Sedimentology

Sedimentology

ondary airflow over different types of bedforms, and sand transport on dunes. The chapter on the controls of dune morphology reads as a quest for an a...

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ondary airflow over different types of bedforms, and sand transport on dunes. The chapter on the controls of dune morphology reads as a quest for an answer, with, yes, it is the wind, but perhaps not for the reasons we think about today. The treatment on the development of sand seas is the rare case where a “geomorphic” text meets a “stratigraphic” text in blending surficial dynamics with accumulation of a stratigraphic record, and the recognition that this stratigraphic record is the chronology of aeolian system response to external forcing factors. Data abounds throughout the book to go beyond generalizations. Because of the “personal” approach, many examples are drawn from southern African and American case studies. The down side is a limited range in examples, but the greater up side is the continuity of building upon studies and areas that the author knows well. Because the book has such a topical treatment. reflecting where the field is today, it has a very contemporary feel. It is very readable besides. A contemporary text in a fast-moving field probably has a shorter shelf life than a more classical treatof ment, but at about $ 25 US, Geomorphology Desert Dunes was meant to be bought and digested, with the knowledge that a great many more things are yet to be discovered. G. Kocurek, Austin, TX PII

SOOl2-8252(96)00013-X

Sedimentology F. Ricci Lucchi, 1995. Sedimentographica: A Photographic Atlas of Sedimentary Structures, 2nd Ed. Columbia University Press, New York. Hardcover, X + 255 pp. Price: $47.00. ISBN O-231-10018-3. Until 1982 there were few books designed to help new students with the difficult business of learning how to deal with field outcrops of sedimentary rocks, how to observe, what to record and in what way such features might be interpreted. In particular there were very few texts that gave guidance on the interrelationships between the processes of origin and the

meso-scale sedimentary structures common in sedimentary rocks. This situation was addressed by the publication of Sedimentary Structures (Collinson and Thompson, 19821, an excellent text which showed students how observable outcrop-scale characteristics could be brought together with process-based interpretation and appropriate facies models. The forebears of the Collinson and Thompson text-book included: Pettijohn and Potter (1964), a largely photographic account of sedimentary structures; Reineck and Singh (19731, a well illustrated process account of depositional environments and Ricci Lucchi ( 1970), a magnificently photographic documentation of sedimentary structures. It is this latter work, the first edition, which forms the basis of this newly published second edition of Sedimentographica. The first edition was published in Italian, but this did not seem to matter as the beautiful pictures spoke for themselves. The stated aim of this photographic atlas is to illustrate the structures and other geometric aspects of sediments and sedimentary rocks. Like its predecessor it was originally published in Italian (1990) and only latterly in English. It quite rightly claims to show features with the “grace of sculpture, painting and tapestry”. It does not claim to be exhaustive as a catalogue of features. It is organised into eight chapters and an end section of colour plates. Photographs are present on all chapter pages, the chapters being essentially a collection of plates and their associated descriptions. Chapter 1 considers geometry of bedding and sedimentary bodies. Chapter 2 shows tractive structures produced by currents and waves. Chapter 3 illustrates traction and fall-out structures. Chapter 4 and 5 cover, respectively, transport and erosional features. Deformation structures are shown in Chapter 6, whereas biogenic, chemical and diagenetic structures are covered in Chapters 7 and 8. There is no question that this is an attractive book which has been produced with an artistic flair. It could grace any coffee table. The main question is whether it is useful in showing students the way to describe and interpret structures, and in the wider aspects of explaining processes and sequence development. It is here that I find great difficulties. Scientific usefulness has, to a great extent, been sacrificed

Book reviews

on the high alter of art. The text is rudimentary in places, explanations are simplistic and many of the photographs lack any form of scale. Some of the pictures are ambiguous or misleading. As an example, Plate 158 (p. 198) is labelled “Problematic traces: Chondrites”, but the Chondrires are not identitied in any way (i.e. no arrows etc.) and occur in association with other (more obvious) burrow types. Indeed, there is a general lack of arrows or identifiers on photographs. Thus, as a teaching document, this book could only be used with very close supervision and, to my mind, is of somewhat limited use.

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References Collision, J.D. and Thompson, D.B., 1982. Sedimentary Structures. Allen and Unwin, London. Pettijohn, F.J. and Potter, P.E., 1964. Atlas and Glossary of Sedimentary Structures. Springer, New York. Reineck, H.E. and Singh, LB., 1973. Depositional Sedimentary Environments. Springer, Berlin. Ricchi Lucci, F., 1970. Sedimentografia: Atlante Fotografico delle Strutture Primarie dei Sedimenti. 1st Ed. Zanichelli, Bologna.

B.W. Sellwood, Reading PI1 SOOl2-8252(96)00010-4