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Alfred Wegener und die Drift der Kontinente
200
BOOK REVIEWS
with Kober and Stille in this century. The other school, with roots in the Greek Atomist tradition, maintains that orogeny is generally continuous, though locally episodic and irregular, and should be approached from a uniformitarian, non-deterministic standpoint; it is associated with such figures as Suess, Wegener and Argand. According to Seng/Sr this persistent controversy has its basis in metaphysical beliefs about uniformity and the orderliness of Nature and is not founded on observation. There is much to commend in the thought-provoking thesis he puts forward, but I disagree with his putting Peter Vail in the Stille school, when Suess, who he associates with the other school, first introduced the concept of eustasy. The key issue about global sea-level changes depends not on any underlying metaphysical belief but on hard evidence concerning stratigraphic correlation. A. Hallam, Birmingham
Continental Drift
Martin Schwarzbach, 1989. Alfred Wegener und die Drift der Kontinente. Wissenschaftliche Verlagsanstalt, Stuttgart. Softcover, 164 pp. Price: D.M.36,- ISBN 3-80471044-1. This booklet (164 pp.) a second and revised edition (1989) from Martin Schwarzbach, K61n, is devoted to the life and achievements of Alfred Wegener (18801930). It is intended to inform the historically interested reader about the background of Wegener, his career and the impact of his ideas to his contemporaries and to the present scientific community which has studied and finally confined plate tectonics 30 to 50 years after Wegeners death. The author makes it clear that the idea of moving continents was not totally new, but that Wegener was the first to summarize and formulate the hypothesis of continental drift based on a
wealth of observations from geology, paleontology and geophysics. The booklet starts with describing the background of Alfred Wegener's family, some great grandfather having been strongly influenced by the life and scientific achievements of Alexander von Humboldt. We read about Wegener's life as a student and his intentions as a young scientist in Berlin and Marburg, his efforts and first publication in astronomy and meteorology. His career as a balloon pilot with a new record in 1906 adds to characterize a colourful and adventurous part of Wegener's personality. After ample and heated discussions with K6ppen, his later father-in-law, he published his first articles about the origin of the continents (Die Entstehung der Kontinente) in 1912, publications that merged in a booklet in 1915, modified and revised several times in the 30's with latest additions (already including ideas about convection as a driving force) in 1929, one year before his tragic death in the ice of Greenland. There is a wealth of information about the development of Wegener's ideas between 1912 and 1930, the hostile reception of his first presentations and of his book which was translated into so many languages, the latest edition, again in English, published in 1966 and encouraged by the advent of plate tectonic concepts. Especially the geological community as explained by the a u t h o r - - a classical well known geologist himself--reacted sceptically. Most well-established and fixistic professors rejected Wegener's idea as "visions without background". Also a presentation of his work in the United States did not change the general front of established geoscience against him. There were exceptions: scientists who accepted the many facts Wegener had collected on both sides of the Atlantic, and although his ideas were slowly forgotten in the 40's and 50's a few scientists, the most prominent one being Du Toit from South Africa, found more and more evidence that the continents around the Atlantic must really have been stuck together in the Jurassic.
BOOKREVmWS The author describes many geological arguments for and against Wegener's hypothesis, the geophysical arguments being a bit underrepresented. I miss Jeffrey's arguments based on the growing knowledge of the small variations of the shear modulus with depth. At that time Jeffrey's arguments were hard to defeat and the weak asthenosphere had still to be detected. A nice chapter of the book summarizes Wegener's main ideas: (1) the isostatic concept, light continental Sial floating on (oceanic) Sima, like icebergs in water. (2) his assumed forces favoring pole fleeing (Polfluchtkraft) and tidal friction for pushing continents around. (3) the assumption of a huge crack in the middle between the outward drifting continents (although Wegener had inspected extensional cracks in Iceland he did not relate them to his theory). (4) mountain ranges created by compression on the leading edge of moving continents (!) (5) the concept of Pangea in the Paleozoic and Mesozoic with a visionary sketch of this huge land mass, quite similar to plate tectonic reconstructions 40 years later (!). An interesting comparison of these and other hypotheses to plate tectonics of the late 70's follows. This chapter is not totally on the latest state and the citations of some more sceptical observers seem a bit outdated. The booklet ends with a careful summary of the late glory of Alfred Wegener, lists of his most important scientific publications (out of about 500!), major books about his life and honors he received, most of them after his death. In general, the author has definitely succeeded to show the man Alfred Wegener with his many talents and his synoptic brain from a personal and human point of view, a man who stimulated evolutionary ideas in geology more than anybody else in the first half of our century.
R. Meissner, Kiel
201 A.W. Bally and A.R. Palmer (Editors), 1988.
The Geology of North America---An Overview, D N A G Project Volume A, The Geological Society of America. Two volumes, one hardbound of text with 619 pp. and the other a slipcase with 12 plates, indexed, 2 microfiche cards in pocket for references to several of the chapters. Price: U.S.$60.00. ISBN 08137-5207-8. This overview volume for the 27 other volumes of The Geology of North America (U.S., Canada, and Mexico) summarizes the major geologic features of North America and the adjacent oceanic regions and compliments the more detailed treatments presented in the other volumes. The editors, in the foreword, state: " W h e n the Decade of North American Geology Project got underway, it was planned that one of us would write this book as a summary of all the volumes of The Geology of North America. As the D N A G Project evolved, it became evident that delays in the final publication of some contributions would seriously compromise this ideal plan. Also, we wanted to have some kind of overview of the geology of North America available in time for the International Geological Congress to be held in Washington in the summer of 1989. We therefore modified our original plan and prepared this multi-author volume. Instead of a comprehensive and uniform synthesis, we now offer a series of papers that we hope cover many, if not most, key aspects of the regional geology of North America. Some of the authors of this volume are also authors a n d / o r editors of some of the other volumes of this series. We encouraged the authors to make their chapters a personal statement, which left them free to choose their own paths between encyclopedic completeness and their own idiosyncratic perspectives. Thus, John Wheeler, in reviewing a manuscript co-authored by one of us (AWB) pointed out that of the papers may represent more "a point of view" rather an "overview". Fortunately, it is precisely that
BOOK REVIEWS
with Kober and Stille in this century. The other school, with roots in the Greek Atomist tradition, maintains that orogeny is generally continuous, though locally episodic and irregular, and should be approached from a uniformitarian, non-deterministic standpoint; it is associated with such figures as Suess, Wegener and Argand. According to Seng/Sr this persistent controversy has its basis in metaphysical beliefs about uniformity and the orderliness of Nature and is not founded on observation. There is much to commend in the thought-provoking thesis he puts forward, but I disagree with his putting Peter Vail in the Stille school, when Suess, who he associates with the other school, first introduced the concept of eustasy. The key issue about global sea-level changes depends not on any underlying metaphysical belief but on hard evidence concerning stratigraphic correlation. A. Hallam, Birmingham
Continental Drift
Martin Schwarzbach, 1989. Alfred Wegener und die Drift der Kontinente. Wissenschaftliche Verlagsanstalt, Stuttgart. Softcover, 164 pp. Price: D.M.36,- ISBN 3-80471044-1. This booklet (164 pp.) a second and revised edition (1989) from Martin Schwarzbach, K61n, is devoted to the life and achievements of Alfred Wegener (18801930). It is intended to inform the historically interested reader about the background of Wegener, his career and the impact of his ideas to his contemporaries and to the present scientific community which has studied and finally confined plate tectonics 30 to 50 years after Wegeners death. The author makes it clear that the idea of moving continents was not totally new, but that Wegener was the first to summarize and formulate the hypothesis of continental drift based on a
wealth of observations from geology, paleontology and geophysics. The booklet starts with describing the background of Alfred Wegener's family, some great grandfather having been strongly influenced by the life and scientific achievements of Alexander von Humboldt. We read about Wegener's life as a student and his intentions as a young scientist in Berlin and Marburg, his efforts and first publication in astronomy and meteorology. His career as a balloon pilot with a new record in 1906 adds to characterize a colourful and adventurous part of Wegener's personality. After ample and heated discussions with K6ppen, his later father-in-law, he published his first articles about the origin of the continents (Die Entstehung der Kontinente) in 1912, publications that merged in a booklet in 1915, modified and revised several times in the 30's with latest additions (already including ideas about convection as a driving force) in 1929, one year before his tragic death in the ice of Greenland. There is a wealth of information about the development of Wegener's ideas between 1912 and 1930, the hostile reception of his first presentations and of his book which was translated into so many languages, the latest edition, again in English, published in 1966 and encouraged by the advent of plate tectonic concepts. Especially the geological community as explained by the a u t h o r - - a classical well known geologist himself--reacted sceptically. Most well-established and fixistic professors rejected Wegener's idea as "visions without background". Also a presentation of his work in the United States did not change the general front of established geoscience against him. There were exceptions: scientists who accepted the many facts Wegener had collected on both sides of the Atlantic, and although his ideas were slowly forgotten in the 40's and 50's a few scientists, the most prominent one being Du Toit from South Africa, found more and more evidence that the continents around the Atlantic must really have been stuck together in the Jurassic.
BOOKREVmWS The author describes many geological arguments for and against Wegener's hypothesis, the geophysical arguments being a bit underrepresented. I miss Jeffrey's arguments based on the growing knowledge of the small variations of the shear modulus with depth. At that time Jeffrey's arguments were hard to defeat and the weak asthenosphere had still to be detected. A nice chapter of the book summarizes Wegener's main ideas: (1) the isostatic concept, light continental Sial floating on (oceanic) Sima, like icebergs in water. (2) his assumed forces favoring pole fleeing (Polfluchtkraft) and tidal friction for pushing continents around. (3) the assumption of a huge crack in the middle between the outward drifting continents (although Wegener had inspected extensional cracks in Iceland he did not relate them to his theory). (4) mountain ranges created by compression on the leading edge of moving continents (!) (5) the concept of Pangea in the Paleozoic and Mesozoic with a visionary sketch of this huge land mass, quite similar to plate tectonic reconstructions 40 years later (!). An interesting comparison of these and other hypotheses to plate tectonics of the late 70's follows. This chapter is not totally on the latest state and the citations of some more sceptical observers seem a bit outdated. The booklet ends with a careful summary of the late glory of Alfred Wegener, lists of his most important scientific publications (out of about 500!), major books about his life and honors he received, most of them after his death. In general, the author has definitely succeeded to show the man Alfred Wegener with his many talents and his synoptic brain from a personal and human point of view, a man who stimulated evolutionary ideas in geology more than anybody else in the first half of our century.
R. Meissner, Kiel
201 A.W. Bally and A.R. Palmer (Editors), 1988.
The Geology of North America---An Overview, D N A G Project Volume A, The Geological Society of America. Two volumes, one hardbound of text with 619 pp. and the other a slipcase with 12 plates, indexed, 2 microfiche cards in pocket for references to several of the chapters. Price: U.S.$60.00. ISBN 08137-5207-8. This overview volume for the 27 other volumes of The Geology of North America (U.S., Canada, and Mexico) summarizes the major geologic features of North America and the adjacent oceanic regions and compliments the more detailed treatments presented in the other volumes. The editors, in the foreword, state: " W h e n the Decade of North American Geology Project got underway, it was planned that one of us would write this book as a summary of all the volumes of The Geology of North America. As the D N A G Project evolved, it became evident that delays in the final publication of some contributions would seriously compromise this ideal plan. Also, we wanted to have some kind of overview of the geology of North America available in time for the International Geological Congress to be held in Washington in the summer of 1989. We therefore modified our original plan and prepared this multi-author volume. Instead of a comprehensive and uniform synthesis, we now offer a series of papers that we hope cover many, if not most, key aspects of the regional geology of North America. Some of the authors of this volume are also authors a n d / o r editors of some of the other volumes of this series. We encouraged the authors to make their chapters a personal statement, which left them free to choose their own paths between encyclopedic completeness and their own idiosyncratic perspectives. Thus, John Wheeler, in reviewing a manuscript co-authored by one of us (AWB) pointed out that of the papers may represent more "a point of view" rather an "overview". Fortunately, it is precisely that