Lamprophyres


Book Description

Following their recognition by GUmbel (1874), lamprophyres were treated for an entire century as little more than obscure curiosities. Although this situation has changed recently, with a flowering of publications and active workers, lamprophyres remain almost the only group of igneous rocks which have not yet received attention in a dedicated monograph. In five exploratory reviews (1977-1987), the writer aimed to set out what was known about these rocks. The lUGS Subcommission on igneous rock systematics had meanwhile presented its nomenclatural framework (Streckeisen 1979). All this has now been overtaken by a recent explosion of interest, epitomized not least by lamprophyres' greater prominence in the 4th International Kimberlite Conference Proceedings. More data have become available since 1985 than over the entire previous century, and it is obviously impossible for such an extraordinary outpouring to be fully reviewed in this first, preliminary book. At the risk of dissatisfying some readers, therefore, this book concentrates on factual matters, and on a broad overview rather than minutiae. Because not even a world map of known lamprophyres was previously available, almost half the book is deliberately taken up by the first global lamprophyre compilation, and its commensurately extensive Bibliography. Such a compendium of largely objective information is believed to be of more immediate interest and lasting value than a premature pottage of petrogenetic polemic. Chapters 1-7 bring previous studies up to date, and concentrate on factual information.




Lamprophyres


Book Description

Following their recognition by Gumbel (1874), lamprophyres were treated for an entire century as little more than obscure curiosities. Although this situation has changed recently, with a flowering of publications and active workers, lamprophyres remain almost the only group of igneous rocks which have not yet received attention in a dedicated monograph. In five exploratory reviews (1977-1987), the writer aimed to set out what was known about these rocks. The lUGS Subcommission on igneous rock systematics had meanwhile presented its nomenclatural framework (Streckeisen 1979). All this has now been overtaken by a recent explosion of interest, epitomized not least by lamprophyres' greater prominence in the 4th International Kimberlite Conference Proceedings. More data have become available since 1985 than over the entire previous century, and it is obviously impossible for such an extraordinary outpouring to be fully reviewed in this first, preliminary book. At the risk of dissatisfying some readers, therefore, this book concentrates on factual matters, and on a broad overview rather than minutiae. Because not even a world map of known lamprophyres was previously available, almost half the book is deliberately taken up by the first global lamprophyre compilation, and its commensurately extensive Bibliography. Such a compendium of largely objective information is believed to be of more immediate interest and lasting value than a premature pottage of petrogenetic polemic. Chapters 1-7 bring previous studies up to date, and concentrate on factual information.




Evolution of Archean Crust and Early Life


Book Description

This book presents an integrated approach to the study of the evolution of the Archean lithosphere, biosphere and atmosphere, and as such it is a unique contribution to our understanding of the early Earth and life. The structural and geochemical make-up of both the oceanic and continental crust of the Archean Earth is documented in some case studies of various cratons, and the implications of the Phanerozoic plate and plume tectonic processes for the Archean geology are discussed in several chapters in the book. All chapters are process-oriented and data-rich, and reflect the most recent knowledge and information on the Archean Earth. The interdisciplinary approach of examining the evolution of the Archean crust, oceans, and life that we adopt in this book sets it apart from previous publications on Precambrian geology. The book will be attractive to researchers in academia and in industry, and to senior undergraduate students, graduate students and faculty in earth and natural sciences.




Archean Crustal Evolution


Book Description

The integration of Tectonics/Geochemistry, up-to-date reviews by leading scientists as well as a broad topical coverage of the Archean, are some of the features of this particular volume. As geochronology has progressed in the last 20 years, the Archean has continued to attract interest. Advancements in the understanding of Archean crustal and mantle evolution have progressed rapidly since the first International Archean Symposium in Western Australia (1970). The landmark for the Archean was the NATO Advanced Study Institute at Leicester (1975). At this meeting the Archean truly "came of age". Investigators from many different disciplines focused their expertise on the early history of the earth. For the first time, the nature of the atmosphere, oceans, and life during the Archean was an important part of an Archean symposium. During the most recent Archean Symposium in Perth in 1990, there was a shift in interest from field and trace element data to the new rapidly evolving high-precision U/Pb geochronology of Archean rocks and to detailed structural studies of both low and high grade Archean terrains. The terrane concept so widely applied to the Phanerozoic was proposed for the Archean Yilgarn Province in Western Australia and is now widely accepted for the Archean (as evident by the articles in this book). Plate tectonics is now widely accepted as the principal process that controls the history of continents and oceans. There are, though, well substantiated differences between Archean and post-Archean rocks that indicate that Archean tectonic regimes must have differed in some respects from modern ones. The question of how and to what degree did Archean plate tectonics differ from modern plate tectonics is treated in many of the chapters of this book. Altogether, the editor has presented a selection of articles that provide a fascinating insight into the latest observations in this field.




Lamprophyres, Lamproites and Related Rocks


Book Description

Paleoproterozoic to Cenozoic lamprophyres, lamproites & related rock types are volatile-rich mafic magmatic rocks with a unique potential for the investigation of processes affecting mantle reservoirs. They originated from primary mantle-derived melts that intruded both cratons & offcraton regions, which were parts of former supercontinents - Columbia, Rodinia & Gondwana-Pangea. Well-known for hosting economic minerals & elements such as diamonds, base metals, gold & platinum-group elements, they are also significant for our understanding of deep-mantle processes, such as mantle metasomatism & mantle plume-lithosphere interactions, as well as large-scale geodynamic processes, such as subduction-related tectonics, & supercontinent amalgamation & break-up. This text provides a timely overview of the state-of-the-art & recent advances as achieved by various research groups around the world.