Erosion And Sedimentation (the University Series In Geology)

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THE UNIVERSITY SERIES IN GEOLOGY Edited by RHODES W.FAIRBRIDGE Professor of Geology, Columbia University Termier, Henri and Genevieve Sehwarzbach, Martin Additional titles will Erosion and Sedimentation Climates of the Past be listed and announced as published. Henri Termier Professor of Geology, University of Paris (Sorbonne) Genevieve Termier Mattre de Recherches at the Centre Nationale des Recherches Scienlifiques, Paris Erosion and Sedimentation Translated by D. W. Humphries Department of Geology , University of Sheffield , England Evelyn E. Humphries D. VAN NOSTRAND COMPANY, LTD. LONDON PRINCETON, NEW JERSEY NEW YORK TORONTO D. VAN NOSTRAND COMPANY, LTD. 358 Kensington High Street, London, W.14 D. VAN NOSTRAND COMPANY, INC. 120 Alexander Street, Princeton, New Jersey 24 West 40 Street, New York 18, New York VAN NOSTRAND COMPANY (Canada) LTD. 25 Hollinger Road, Toronto 16 D. Copyright HENRI and 1963 GENEVI^VE TERMIER Printed and bound in England by Hazell Watson & Viney Ltd, Aylesbury and Slough Preface Geology today demands the knowledge of a large number of fundamental ideas which are provided by neighboring sciences. The student, or the geologist at the beginning of his career, runs the risk of losing himself in a multitude of details and complications, which will seldom be useful to him. To guide him, we have endeavored to prepare a work which is easy to read, not overburdened with tables and graphs, and which avoids swamping the reader with all the details of many specialized disciplines. Our aim is to stress the general facts and to bring out the conclusions which will enable the reader to reconstruct the great events that have taken place in the past on the surface of the earth. This volume frequently uses results obtained by geomorphologists and biologists, but it will not overlap with the treatises and manuals written by them, since its point of view is quite different. In attaining this objective, morphology is but one of the many ways which can serve to trace the history of our globe. The very important problem of uniformitarianism arises here. Like most geologists at the present day, we believe that the history of the surface of the earth can be explained almost entirely on the basis of observation of present-day phenomena. It is important, however, to note some limitations. Even among the processes which occur today, there are some which it is observe (for example, turbidity currents). Furthermore, very many mechanical, physical and chemical phenomena resulting from internal geodynamic processes, such as folds, metamorphism, and granitization, are difficult to only known by their effects. time factor: most of the events which modify the surface of the earth have a duration which greatly exceeds that of a human life. The conditions which have existed on the earth have changed considerably since the beginning of what we may call "Fossiliferous Times", that is to say, the last 600 million years. In fact, Organic Evolution cannot be doubted by anyone, and there must have been periods when the continents were entirely without a plant cover. Life, which seems to have appeared in the sea near to coasts, may have reached the ocean depths at about the same time as the surface of the continents emerged. We can also deduce the existence of a Geochemical Evolution, which It is necessary, also, to consider the develops in a way parallel to the evo