This Dynamic Earth

Presents the online edition of the publication "This Dynamic Earth: The Story of Plate Tectonics" (ISBN 0-16-048220-8) by W. Jacquelyne Kious and Robert I. Tilling, published by the U.S. Geological Survey (USGS) in Denver, Colorado. Posts contact information via mailing address, telephone and fax numbers, and e-mail. Notes that a hard copy of the publication is available. Provides a table of contents and endnotes. Links to the USGS home page.

In the early 1960s, the emergence of the theory of plate tectonics started a revolution in the earth sciences. Since then, scientists have verified and refined this theory, and now have a much better understanding of how our planet has been shaped by plate-tectonic processes. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. Indeed, the notion that the entire Earth's surface is continually shifting has profoundly changed the way we view our world.

New technologies has given us many different ways to examine the Earth. For example, we can penetrate deep into the interior of our planet and effectively X-ray its internal structure. With this technology comes an increased awareness of how our planet is continually changing and a fresh awareness of how fragile it is. Designed for the introductory Physical Geology course found in Geology, Earth Science, Geography, or Physical Science departments, Dynamic Earth: An Introduction to Physical Geology clearly presents Earth's dynamic geologic systems with their many interdependent and interconnected components. It provides comprehensive coverage of the two major energy systems of Earth: the plate tectonic system and the hydrologic cycle. The text fulfills the needs of professors by offering current content and a striking illustration package, while exposing students to the global view of Earth and teaching them to view the world as geologists.

Dynamic Earth presents the principles of convection in the earth's mantle in an accessible style. Mantle convection is the process underlying plate tectonics, volcanic hotspots and, hence, most geological processes. The book summarises key observations and presents the relevant physics starting from basic principles. The main concepts and arguments are presented with minimal mathematics, although more mathematical versions of important aspects are included for those who desire them. The book also surveys geochemical constraints and mantle evolution. The audience for Geoff Davies' book will be the broad range of geologists who desire a better understanding of the earth's internal dynamics, as well as graduate students and researchers working on the many aspects of mantle dynamics and its implications for geological processes. It is also suitable as a text or supplementary text for upper undergraduate and postgraduate courses in geophysics, geochemistry, and tectonics.

At last, an undergraduate textbook integrating the geophysics, geochemistry, and petrology of the Earth to explain plate tectonics and geodynamics.

This book is an attempt to put into practice these precepts of Popper and Koestler as far as they can be applied to the Earth sciences at an elementary level. It is felt that the time is ripe for such a presentation, for the revolution that has taken place over the past 20 years within the Earth sciences has made more people directly aware of the way science works and of the necessity of knowing its history to achieve a full understanding of the problems involved. Emerging from the revolution has been the immensely unifying and extremely fruitful concept of plate tectonics, and developments leading to its establishment form the core of the book (Chs 4, 5 & 6). However, to see plate tectonics in context, it is necessary to look at what happened before, and this is done in the first three chapters. Chapter 1 is concerned with the development of ideas about the shape, size and mass of the Earth, which led to broad concepts about the Earth's structure and finally to a model of a cooling, contracting Earth, capable of explaining geological history and the major topographic features of the Earth. Chapter 2 goes on to show how even though the acceptance of this idea gradually broke down in the first half of the 20th century, possible alternatives, which are now at the core of plate tectonics, were also rejected.