Basalt is the most voluminous of all the igneous rocks. Extensive field, experimental, petrographic and geochemical studies of basalt have provided us with a considerable understanding of igneous petrogenesis, plate tectonics, and crust-mantle interaction and exchange. One important aspect of geology that has developed over the last few decades is the study of oceanic basalts. The ocean basins cover about two thirds of the earth's surface and are floored by a basement of oceanic basalt that is continuously undergoing generation at spreading centres and destruction at subduction zones, a process which throughout geological time is recognized as the principal means of generating new crust. The study of oceanic basalts enables us to understand better the generation and recycling of crustal materials (including the continental crust), and the exchange between oceanic crust and seawater via hydrothermal activity. Compositional variations displayed by oceanic basalts provide windows into the mantle, and the identification of isotopically-distinct mantle reservoirs demonstrates that the source of oceanic basalts is heterogeneous and is controlled by convection and reservoir interactions within the mantle.

appears to be mainly controlled by kinetic factors. Parageneses and compositions of phyllosilicates strongly depend upon available chemical components from precursor minerals or fluids. The alteration of other phases such as plagioclase and titanomagnetite provides components for formation of phyllosilicates. The degree of alteration in the basalts is mainly controlled by fluid/rock ratios, which in turn are determined by rock permeability.

The origin of different kinds of igneous rocks can be understood in terms of their tectonic setting, and by way of the isotope compositions of strontium, neodymium, and lead. This book explains the petrogenesis of igneous rocks as a consequence of tectonic processes resulting from interactions between asthenopheric plumes and the overlying lithospheric mantle. The relevant principles of isotope geochemistry are explained in the first chapter, making it accessible for university students as well as professionals. The relevant isotopic data is presented in diagrammatic form. The book contains more than 400 original drawings.

The field of Igneous Petrology has evolved greatly in the past years. McBirney's new Third Edition, completely revised and updated, presents a modern and integrated survey of the geological and genetic relations of igneous rocks. It illustrates how modern geochemical and geophysical methods can be combined with field relations to understand the generational and compositional evolution of magmas.

Vol. 174AX bound with Proceedings of the Ocean Drilling Program. Scientific results Vol. 174A.

Trace Elements in Igneous Petrology, 5: Developments in Petrology: A Volume in Memory of Paul W. Gast focuses on the contributions and influence of Gast in petrology, including crystallization, magmatic processes, isotopic composition, and ocean ridge basalt chemistry. The selection first takes a look at quantitative models of trace element behavior in magmatic processes; application of trace elements to the petrogenesis of igneous rocks of granitic composition; and an assessment of local and regional isotopic equilibrium in the mantle. Discussions focus on evidence derived from time constraints, scale of isotopic disequilibrium, fractional crystallization, trace element modeling, geodynamics and tectonic setting, partition coefficients, quantitative models for trace elements, and parameter determination and inverse-problem solution. The publication then examines the isotopic composition of lead in oceanic basalt and its implication to mantle evolution; strontium isotopes in basalts from the Pacific Ocean basin; and trace elements in ocean ridge basalts. Concerns cover variations in ocean ridge basalt chemistry, trace elements in ocean ridge basalts, disequilibrium partial melting, seawater alteration, background for lead isotope tracer studies, and uranium, thorium, and lead concentrations in basalts. The book examines trace elements and anorthosite genesis, lead isotopes in Archaean plutonic rocks, early Archaean rocks and geochemical evolution of the earth's crust, and factors controlling the noble gas abundance patterns of deep-sea basalts. The selection is a valuable source of data for researchers interested in petrology.