Eos, Transactions American Geophysical Union

Principles of Geodynamics



Twenty years ago, when the second edition of Adrian Scheidegger's Principles of Geodynamics was published, the study of geodynamics, the internal processes of the earth, was a specialist subject. Within a decade, new and old concepts were pulled together in the unifying working hypothesis of plate tectonics, providing a global kinematic model of the upper layer of the earth. Much remains to be learned about geodynamics, but, during the last decade, in the framework of plate tectonics, it has become a valuable tool in our understanding of most dynamic geological processes. In the preface of the third edition, Scheidegger states that, ‘Although the headings of the chapters and sections are much the same as in previous editions, it will be found that most of the material is, in fact, new.’ This new look at the subject is timely, because although many basic concepts of geodynamics have not changed in the past 20 years, our approach to these concepts has been radically reoriented.