With the new global tectonics approach in the Earth Sciences, the quan titative aspects of the dynamics of rock-forming processes came into focus: geologists are no longer satisfied knowing the pressure-tempera ture conditions of the formation of a metamorphic rock or of the emplace ment of a magmatic body, but instead would like to learn the time history of these rocks as well, i. e. , derive the temperature-pressure-time path and relate it to a tectonic process. To achieve this goal, a knowledge of both pressure-temperature-dependent equilibria and the time scales at which these equilibria may be attained are essential. However, the latter kinetic information is much more difficult to retrieve than that on equilibria: whereas equilibria are controlled by state variables, and proper laboratory experiments may be directly applied to equilibrium natural assemblages, kinetics also depends on factors other than state variables, such as grain size, dislocation density, and especially time (rate of heating, duration of annealing, rate of cooling). Extrapolation of kinetic data obtained at high temperatures on laboratory time scales to more realistic lower tempera tures and geological time scales are dangerous because, for example, of possible changes from an intrinsically controlled defect regime to an extrinsic one as temperature is lowered, or from an interface-controlled to a diffusion-controlled reaction mechanism.

Volume 26 of Reviews in Mineralogy provides a multidisciplinary review of our current knowledge of contact metamorphism. As in any field of endeavor, we are provided with new questions, thereby dictating future directions of study. Hopefully, this volume will provide inspiration and direction for future research on contact metamorphism. The Mineralogical Society of America sponsored the short course on Contact Metamorphism, October 17-19, 1991, at the Pala Mesa Resort, Fallbrook, California, prior to its annual meeting with the Geological Society of America.

An introduction to the thin section description and interpretation of metamorphic rocks, their textures, and microstructures, for advanced undergraduate and graduate geology students. Sections cover some of the broader aspects of metamorphism and metamorphic rocks, the basics of description and interpretation of the textural/microstructural features from the simplest to the more complex, and advanced interpretations in polydeformed and polymetamorphosed rocks. Also available in paper (02414-2), $29.95. Annotation copyrighted by Book News, Inc., Portland, OR

A text which aims to help undergraduate students in geology to recognize and interpret metamorphic textures and microstructures in thin-section. For lecturers and postgraduates in geology and petrology, the book provides reference for the interpretation of metamorphic rocks.

This book presents the genetic connections of metamorphism and geodynamics. It discusses the tectonic and magmatic processes as the reason of metamorphism, and the geological types of metamorphism, which define the features of Р-Т parameters and Р-Т-t paths. Three categories of metamorphism are distinguished depending on the heat flow rate: 1) at a geothermal gradient near to an average terrestrial ("normal") value; 2) at a heightened thermal gradient as the result of additional heat supply in the earth's crust by magmatic intrusions and diapirism of magma; 3) at a reduced thermal gradient during the collision of lithosphere plates and blocks of the earth's crust. The quantitative methods of description of metamorphism have been widely used in this book. The mathematical models of metamorphism have been studied in connection with magmatic intrusions, rifting process and magmatic diapirism. Mineral changes in the rocks controlled by variations of Р-Т of parameters, mass transfer and chemical reactions have also been characterized. The book proposes a quasi-stationary model of diffusion metasomatism with respect to the formation of zonal structures of minerals. The method of mineral thermobarometry for the conditions of unsteady equilibrium has been worked out; the quantitative analysis of mass transfer during metamorphic reactions in the rock matrix has been carried out, and the mobility of chemical elements at metamorphism has been estimated as well. The book is intended for specialists in the fields of petrology, mineralogy and geochemistry, and for students at the senior and graduate level.

Microstructural Geochronology Geochronology techniques enable the study of geological evolution and environmental change over time. This volume integrates two aspects of geochronology: one based on classical methods of orientation and spatial patterns, and the other on ratios of radioactive isotopes and their decay products. The chapters illustrate how material science techniques are taking this field to the atomic scale, enabling us to image the chemical and structural record of mineral lattice growth and deformation, and sometimes the patterns of radioactive parent and daughter atoms themselves, to generate a microstructural geochronology from some of the most resilient materials in the solar system. First compilation of research focusing on the crystal structure, material properties, and chemical zoning of the geochronology mineral archive down to nanoscale Novel comparisons of mineral time archives from different rocky planets and asteroids and their shock metamorphic histories Fundamentals on how to reconstruct and date radiogenic isotope distributions using atom probe tomography Microstructural Geochronology will be a valuable resource for graduate students, academics, and researchers in the fields of petrology, geochronology, mineralogy, geochemistry, planetary geology, astrobiology, chemistry, and material science. It will also appeal to philosophers and historians of science from other disciplines.

This book represents the proceedings of the 9th written by a very active group of physicists at Kongsberg seminar, held at the Norwegian Mining the University of Oslo - physicists interested in Museum located in the city of Kongsberg about complex systems in general and geo-like systems 70 km Southwest of Oslo. The Kongsberg district in particular. is known for numerous Permian vein deposits of The content of the book is organized into three native silver, and mining activity in the area lasted major parts following the introductory chapter. for more than 300 years, finally ceasing in 1957. Chapters 2 to 7 primarily treat the role of fluids The previous eight Kongsberg seminars were in specific geological environments, ranging from focused on ore-forming processes and all of these sedimentary basins (Chapters 2-3) to contact were organized by Professor Arne Bj0rlykke, now metamorphic/hydrothermal scenarios (Chapters director of the Norwegian Geological Survey. 4-5) and regional metamorphic settings (Chapters Since process-orientated research tends to break 6-7). The following four chapters (8-11) focus down the traditional barriers between the different on various properties of fluid-rock systems that geological disciplines, this seminar has always are critical in controlling flow and transport been a meeting point for people with a variety through rocks. These include: mineral solubility of geological backgrounds.