Understanding The Earth

During the past decade, research by oceanographic geophysicists which has led to the wide acceptance that continents drift about the face of the earth and to the concept of sea-floor spreading has culminated in an all-embracing theory known as 'plate tectonics.' This theory draws sea-floor spreading, continental drift, crustal structures, and world patterns of seismic and volcanic activity together as aspects of one coherent picture. Not only does it explain geophysical evidence and provide a framework within which geological data accumulated over the past two centuries can be fitted; it has also taken the Earth sciences to the stage where they can explain what has happened in the past and what is happening at the present time, and predict what will happen in the future. In addition, the book covers other currently exciting advances in the Earth sciences such as the accurate dating of rocks by radiometric methods; the Earth's internal composition, magnetic field, heat and internal temperatures; the Chandler Wobble; meteorites; and the Earth-Moon system. Three final chapters illustrate the role of the Earth sciences in society: earthquake prediction and modification, nuclear explosions and earthquakes, and a cautionary yet illuminating account of the Mohole project, which became "perhaps the greatest fiasco in the history of science." Although the book is arranged in a sequence the editors feel is a logical one for straightforward reading, each chapter is self-contained and is introduced by a brief explanatory preface.