusain, under the SEM.

The papers which form this volume, as is inevitable, are diverse in scope, intention, and quality. While some are concerned almost wholly with technique, and others are pot-boilers or thin and rather mediocre when related to the generality in their particular field, most are of good quality and a few are very helpful, being either thoughtful reviews or reports of full-bodied investiga- tions. The book is in paperback, and the text, printed from camera-ready typescript, appears on coated paper, so that the all-important photographic illustrations are generally very good in quality. The editor of a symposium volume cannot be too scrupulous, but one could have wished in this case for fewer typographical errors and for the improvement of the more bizarre syntactic and structural forms submitted by certain of the authors. The book is nonetheless a useful addition to the field of scanning electron microscopy in sedimen- tology and deserves to be widely read, both for what has been achieved and as a stimulus for the future.

J. R. L. ALLEN Sedimentology Research Laboratory

University of Reading