ALBERT

Description / Table of Contents: The review chapters in this volume were the basis for a short course on molecular modeling theory jointly sponsored by the Geochemical Society (GS) and the Mineralogical Society of America (MSA) May 18-20, 2001 in Roanoke, Virginia which was held prior to the 2001 Goldschmidt Conference in nearby Hot Springs, Virginia. Dr. William C. Luth has had a long and distinguished career in research, education and in the government. He was a leader in experimental petrology and in training graduate students at Stanford University. His efforts at Sandia National Laboratory and at the Department of Energy's headquarters resulted in the initiation and long-term support of many of the cutting edge research projects whose results form the foundations of these short courses. Bill's broad interest in understanding fundamental geochemical processes and their applications to national problems is a continuous thread through both his university and government career. He retired in 1996, but his efforts to foster excellent basic research, and to promote the development of advanced analytical capabilities gave a unique focus to the basic research portfolio in Geosciences at the Department of Energy. He has been, and continues to be, a friend and mentor to many of us. It is appropriate to celebrate his career in education and government service with this series of courses in cutting-edge geochemistry that have particular focus on Department of Energy-related science, at a time when he can still enjoy the recognition of his contributions. Molecular modeling methods have become important tools in many areas of geochemical and mineralogical research. Theoretical methods describing atomistic and molecular-based processes are now commonplace in the geosciences literature and have helped in the interpretation of numerous experimental, spectroscopic, and field observations. Dramatic increases in computer power-involving personal computers, workstations, and massively parallel supercomputers-have helped to increase our knowledge of the fundamental processes in geochemistry and mineralogy. All researchers can now have access to the basic computer hardware and molecular modeling codes needed to evaluate these processes. The purpose of this volume of Reviews in Mineralogy and Geochemistry is to provide the student and professional with a general introduction to molecular modeling methods and a review of various applications of the theory to problems in the geosciences. Molecular mechanics methods that are reviewed include energy minimization, lattice dynamics, Monte Carlo methods, and molecular dynamics. Important concepts of quantum mechanics and electronic structure calculations, including both molecular orbital and density functional theories, are also presented. Applications cover a broad range of mineralogy and geochemistry topics-from atmospheric reactions to fluid-rock interactions to properties of mantle and core phases. Emphasis is placed on the comparison of molecular simulations with experimental data and the synergy that can be generated by using both approaches in tandem. We hope the content of this review volume will help the interested reader to quickly develop an appreciation for the fundamental theories behind the molecular modeling tools and to become aware of the limits in applying these state-of-the-art methods to solve geosciences problems.

Description / Table of Contents: Over the years, volumes in this series have taken a variety of forms. Many have focused on mature fields of investigation to draw together a comprehensive body of work and provide a definitive, up to date reference. A few, however, have sought to provide enough coverage of an emerging or re-emerging field to allow the reader to identify important and exciting gaps in current knowledge and opportunities for new research. This volume falls into the later category. Our primary goal in convening the short course and assembling this text it is to invigorate future research. Early “Reviews in Mineralogy” dealt with specific groups of minerals, one (or two) volumes at a time. In contrast, this volume deals explicitly with the topic of crystal size in many different systems. Until recently, the special and complicated nature of the very smallest particles rendered them nearly impossible to study by conventional methods. Even today, the challenges associated with evaluating the size-dependence of a mineral’s bulk and surface structures, properties, and reactivity are significant. However, ongoing improvements in sophisticated characterization, theory, and data analysis make particles previously described (often inaccurately) as “amorphous” (or even more mysteriously as “x-ray amorphous”) amenable to quantitative evaluation. Thermochemical, crystal chemical, and computational chemical approaches must be combined to understand particles with diameters of 1 to 100 nanometers. Determination of …

Description / Table of Contents: Zeolites were looked upon as a geological curiosity until the latter part of the 20th century, but they are now known to be widespread throughout the world in sedimentary and igneous deposits and in soils. This volume describes their formation and occurrence in these environments. It also describes the latest information on their crystal structures and chemistry and presents entirely new information on zeolite stability and on cation exchange. Four chapters also describe applications of natural zeolites ranging from building material to high-tech refrigeration devices.

Description / Table of Contents: This volume was prepared for Short Course on Stable Isotope Geochemistry presented November 2-4, 2001 in conjunction with the annual meetings of the Geological Society of America in Boston, Massachusetts. This volume follows the 1986 Reviews in Mineralogy (Vol. 16) in approach but reflects significant changes in the field of Stable Isotope Geochemistry. In terms of new technology, new sub-disciplines, and numbers of researchers, the field has changed more in the past decade than in any other since that of its birth. Unlike the 1986 volume, which was restricted to high temperature fields, this book covers a wider range of disciplines. However, it would not be possible to fit a comprehensive review into a single volume. Our goal is to provide state-ofthe-art reviews in chosen subjects that have emerged or advanced greatly since 1986. v The field of Stable Isotope Geochemistry was born of a good idea and nurtured by technology. In 1947, Harold Urey published his calculated values of reduced partition function for oxygen isotopes and his idea (a good one!) that the fractionation of oxygen isotopes between calcite and water might provide a means to estimate the temperatures of geologic events. Building on wartime advances in electronics, Alfred Nier then designed and built the dual-inlet, gassource mass-spectrometer capable of making measurements of sufficient precision and accuracy. This basic instrument and the associated extraction techniques, mostly from the 1950s, are still in use in many labs today. These techniques have become "conventional" in the sense of traditional, and they provide the benchmark against which the accuracy of other techniques is compared. The 1986 volume was based almost exclusively on natural data obtained solely from conventional techniques. Since then, revolutionary changes in sample size, accuracy, and cost have resulted from advances in continuous flow massspectrometry, laser heating, ion microprobes, and computer automation. The impact of new technology has differed by discipline. Some areas have benefited from vastly enlarged data sets, while others have capitalized on in situ analysis and/or micro- to nanogram size samples, and others have developed because formerly intractable samples can now be analyzed. Just as Stable Isotope Geochemistry is being reborn by new good ideas, it is still being nurtured by new technology. The organization of the chapters in this book follows the didactic approach of the 2001 short course in Boston. The first three chapters present the principles and data base for equilibrium isotope fractionation and for kinetic processes of exchange. Both inorganic and biological aspects are considered. The next chapter reviews isotope compositions throughout the solar system including massindependent fractionations that are increasingly being recognized on Earth. The fifth chapter covers the primitive compositions of the mantle and subtle variations found in basalts. This is followed by three chapters on metamorphism, isotope thermometry, fluid flow, and hydrothermal alteration. The next chapter considers water cycling in the atmosphere and the ice record. And finally, there are four chapters on the carbon cycle, the sulfur cycle, organic isotope geochemistry and extinctions in the geochemical record.