The interpretation of geophysical data in exploration geophysics, well logging, engineering, mining and environmental geophysics requires knowledge of the physical properties of the rocks and their correlation. Physical properties are a "key" for combined interpretation techniques. The study of rock physics provides an interdisciplinary treatment of physical properties, whether related to geophysical, geotechnical, hydrological or geological methodology.The book is a comprehensive and concise systematic presentation of the physical properties of rocks. It is focussed on the problems of applied geophysics with respect to exploration and the expanding field of applications in engineering and mining geophysics, geotechnics, hydrology and environmental problems, and the properties under the conditions of the upper earth crust. This volume contains theoretical and experimental results relating to the main geophysical properties - density, magnetic properties, natural radioactivity, elastic and anelastic properties, electrical and thermal. It also presents the correlation between the individual properties as a basis of modern interpretation methods, including relationships between geophysical and geotechnical properties.