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Geotectonics
92
thermal energy is the resource that exists in undiscovered h y d r o t h e r m a l convection systems. The first section of the b o o k on principles closes w i t h an article on the environmental aspects of geothermal development. Problems and avenues of solution f o r water quality degradation, corrosive emissions, induced seismicity, and land subsidence are discussed. However, a limiting environmental consideration of 'geothermal water rights' similar to that occurring in the development of underground irrigation water is not discussed; this well may be a severe constraint on utilization of low and medium temperature hydrothermal resources, as evidenced by recent court cases and statutes arising f r o m utilization of the system in Klamath Falls, Oregon. Pages 2 2 1 - 3 3 5 in the b o o k are devoted to case histories of e x p l o r a t i o n , development and utilization of a low-temperature resource in the Pannonian Basin, Hungary and high-temperature resources in Japan, Iceland, New Mexico (U.S.), and El Salvador. The Pannonian Basin article reveals the full e x t e n t of utilization possible for a low enthalpy resource, and should be looked at closely, both because of the ease of integration of the resource into the society and because of the p r o b a b i l i t y of finding such low temperature resources. The case history of Takinoue, Japan is interesting because of unique geology and the fact that the area lies w i t h i n a National Park. The d i f f i c u l t problem of h o t dry rock e x p l o r a t i o n is described in the case history of the Jemez Mountains--Valles Caldera area in New Mexico, U.S. The h y d r o t h e r m a l resource of the area is also described. The b o o k could have benefited from better editing in some of the articles, but it is an excellent addition to the geothermal literature. Illustrations and reference lists in general are excellent; and workers in the field of geothermics should find it to be of interest and u t i l i t y . It appears to do a commendable job of d o c u m e n t i n g the state of geothermal understanding at the beginning of the 1980's. William D. Stanley, Denver, Colo.
TECTONICS W. Beloussov, 1981. Geotectonics. SpringerVerlag, Berlin, and M i r Publishers, Moscow, 330 pp., DM 48.00. This is a translation of a 1976 revised Russian edition by Mir Publishers. The main subjects are oscillatory movements, ancient end modern; block injection and crumpling folding; intracrustal faults, endogenous continental regimes; platform and orogenic regimes, rifts and magmatic activization; the sediments, rocks and structures of the ocean floor; geophysical data on the earth's shape, rotation and structure; a historical review of geotectonic ideas, a critique of the 'new global tectonics'; and a search for a synthesis including the conditions for the development and interrelation of continental endogenous regimes. Geotectonics is defined as 'a geological discipline studying movements of the earth's crust to considerable depths, and also the structures formed by such movements.' Well, if y o u want to read about t h e evolution of the oceans by megasubsidence, about gravitational processes which are said to be the main controlling factors behind all geological structures, and about a diatribe against plate tectonics, then this b o o k is for y o u . In a way this b o o k is a review of the personal ideas of one man, and rather sadly ideas that have changed little over several decades. With m y own prejudice, which I admit, I find it d i f f i c u l t to understand h o w anyone can ignore all the develo p m e n t s of the last t w e n t y years and so still hold on w i t h a sort of tunnel-vision, to preplate tectonic ideas. For example, 'the new global tectonics c o m p l e t e l y ignores tectonic events taking place outside geosynclines in ancient and y o u n g platforms' - - w h a t about rifts, aulacogens and slipline indentation faults? An 'it is hard to understand h o w the oceanic lithosphere which is very poor in potassium could differentiate on melting into the material of the grantic-gneissic layer, so rich in p o t a s s i u m ' . - - I suggest a course in trace element geochemistry related to the p r o d u c t i o n of melts and their fract i o n a t i o n above subduction zones, followed by partial melting of lower crust to form K granites. I suppose to counteract any pre-
93 judice one has to ask questions like 'can tens of thousands of geologists convinced of plate tectonics have been hoodwinked for so long?' and 'are there many young geologists finding evidence which corroborates the views of Beloussov?' A negative answer on both accounts is predictable. In the interests of free debate it is important to acknowledge counterposing ideas, but I would only recommend this book to those interested in the history of science. Brain F. Windley, Leicester
G.
Boillot,
tinental
1981.
Geology of the Con.
Margins
translated by A l w y n Acarth). Longman Group Ltd., Harlow, Essex, xi + 115 pp., £stg. 4.95. 'This book is an introduction to the geology of the continental margins, where regional descriptions are avoided in favour of the analysis of geodynamic phenomena and the description of explanatory models', as noticed by the author. Therefore, the t e x t b o o k is a compendium of knowledge about the structural and geodynamic model of the continental margins in the frame of the new plate tectonics theory stated before 1978, the French edition being dated from 1979. A coherent sequence of six chapters, well organised and well balanced, provides a self-sufficient elementary course. Each chapter (about t w e n t y pages is preceded by a brief abstract or list of topics covered. Chapter I provides a survey of the morphology of the oceans and the continents and a summary of the theory of plate tectonics. In chapter 2 the various geodynamic factors causing crustal subsidence are reviewed and their effects are compared. Chapter3 deals with the structural and sedimentary evolution of stable margins created by the divergence of t w o plates or resulting from their strike-slip motion. Chapter4 describes the main morphological and structural features developing between t w o convergent plates including the seismic and gravimetric effects of subduction and the deep structure of the active island arcs and margins.
Chapter 5 is devoted to the thermal and petrological features associated with subduction including the generation of magma at depth. In the last chapter, the author studies the effects of collision between continents and/or island arcs and the formation of fold mountains. In conclusion the modern geodynamic concept is confronted with the old geosynclinal model. The text is very concise and elucidated by numerous (85) figures extracted from classical publications. Several bibliographic references for 'further reading' are given at the end of each chapter. The English translation is very faithful and the bibliography has been updated by the author for the English edition. Because the aim of this book and its introductory character, omissions are noticed. So, kinematics of relative movements of plates is not discussed. Several argumentations of the author may be open to criticism by specialists. For instance, the author writes (p. 84): 'the most frequent (earthquake) foci are situated within the descending plate . . . . and the creation of primary magmas ought to occur very close to the surface of the descending plate. Thus the magma source areas and the true Wadati--Benioff zone are probably separated by a certain distance.' A t present, because of accuracy in determining earthquakes, foci are located in a very thin layer which is the upper edging of the downgoing slab where the magma source areas are situated. Nevertheless this book provides a synthesis and a broad presentation of present ideas on the evolution of continental margins. The present volume is hardly addressed to students of geology, geophysics, petroleum engineering but all those interested in earth science will benefit from this book. Claude Blot, Sollies-Pont Peter F. Ballance and Harold G. Reading (Editors). 1980. Sedimentation in ObliqueSlip Mobile Zones. Special Publication No. 4 of the International Association of Sedimentologists. Blackwell Scientific Publications, Oxford, G.B., v i + 2 6 5 p p . , £stg. 14.50.
thermal energy is the resource that exists in undiscovered h y d r o t h e r m a l convection systems. The first section of the b o o k on principles closes w i t h an article on the environmental aspects of geothermal development. Problems and avenues of solution f o r water quality degradation, corrosive emissions, induced seismicity, and land subsidence are discussed. However, a limiting environmental consideration of 'geothermal water rights' similar to that occurring in the development of underground irrigation water is not discussed; this well may be a severe constraint on utilization of low and medium temperature hydrothermal resources, as evidenced by recent court cases and statutes arising f r o m utilization of the system in Klamath Falls, Oregon. Pages 2 2 1 - 3 3 5 in the b o o k are devoted to case histories of e x p l o r a t i o n , development and utilization of a low-temperature resource in the Pannonian Basin, Hungary and high-temperature resources in Japan, Iceland, New Mexico (U.S.), and El Salvador. The Pannonian Basin article reveals the full e x t e n t of utilization possible for a low enthalpy resource, and should be looked at closely, both because of the ease of integration of the resource into the society and because of the p r o b a b i l i t y of finding such low temperature resources. The case history of Takinoue, Japan is interesting because of unique geology and the fact that the area lies w i t h i n a National Park. The d i f f i c u l t problem of h o t dry rock e x p l o r a t i o n is described in the case history of the Jemez Mountains--Valles Caldera area in New Mexico, U.S. The h y d r o t h e r m a l resource of the area is also described. The b o o k could have benefited from better editing in some of the articles, but it is an excellent addition to the geothermal literature. Illustrations and reference lists in general are excellent; and workers in the field of geothermics should find it to be of interest and u t i l i t y . It appears to do a commendable job of d o c u m e n t i n g the state of geothermal understanding at the beginning of the 1980's. William D. Stanley, Denver, Colo.
TECTONICS W. Beloussov, 1981. Geotectonics. SpringerVerlag, Berlin, and M i r Publishers, Moscow, 330 pp., DM 48.00. This is a translation of a 1976 revised Russian edition by Mir Publishers. The main subjects are oscillatory movements, ancient end modern; block injection and crumpling folding; intracrustal faults, endogenous continental regimes; platform and orogenic regimes, rifts and magmatic activization; the sediments, rocks and structures of the ocean floor; geophysical data on the earth's shape, rotation and structure; a historical review of geotectonic ideas, a critique of the 'new global tectonics'; and a search for a synthesis including the conditions for the development and interrelation of continental endogenous regimes. Geotectonics is defined as 'a geological discipline studying movements of the earth's crust to considerable depths, and also the structures formed by such movements.' Well, if y o u want to read about t h e evolution of the oceans by megasubsidence, about gravitational processes which are said to be the main controlling factors behind all geological structures, and about a diatribe against plate tectonics, then this b o o k is for y o u . In a way this b o o k is a review of the personal ideas of one man, and rather sadly ideas that have changed little over several decades. With m y own prejudice, which I admit, I find it d i f f i c u l t to understand h o w anyone can ignore all the develo p m e n t s of the last t w e n t y years and so still hold on w i t h a sort of tunnel-vision, to preplate tectonic ideas. For example, 'the new global tectonics c o m p l e t e l y ignores tectonic events taking place outside geosynclines in ancient and y o u n g platforms' - - w h a t about rifts, aulacogens and slipline indentation faults? An 'it is hard to understand h o w the oceanic lithosphere which is very poor in potassium could differentiate on melting into the material of the grantic-gneissic layer, so rich in p o t a s s i u m ' . - - I suggest a course in trace element geochemistry related to the p r o d u c t i o n of melts and their fract i o n a t i o n above subduction zones, followed by partial melting of lower crust to form K granites. I suppose to counteract any pre-
93 judice one has to ask questions like 'can tens of thousands of geologists convinced of plate tectonics have been hoodwinked for so long?' and 'are there many young geologists finding evidence which corroborates the views of Beloussov?' A negative answer on both accounts is predictable. In the interests of free debate it is important to acknowledge counterposing ideas, but I would only recommend this book to those interested in the history of science. Brain F. Windley, Leicester
G.
Boillot,
tinental
1981.
Geology of the Con.
Margins
translated by A l w y n Acarth). Longman Group Ltd., Harlow, Essex, xi + 115 pp., £stg. 4.95. 'This book is an introduction to the geology of the continental margins, where regional descriptions are avoided in favour of the analysis of geodynamic phenomena and the description of explanatory models', as noticed by the author. Therefore, the t e x t b o o k is a compendium of knowledge about the structural and geodynamic model of the continental margins in the frame of the new plate tectonics theory stated before 1978, the French edition being dated from 1979. A coherent sequence of six chapters, well organised and well balanced, provides a self-sufficient elementary course. Each chapter (about t w e n t y pages is preceded by a brief abstract or list of topics covered. Chapter I provides a survey of the morphology of the oceans and the continents and a summary of the theory of plate tectonics. In chapter 2 the various geodynamic factors causing crustal subsidence are reviewed and their effects are compared. Chapter3 deals with the structural and sedimentary evolution of stable margins created by the divergence of t w o plates or resulting from their strike-slip motion. Chapter4 describes the main morphological and structural features developing between t w o convergent plates including the seismic and gravimetric effects of subduction and the deep structure of the active island arcs and margins.
Chapter 5 is devoted to the thermal and petrological features associated with subduction including the generation of magma at depth. In the last chapter, the author studies the effects of collision between continents and/or island arcs and the formation of fold mountains. In conclusion the modern geodynamic concept is confronted with the old geosynclinal model. The text is very concise and elucidated by numerous (85) figures extracted from classical publications. Several bibliographic references for 'further reading' are given at the end of each chapter. The English translation is very faithful and the bibliography has been updated by the author for the English edition. Because the aim of this book and its introductory character, omissions are noticed. So, kinematics of relative movements of plates is not discussed. Several argumentations of the author may be open to criticism by specialists. For instance, the author writes (p. 84): 'the most frequent (earthquake) foci are situated within the descending plate . . . . and the creation of primary magmas ought to occur very close to the surface of the descending plate. Thus the magma source areas and the true Wadati--Benioff zone are probably separated by a certain distance.' A t present, because of accuracy in determining earthquakes, foci are located in a very thin layer which is the upper edging of the downgoing slab where the magma source areas are situated. Nevertheless this book provides a synthesis and a broad presentation of present ideas on the evolution of continental margins. The present volume is hardly addressed to students of geology, geophysics, petroleum engineering but all those interested in earth science will benefit from this book. Claude Blot, Sollies-Pont Peter F. Ballance and Harold G. Reading (Editors). 1980. Sedimentation in ObliqueSlip Mobile Zones. Special Publication No. 4 of the International Association of Sedimentologists. Blackwell Scientific Publications, Oxford, G.B., v i + 2 6 5 p p . , £stg. 14.50.