Multi-Ring Basins

Multi-Ring Basins

276 horizontal density differences, pressure head between entrances and tidal rectification. Neither of the models systematically explores these diff...

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horizontal density differences, pressure head between entrances and tidal rectification. Neither of the models systematically explores these different driving mechanisms, let alone their interactions. The question whether or not the general circulation may be decoupled from the all pervasive tides in the region is a matter of debate, but not in this volume. Secondly, in discussing the vertical structure of the general circulation it will be evident that everything depends on at least two interrelated factors, the value of the vertical eddy viscosity and the absence or presence of density stratification. Any mentioning of the latter in the discussion of the dynamics of the seasonal (1) variation of the circulation pattern is absent. Apart from that, different modellers use vertical eddy viscosities that may differ by a factor of 10. No surprise then, that predictions about the vertical shear of the currents vary strongly between models and that models may show unrealistically large differences between surface and bottom currents in areas where these differences are known to be small, for instance the Southern Bight, owing to vigorous tidal mixing. Evidently the modellers have difficulty in simulating the right Ekman dynamics. It would now be easy to conclude that what this book lacks is what Dooley has done in one of the papers for a specific locality, to let the observations speak first and subsequently to analyze them from the physical oceanographical point of view rather than to take, in a rather arbitrary way, equations and boundary conditions for granted and to see what comes out if we change the external forcing a bit. However, it may well be that the volume reflects simply our ignorance about the dynamical problems at hand. In that case it is hightime for the physical oceanographers to take part in a discussion that now for too long has been dominated by numerical modellers, J.T.F. Zimmerman (Texel, The Netherlands)

Proceedings of the Twelfth Lunar and Planetary Science Conference. Pergamon Press, 1982, Vol. I, 1018 pp., Vol. II, 1823 pp., US $175.00, £110.00

ISBN 0-08-028074-9.

‘Multi-Ring Basins~ Proceedings of Lunar and

Planetary Science, Pergamon Press, 1981, Volume 12, Part A, 288 pp., US $35.00, £22.00, ISBN 0-08-028045-5. Basaltic Volcanism on

the

Terrestrial Planets.

Basaltic Volcanism Study Project, 1981. Pergamon Press, 1286 pp., US $60.00, £38.00, ISBN 0-08028086-2. ‘Impact and Explosion Cratering~ Proceedings of

the Symposium on Planetary Cratering Mechanics. Pergamon Press, 1977, 1299 pp., US $150.00, £98.00, ISBN 0-08-022050-9. These books, all beautifully printed with exemplarily clear diagrams and illustrations and many spectacular photographs, are a superb contribution to the planetary science literature. The Proceedings of the Twelfth Houston Lunar and Planetary Science Conference— this, as all the other Proceedings except the second, published by Pergamon Press—covers a wide field Mars, Venus, the Galilean satellites, meteorites as well as the Moon. Yet remarkably, so long after the last Apollo landing, studies of the lunar rocks and interpretations make up one of the two volumes. One or two papers given at the meeting were evidently judged too heterodox (or too daring!) to appear in this worthy collection which, as it were, leaves no stone unturned (e.g., depositional history of core). In the last decade there have been orders of magnitude improvement in techniques: minute amounts of material can now be analysed by an ever increasing range of techniques. Terrestrial geology is now reaping some of the benefit. It is perhaps invidious to select papers for comment among so many important contributions, but the following I found very interesting: O.B. James’ careful study of the Apollo 16 rocks enables her to date the Nectaris impact as 3.9 Ga. L.L. Hood’s remarkable feat in modelling the very small magnetic anomalies mapped by the Apollo 15 and 16 sub-satellites. Russell, Coleman & Goldstein’s attempt to determine the existence of a lunar iron core. In the second volume there is an excellent set of colourcoded maps of Mars; geology, topography and gravity. Many papers on meteorites reflect the —

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influence of techniques developed for Moon rocks. The idea that certain achondrites are igneous rocks from Mars is discussed. The study of the palaeomagnetism of meteorites is advanced by important papers by Nagata and by Strangway. The basaltic volcanism on the terrestrial planets and the books on impact craters nicely complement each other: together they show how both internal processes and meteorite impacts have fashioned the surfaces of the terrestrial planets and now a similar task is being done for the icy satellites of the major planets. The volcanism volume is a vast work by large numbers of distinguished participants; the most thorough effort in comparative planetology yet made: for the Earth is fully treated a remarkable achievement in reducing the vast amount of information to a reasonable length. Impact and explosion cratering is again a collective and authoritative work on natural and artificial terrestrial craters and on the impact craters on the Moon and terrestrial planets. Much effort has gone into attempts to understand the mechanics of cratering but the last section on scaling reveals how much more has to be done. The discovery that the lunar maria were multiring impact basins and the initial attempts to explain them is a very fascinating chapter of planetary science and it is well told by W.K. Hartmann. G.W. Wetherill and R.B. Baldwin recognize the importance of the basins as throwing light on the smaller bodies which must have been very numerous in the early solar system. The last great impact basins are now well mapped but unravelling the exact processes of formation is difficult and a number of interesting papers consider the physical processes involved. Planetary and geoscientists alike are greatly indebted to the editors and to Pergamon Press for these magnificent contributions to their science. —

S.K. RUNCORN (Newcastle upon Tyne, Gt. Britain)

Developments in Volcanology Volumes 1, 2 and 3. Forecasting Volcanic Events. H. Tazieff and J.C. Sabroux (Editors). 1983, 636 pp., US $78.75, Dfl

185.00, ISBN 0-444-42241-2. Arc Volcanism. S. Aramiki and I. Kushiro (Editors). 1983, 634 pp., US $97.75, Dfl 230.00, ISBN 0-444-42234-X. Explosive Volcanism. M.F. Sheridan and F. Barberi (Editors). 1983, 482 pp., US $84.75, Dfl 220.00, ISBN 0-444-42251-X. The publication of a new series of books on volcanology by Elsevier raises two interesting and quite separate questions of ethics in science. One issue concerns possible conflicts that can arise because there are both academic and commerical objectives in the publication of scientific literature. The other question is raised in volume 1 of this series and relates to scientific philosophy in forecasting and studying volcanic eruptions. Ethics become a central question, since the opinions of volcanologists have important sociological, economic and political consequences. I feel obliged to comment on both these issues, as well as inform the reader of the content, quality and value of the books. Two of these volumes (2 and 3) are reprinted directly out of the Journal of Volcanology and Geothermal Research. Volume 2, entitled Arc Volcanism, contains selected papers from an international symposium on this topic held in Tokyo, Japan in 1981. Volume 3, entitled Explosive Volcanism, is a collection of papers which were originally presented at a Workshop in May, 1982 in Italy. A substantial number of the papers are about Italian volcanoes and demonstrate the improving status and high quality of Italian volcanology. Journal of Volcanology and Geothermal Research is a high quality publication and is now regarded as the premier vehicle for publishing volcanological research. Consequently, most of the papers in both volumes are of high standard and a few papers are outstanding. As is often the case in publication of the proceedings of scientific meetings, there are also a few mediocre papers, which would perhaps not get in under normal circumstances. Ethical questions arise, however, about the justification of reprinting volumes of a wellestablished journal and touting these reprints around as a book. Surely most libraries and institutions who have an interest in volcanology