For the first time, a book is available that bridges 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. The book covers 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 Paleozoic and Precambrian times or mantle convection. Many of the issues discussed here have not yet found unanimously agreed solutions, but the extensive references point the reader to further possibilities.