Petrology And Chemistry Of Modern Big River Sands

This Proceedings volume contains papers from three symposia which were held during the 29th International Geological Congress, Kyoto, Japan, 24 August--3 September 1992. From the first symposium --- ''Metamorphic Reactions: kinetics and mass transfer'' --- 5 papers were selected for publication. One of the objectives of the symposium was to clarify the nature of reactions and mass transfer from the viewpoint of kinetics. From the ''Sandstone Petrology in Relation to Tectonics''-symposium, 10 papers were selected and revised for inclusion in this book. The articles reflect the different approaches on the relationship between sandstone composition and tectonic setting. The third symposium in this volume --- ''Evaporite and Desert Environment'' consists of 8 selected papers. The papers summarize the relationship between various desertification factors and the dynamics of different regions, and the classification of these regions according to their geological and mineralogical factors.

In the extensive field of earth sciences, with its many subdisciplines, the trans fer of knowledge is primarily established via personal communication, during meetings, by reading journal articles, or by consulting books. Because more information is available than can be assimilated, it is necessary for the individual to search selectively. Books take more time from the inception of an idea until publication than any of the other means of communication men tioned. As a consequence, their function is somewhat different. Many good books are a compilation of up to date knowledge and serve as reference or instruction manuals. Some books are a collection of previously published papers dealing with a certain topic, while others may basically provide large sets of data or examples. The Frontiers in Sedimentary Geology series was established both for stu dents and practicing earth scientists who wish to either stay abreast of the most recent ideas or developments or to become familiar with an important topic in the field of sedimentary geology. The series attempts to deal with sub jects that are in the forefront of both scientific and economic interest. The treatment of a subject in an individual volume should be a combination of topi cal, regional, and interdisciplinary approaches. Although these three terms can be defined separately, in reality they should flow into each other. A topical treatment should relate to a major category of sedimentary geology.

The first edition appeared fourteen years ago. Since then there have been significant advances in our science that warrant an updating and revision of Sand and Sandstone. The main framework of the first edition has been retained so that the reader can begin with the mineralogy and textural properties of sands and sandstones, progress through their organization and classification and their study as a body of rock, to consideration of their origin-prove nance, transportation, deposition, and lithification-and finally to their place in the stratigraphic column and the basin. The last decade has seen the rise of facies analysis based on a closer look at the stratigraphic record and the recognition of characteristic bed ding sequences that are the signatures of some geologic process-such as a prograding shallow-water delta or the migration of a point bar on an alluvial floodplain. The environment of sand deposition is more closely determined by its place in such depositional systems than by criteria based on textural characteristics-the "fingerprint" approach. Our revi sion reflects this change in thinking. As in the geological sciences as a whole, the concept of plate tectonics has required a rethinking of our older ideas about the origin and accumu lation of sediments-especially the nature of the sedimentary basins.

Several important developments in our understanding of the chemistry of weathering have occurred in the last few years: 1. There has been a major breakthrough in our understanding of the mechanisms controlling the kinetics of sil icate dissolution, and there have been major advances in computer modeling of weathering processes. 2. There has been a growing recognition of the importance of organic solutes in the weathering process, and hence of the inter-relationships between mineral weathering and the terrestrial ecosystem. 3. The impact of acid deposition ("acid rain") has been widely recognized. The processes by which acid deposition is neutral ized are closely related to the processes of normal chemical weathering; an understanding of the chemistry of weathering is thus essential for predicting the effects of acid deposition. 4. More high-qual ity data have become available on the chemical dynamics of smal I watersheds and large river systems, which represent the integrated effects of chemical weathering.

The book is structured thematically, encompassing principles, processes and products, practice and applications. Discussion of processes that control heavy mineral assemblages throughout the rock cycle are presented by leading experts, whose key-note works are followed by specialist case studies. Each work also provides details on the geology of the study area, techniques and data treatment. The high number of contributions represent the collective experience and wisdom of generations of geologists, and provide an invaluable source of references to works carried out in many parts of the world. * Presents a unique and authoritative resource of immediate relevance and practical use to the researcher and applied geologist * Contains case studies demonstrating the broad range of applications of heavy minerals in a variety of modern and ancient geological settings, and in resource exploration * Includes examples of geological problems from employing heavy mineral analysis and establishing criteria that can be applied before deciding to undertake a study