Physics and Chemistry of the Earth, Volume VI is a collection of research papers that present geochemical and geophysical investigations of the constitution and history of the earth; geological phenomena; and oil and ore formation. The book is composed of seven chapters written by different authors who are experts in the fields of geophysics and geochemistry. It covers the description of the structure and composition of the earth's mantle; a survey of the developments in the study of seismic surface waves; and model experiments of tectonic processes. Articles on the application of trace element data to problems in petrology and factors in the distribution of the trace elements during the crystallization of magmas, both important topics on mining, are presented as well. Geologists, geophysicists, geochemists, and students of petrology and mineralogy will find this book a good source of information.