- Email: [email protected]
Rock dynamics and geophysical exploration
242
Rock Dynamics and Geophysical Exploration. (Developments in Geotechnical Engineering, 8.) Leif N. Persen. Elseder, Amsterdam, 1975, ix + 276 pp., Dr1. 78.00. This book by Professor Leif Persen, a well-known research worker in the field of rock dynamics, is number eight in a series of important books falling under the general title of "Developments in Geomechanics". It is a scholarly work on a subject which is not usually given the treatment that it merits in books devoted to rock mechanics, on the grounds, presumably, that it is generally considered as being outside the core of geomechanics and geotechnics, certainly as these subjects are taught at university level. Equally, rock dynamics, in an engineering sense, is usually given inadequate space in geophysics textbooks. But in spite of these omissions, the subject of rock dynamics has been of considerable interest to many research workers for a number of years, and so the book is a timely one. The term "rock dynamics" has both theoretical and practical connotations, covering the field of wave transmission from natural (seismic) and man-made sources. In the latter respect, the sources may be from engineering or quarrying works concerned with excavation and prod~:ction or for the purposes of site ~vestigation (examination of the strength and competence of ground). Professor Persen's treatment is directed mainly towards the theoretical side of the subject which is developed from first principles through the first 7 of 14 chapters. Such an approach is inarguably correct in a book of this type, but the level of mathematical treatment to which the reader is exposed means that the benefits of the book will be denied to many potential readers who have not attended mathematical courses throughout a university undergraduate training. For those readers not impeded in this manner, the mathematical treatment and the style of its presentation are quite satisfactory. The later chapters describe experimental work designed to examine the theoretical pred~;ctions of the earlier chapters. It is not possible to leap directly into these chapters without acquiring the necessary backing know. ledge from the earlier chapters and especially an understanding, in the absence of a list at either front or back of the book, of the symbols used by the author. The final two chapters, one dealing with scaled distance laws and attenuation and the other with tunnel wall stability, will be of particular interest to civil and structural engineers. Although the words "geophysical exploration" appear in the title of the book, this should really be read as 'seismic exploration' since the many other methods of indirect geophysical ground investigation are not -- indeed cannot be -- covered in a rock dynamics book. A title such as "Theoretical rock dynamics" would have summarized more accurately the contents of the book for the intending purchaser. Having mentioned the lack of a symbol list, the reviewer also mildly complains that there are only seven references in the book and notes that it is somewhat expensive in terms of cost per page. However, as a quite sophisticated text in the field of rock dynamics for rock engineers, and to
243
some degree for geophysicists, the book has no close rivals of similar academic quality. Although some subjects are omitted that might have been considered, for example, in an extended treatment of shock waves, the book will undoubtedly sell to those people. There will be a demand for the book from university libraries, since final year undergraduate and postgraduate students in geophysics and research students in rock mechanics will want to refer to it during the course of their investigations. For the serious student in its field of study, the book is a welcome and timely addition. P.B. A T T E W E L L
(Durham)
Physical Aspects of Natural Catastrophes. A.E. Scheidegger. Elsevier, Amsterdam, 1975, xiv + 289 pp., DR. 70.00. Natural catastrophes used to be endowed with a kind of unholy fascination, and not just to the layman. I remember, while I was a graduate student of soil mechanics, how Karl yon Terzaghi regularly punctuated his lectures with anecdotes of disaster. He would reach his climax with a triumphant: "and z e n . . , ninety-six people vere hilled!!!", after which he limpingly strode from the podium, mantle aflow, tailed by two devoted assistants. Alas, mankind has supped full of horrors, and we can no longer muster a decent sense of awe before necrological statistics. Catastrophes have become commonplace and dull like yesterday's headlines. Though Adrian Scheidegger tells us twice that 4,000 people were killed Jn the Mt. Huascaran avalanche of 1962 and that "the accident was repeated" in 1970 with the loss of 70,000 lives, I think he is right in otherwise sparing us the numerical details of human tragedy. This is by rio means the only nice feature of the book, however. The emphasis is entirely on geophysics, even though the author recognizes the difficulty of separating the physical and social aspects of natural catastrophes. An effort is made to incorporate some notions of elementary probability, especially in the treatment of earthquakes and volcanic eruptions. I turned first to the chapter on slope stability, wt,Jch contains Professor Scheidegger's most recent personal contributions. I f.Jund it, for an unfamiliar subject, surprisingly easy going. The physical concepts ~xe unstartling; they boil down to solid friction and classical plasticity. There are tidbits of involuntary humor here and there, as in the section entitled "Rolling Stones". "Experience indicates that, once loose from a slope, rocks soon start rolling." Whether they gather any moss is left unsaid. The strong points of the book are its basically sound physics, its sensible approach to natural phenomena, and its useful and constructive orientation. Scheidegger gives information whenever he can: peak discharge of lightning. worldwide changes in sea level, the names of reservoirs which have triggered earthquakes, the power of a tornado, how to compute extreme floods, air speeds in thunderclouds, and the difference between an ash flow and an ash
Rock Dynamics and Geophysical Exploration. (Developments in Geotechnical Engineering, 8.) Leif N. Persen. Elseder, Amsterdam, 1975, ix + 276 pp., Dr1. 78.00. This book by Professor Leif Persen, a well-known research worker in the field of rock dynamics, is number eight in a series of important books falling under the general title of "Developments in Geomechanics". It is a scholarly work on a subject which is not usually given the treatment that it merits in books devoted to rock mechanics, on the grounds, presumably, that it is generally considered as being outside the core of geomechanics and geotechnics, certainly as these subjects are taught at university level. Equally, rock dynamics, in an engineering sense, is usually given inadequate space in geophysics textbooks. But in spite of these omissions, the subject of rock dynamics has been of considerable interest to many research workers for a number of years, and so the book is a timely one. The term "rock dynamics" has both theoretical and practical connotations, covering the field of wave transmission from natural (seismic) and man-made sources. In the latter respect, the sources may be from engineering or quarrying works concerned with excavation and prod~:ction or for the purposes of site ~vestigation (examination of the strength and competence of ground). Professor Persen's treatment is directed mainly towards the theoretical side of the subject which is developed from first principles through the first 7 of 14 chapters. Such an approach is inarguably correct in a book of this type, but the level of mathematical treatment to which the reader is exposed means that the benefits of the book will be denied to many potential readers who have not attended mathematical courses throughout a university undergraduate training. For those readers not impeded in this manner, the mathematical treatment and the style of its presentation are quite satisfactory. The later chapters describe experimental work designed to examine the theoretical pred~;ctions of the earlier chapters. It is not possible to leap directly into these chapters without acquiring the necessary backing know. ledge from the earlier chapters and especially an understanding, in the absence of a list at either front or back of the book, of the symbols used by the author. The final two chapters, one dealing with scaled distance laws and attenuation and the other with tunnel wall stability, will be of particular interest to civil and structural engineers. Although the words "geophysical exploration" appear in the title of the book, this should really be read as 'seismic exploration' since the many other methods of indirect geophysical ground investigation are not -- indeed cannot be -- covered in a rock dynamics book. A title such as "Theoretical rock dynamics" would have summarized more accurately the contents of the book for the intending purchaser. Having mentioned the lack of a symbol list, the reviewer also mildly complains that there are only seven references in the book and notes that it is somewhat expensive in terms of cost per page. However, as a quite sophisticated text in the field of rock dynamics for rock engineers, and to
243
some degree for geophysicists, the book has no close rivals of similar academic quality. Although some subjects are omitted that might have been considered, for example, in an extended treatment of shock waves, the book will undoubtedly sell to those people. There will be a demand for the book from university libraries, since final year undergraduate and postgraduate students in geophysics and research students in rock mechanics will want to refer to it during the course of their investigations. For the serious student in its field of study, the book is a welcome and timely addition. P.B. A T T E W E L L
(Durham)
Physical Aspects of Natural Catastrophes. A.E. Scheidegger. Elsevier, Amsterdam, 1975, xiv + 289 pp., DR. 70.00. Natural catastrophes used to be endowed with a kind of unholy fascination, and not just to the layman. I remember, while I was a graduate student of soil mechanics, how Karl yon Terzaghi regularly punctuated his lectures with anecdotes of disaster. He would reach his climax with a triumphant: "and z e n . . , ninety-six people vere hilled!!!", after which he limpingly strode from the podium, mantle aflow, tailed by two devoted assistants. Alas, mankind has supped full of horrors, and we can no longer muster a decent sense of awe before necrological statistics. Catastrophes have become commonplace and dull like yesterday's headlines. Though Adrian Scheidegger tells us twice that 4,000 people were killed Jn the Mt. Huascaran avalanche of 1962 and that "the accident was repeated" in 1970 with the loss of 70,000 lives, I think he is right in otherwise sparing us the numerical details of human tragedy. This is by rio means the only nice feature of the book, however. The emphasis is entirely on geophysics, even though the author recognizes the difficulty of separating the physical and social aspects of natural catastrophes. An effort is made to incorporate some notions of elementary probability, especially in the treatment of earthquakes and volcanic eruptions. I turned first to the chapter on slope stability, wt,Jch contains Professor Scheidegger's most recent personal contributions. I f.Jund it, for an unfamiliar subject, surprisingly easy going. The physical concepts ~xe unstartling; they boil down to solid friction and classical plasticity. There are tidbits of involuntary humor here and there, as in the section entitled "Rolling Stones". "Experience indicates that, once loose from a slope, rocks soon start rolling." Whether they gather any moss is left unsaid. The strong points of the book are its basically sound physics, its sensible approach to natural phenomena, and its useful and constructive orientation. Scheidegger gives information whenever he can: peak discharge of lightning. worldwide changes in sea level, the names of reservoirs which have triggered earthquakes, the power of a tornado, how to compute extreme floods, air speeds in thunderclouds, and the difference between an ash flow and an ash