This book is unique in bridging the gap between geology and geophysics. Its integrative approach presents students and researchers in these disciplines with other methodologies as they try to understand the Earth's processes. It runs the gamut of earth sciences, from earthquakes and seismic exploration to thermal convection and the orogenic processes. Each chapter starts with the well-established facts and then proceeds through a logical framework to the most conjectural questions, such as continental drift in Paleozoicc and Precambrian times or mantle convection. Many of the issues discussed here do not yet have unanimously agreed solutions, but the extensive references point the reader to further possibilities.