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Organic Metamorphism and Geothermal History Paul Robert D. Reidel Publishing Co., 1987, ISBN: 902 772 5004. Price: US$99.00, UK £64.95 This book is a comprehensive synthesis on the various aspects of the effects of temperature on the organic matter and some inorganic compounds during their geological history. The author has explored almost all aspects of the organic matter metamorphism including theory, methods of measurements, applicability to solve geological problems. Geologists from academic institutions will find there a good support for their students. Coal and petroleum geologists, together with geochemists will have the possibility to find a convenient background for interpreting organic matter metamorphism measurements that may be often a critical factor for coal and petroleum exploration. A number of geologic case studies are extensively analysed, with highlights on the usefulness of integrating geology and OM metamorphism studies.

The book is divided in four parts. The first deals with the thermal diagenesis of OM and the method of paleogeother- mal analysis. Although the historical chapter is somewhat longer than it could have been, this part gives all the required fundamentals on the measurements, the thermal degradation and the heat transfer. These fundamentals are clearly accessi- ble to any geologist, without any specific background in these topics, though some insights on the present research trends of this geologic science would have been of interest. Various examples are given, from Europe, West Africa and North America, where data and interpretation are clearly sepa- rated.

The second part is an outstanding synthesis on the study of organic matter in reflected light and fluorescence. Analytical procedure are detailed, together with an objective approach of the classification problems. The coalification process is described in detail and its relation to oil generation pointed out.

The third part is a set of geological case studies where the author took a very objective approach. The studied basins belong to various sets of geodynamic environment, but the author avoided imposing a given geodynamic model to ex- plain the geothermal history and the observed thermal altera- tion. Moreover, facts, hypotheses and conclusions are clearly illustrated.

The last part compares mineral and organic diagenesis. Though some causes of diagenesis may occur in both cases, the author clearly points out the difference of thermal evolution and the difficulty in ensuring satisfactory correla- tions between mineral and organic diagenesis.

This book is an objective reference for all geologists who want to find first hand information on the background of a number of data or correlations that are sometimes taken for granted.

P. Y. Chenet /nst/tut Frangais du Petro/e, France

Desert Sedim ts: Ancient and Modern L. E. Frostick and I. Reid (Eds) Geological Society Special Publication No, 35; 1987; ISBN: 0632-019050; 401 p. Price: £55.00

This book is the outcome of a two-day meeting of the same title held in London in May 1986. Twenty four of the papers presented are included in the book. The defining adjectives in the title do not indicate equal treatment of the ancient and modern. As is the case with so many conferences, the high aspirations of the organizers for a balanced programme is not always matched by the spread of papers offered. Only four papers are directly concerned with what one may term really ancient (Palaeozoic-Mesozoic) desert sediments, although several others take us well back into the Recent and Pleis- tocene. Age apart, it is nice to find a thematic group of papers that covers the whole spectrum of desert environments.

The book is divided into four main sections: Fluvial Sedi- ments, Aeolian sediments, Chemical Sediments and Remote Sensing of Desert Sediments. Fluvial Sediments is sub-divided into two parts. 'Process and form' contains two papers concerning the Negev of Israel (A. P. Schick et al., and S. Grossman and R. Gerson); the first involves the balance between coarse particles previously buried or exposed during floods. A third paper by Maizets describes several systems of Plio-Pleistocene river channels in Oman, now in inverted relief. Part two is on 'Tectonism, climatic change and fluvial desert sedimentation'. Here, Frostick and Reid describe tectonic controls on desert sediments, especially as studied by

them in the East African rifts. The sub-Recent is continued with papers by Harvey on the dissection of alluvial fans in Spain, and by M. A. J. Williams et al. on Quaternary landforms in the Tenere Desert of Niger, which includes an archaeological ly control led history of events back to >150 000 BP. The fourth paper of this group concerns the deposits of Lower Triassic ephemeral streams recognised in three Danish wells (H. Olsen).

Aeolian Sediments is divided into three sections. 'Dust dynamics and deposits' contains four papers. Whalley et al. show that, despite the experiments of Kuenen and Perdock over 20 years ago, dust resulting from aeolian abrasion probably has made important contributions to peri-desert accumulations of loess. Pye and Tsoar present a very useful summary of the mechanics and geological implications of dust transport and deposition in deserts, with special reference to the Negev, while Gerson and Amit discuss the rates and modes of dust deposition in the same area. Finally, Vine describes the possible incorporation of Saharan Pleistocene dust, transported by a palaeo-Harmattan, into the iron-rich soils of southern Nigeria.

'Dune dynamics and deposits' contains five papers. Gunati- laka and Mwango describe how changes in the level of the water table controls the relationship between sabkha pans

180 Marine and Petroleum Geology, 1989, Vol 6, May