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Meteorite craters
186
A.N.U. has made an important contribution), the early history of the Earth, and oceanic and sediment evolution throughout geological time. But the volume taken as a whole succeeds well in conveying the “view of the Earth as seen from A.N.U.” and is one of the best available volumes of its kind. R.S. THORPE
(Milton
Keynes,
U.K.)
Meteorite Craters. G.J.H. McCall (Editor). Benchmark Papers in Geology, Vol. 36. Dowden, Hutchinson and Ross Inc., Stroudsburg, Pennsylvania. Distributed by John Wiley and Sons, Chichester, U.K., 1977, 364 pp., U.S. $44.50. Producing a book in this Benchmark series is no easy task. The job is carefully defined in the introduction, The author has to gather together, in about 360 pages the critical material needed to reconstruct the background of the subject. He has to lay the foundation bricks of the scientific edifice and provide a springboard for new studies. McCall’s discipline is the study of the geology of meteorite craters, proven and probable, on the surface of planet Earth. In this book he collects together 28 papers (4 from the 1930’s, 2 from the 1950’s, 16 from the 1960’s and 6 from the 1970’s) from journals as easily obtainable as “Nature” and “Science” to sources as far flung as the “Western Australian Museums Special Publications” and the “Proceedings of the Geological Association of Canada”. These papers are sifted into three classes, following the three classes of meteorite craters. Class I contains the proven meteorite craters, in which meteoritic material has been found at the site. Included here are firstly the explosion craters with diameters ranging from 100 m to several kilometers. The incoming body exploded when retarded in the ground producing radial elevation of the strata of bedrock relative to the centre of the crater. The crater usually contains impactites and rock flower, and does not contain meteoritic fragments, these being widely scattered all around, Secondly we have the impact craters which are usually smaller than 100 m. The incoming body has lost a lot of its cosmic velocity before impact and meteorite fragments are found in the crater. Class II craters show shock effects but no meteoritic material has been found. Class III craters have the character~tic physio~aphi~ form and structure of meteorite craters but show no shock effects or meteoritic fragments. McCall introduces each section with a few pages of comments and an extensive list of further references. I found that McCall’s words and the papers he selects made f~cinating reading. We are introduced to Earth craters with ray systems, Hooke’s attempts to reproduce “craters” in boiling alabaster, Seddon’s engrossing paper on crater formation hypotheses (a juggling act between eroded laco-
187
liths and impacting asteroids), and a complete range of geological surveys of individual craters (the papers bristling with such emotive names as Wolf Creek, Canyon Diablo, Bosumtwi, Tunguska, Henbury, Camp0 de1 Cielo, Merewether, Talemzana and so on). McCall makes it abundantly clear why (quoting Seddon) “geologists can study one medium sized hole in the ground for 70 years without feeling either that the last word has been said or that this is a cause for shame”. I enjoyed this book and am convinced that not only should every library have a copy but also anyone vaguely interested in the subject would benefit greatly by having his own copy continually close to hand. I have two minor criticisms. I would have liked some of the photo~aphic reproductions to be better but in the main this is not the editor or the publishers fault, they have simply reproduced the poor figures that appeared in the original papers. It is a pity though that better figures could not have been specifically produced for this volume. In the second criticism I think I am on more shakey ground, because I would have been happier if the “geology” had wandered more into the realms of “geophysics”. I think the book would have benefited from an extra hundred pages or so including papers on the physics of crater production, the occurrence rate of crater formation on the Earth and a brief introduction to intercomparisons between the craters on Earth and those on our planetary companions, Moon, Mercury and Mars, Maybe we can look forward to this in the second edition. DAVID W. HUGHES (Sheffield, U.K.)
The Structure of Turbulent Shear Flow. Second Edition, First paperback edition, 1980. Cambridge University 429 pp., L 7.95.
A.A. Townsend. Press, London,
This book is one of the best known monographs on turbulence. It was first published in 1956 and has become a standard reference for fluid dynamic&s and atmospheric scientists working in the field of shear flow turbulence. In 1976, an entirely rewritten and considerably expanded 2nd edition was published and, recently, a paperback version of this edition has become available. The approach of the book is that of the obse~ational scientist. Theoretical concepts are introduced as far as they are useful for the interpretation of observations. No attempt is made to cover modern theoretical developments towards a deduction of the properties of turbulent flows from the basic equations. Neither second order models nor direct numerical sim~ations of turbulent flows are mentioned in the book. Dimensional analysis, similarity principles, and scaling laws are the principal tools used by the author to interpret turbulent flows in pipes and channels, in jets and wakes, and in
A.N.U. has made an important contribution), the early history of the Earth, and oceanic and sediment evolution throughout geological time. But the volume taken as a whole succeeds well in conveying the “view of the Earth as seen from A.N.U.” and is one of the best available volumes of its kind. R.S. THORPE
(Milton
Keynes,
U.K.)
Meteorite Craters. G.J.H. McCall (Editor). Benchmark Papers in Geology, Vol. 36. Dowden, Hutchinson and Ross Inc., Stroudsburg, Pennsylvania. Distributed by John Wiley and Sons, Chichester, U.K., 1977, 364 pp., U.S. $44.50. Producing a book in this Benchmark series is no easy task. The job is carefully defined in the introduction, The author has to gather together, in about 360 pages the critical material needed to reconstruct the background of the subject. He has to lay the foundation bricks of the scientific edifice and provide a springboard for new studies. McCall’s discipline is the study of the geology of meteorite craters, proven and probable, on the surface of planet Earth. In this book he collects together 28 papers (4 from the 1930’s, 2 from the 1950’s, 16 from the 1960’s and 6 from the 1970’s) from journals as easily obtainable as “Nature” and “Science” to sources as far flung as the “Western Australian Museums Special Publications” and the “Proceedings of the Geological Association of Canada”. These papers are sifted into three classes, following the three classes of meteorite craters. Class I contains the proven meteorite craters, in which meteoritic material has been found at the site. Included here are firstly the explosion craters with diameters ranging from 100 m to several kilometers. The incoming body exploded when retarded in the ground producing radial elevation of the strata of bedrock relative to the centre of the crater. The crater usually contains impactites and rock flower, and does not contain meteoritic fragments, these being widely scattered all around, Secondly we have the impact craters which are usually smaller than 100 m. The incoming body has lost a lot of its cosmic velocity before impact and meteorite fragments are found in the crater. Class II craters show shock effects but no meteoritic material has been found. Class III craters have the character~tic physio~aphi~ form and structure of meteorite craters but show no shock effects or meteoritic fragments. McCall introduces each section with a few pages of comments and an extensive list of further references. I found that McCall’s words and the papers he selects made f~cinating reading. We are introduced to Earth craters with ray systems, Hooke’s attempts to reproduce “craters” in boiling alabaster, Seddon’s engrossing paper on crater formation hypotheses (a juggling act between eroded laco-
187
liths and impacting asteroids), and a complete range of geological surveys of individual craters (the papers bristling with such emotive names as Wolf Creek, Canyon Diablo, Bosumtwi, Tunguska, Henbury, Camp0 de1 Cielo, Merewether, Talemzana and so on). McCall makes it abundantly clear why (quoting Seddon) “geologists can study one medium sized hole in the ground for 70 years without feeling either that the last word has been said or that this is a cause for shame”. I enjoyed this book and am convinced that not only should every library have a copy but also anyone vaguely interested in the subject would benefit greatly by having his own copy continually close to hand. I have two minor criticisms. I would have liked some of the photo~aphic reproductions to be better but in the main this is not the editor or the publishers fault, they have simply reproduced the poor figures that appeared in the original papers. It is a pity though that better figures could not have been specifically produced for this volume. In the second criticism I think I am on more shakey ground, because I would have been happier if the “geology” had wandered more into the realms of “geophysics”. I think the book would have benefited from an extra hundred pages or so including papers on the physics of crater production, the occurrence rate of crater formation on the Earth and a brief introduction to intercomparisons between the craters on Earth and those on our planetary companions, Moon, Mercury and Mars, Maybe we can look forward to this in the second edition. DAVID W. HUGHES (Sheffield, U.K.)
The Structure of Turbulent Shear Flow. Second Edition, First paperback edition, 1980. Cambridge University 429 pp., L 7.95.
A.A. Townsend. Press, London,
This book is one of the best known monographs on turbulence. It was first published in 1956 and has become a standard reference for fluid dynamic&s and atmospheric scientists working in the field of shear flow turbulence. In 1976, an entirely rewritten and considerably expanded 2nd edition was published and, recently, a paperback version of this edition has become available. The approach of the book is that of the obse~ational scientist. Theoretical concepts are introduced as far as they are useful for the interpretation of observations. No attempt is made to cover modern theoretical developments towards a deduction of the properties of turbulent flows from the basic equations. Neither second order models nor direct numerical sim~ations of turbulent flows are mentioned in the book. Dimensional analysis, similarity principles, and scaling laws are the principal tools used by the author to interpret turbulent flows in pipes and channels, in jets and wakes, and in