W-Sn Skarn Deposits


Book Description

Intended as a reference for the academically-oriented geologist as well as the practising economic geologist, this book is concerned with the study of skarn deposits having anomalously high tin or tungsten contents, or both. Unlike many other books on economic geology, both economic W-Sn skarns and non-economic examples are covered, in order to enable the academically-oriented reader to grasp the full range of such deposits, and also to aid the economic geologist in distinguishing between W-Sn skarns having economic potential and those which do not.W-Sn skarns are notoriously complex, containing a wide range of textures, grain sizes, mineral assemblages, bulk compositions and structures. The lack of a sufficiently detailed data base, coupled with some unsupportable genetic models, has led to many misunderstandings and has often resulted in needless expenditure and effort on fruitless mineral exploration. Thus, the first aim of this book is simply to provide an adequate data base with sufficient references to enable an interested worker to define a skarn deposit and know where to find additional information on similar examples. To aid this, as much data as possible is presented as tables and diagrams.The second aim of the book is to show the reader how to separate skarn rocks found in W-Sn-bearing environments into those produced by metamorphic, isochemical processes (metamorphic skarns) which are uneconomic, and those produced by the introduction and exchange of components from an ore solution (ore skarn). W-Sn skarns are also separated into genetically logical subdivisions so that, if a deposit or a specific geological environment can be identified, then skarn zonation or the potential of finding specific skarn types can be predicted. This is particularly important to the practising exploration geologist because often only a small part of a skarn or only certain skarn types contain economic mineralization.In addition, the book provides an insight into how to assess where mineralogical complications may occur, especially with respect to Sn-skarns, and in which environments such complications may be expected. It also provides enough information for the reader to be able to conceptualize suitable models for W-Sn skarns based on primary data.




Skarns in British Columbia


Book Description

Skarns in British Columbia have historically been important sources of iron, tungsten, copper, and gold. This publication begins with an introduction on skarn terminology and the problems of skarn identification. It then reviews a genetic model of skarn formation and presents descriptive profiles of eight types of skarn deposits; describes the database of at least 735 skarn occurrences in the province, and the number and distribution of skarns in British Columbia according to their associations, class, age, and distribution; and notes the ages of British Columbia skarns and the total production of various metals extracted from British Columbia skarns. Subsequent sections provide information on assays and metal ratios of mineralized skarns, skarn mineralogy, skarn mineral chemistry, chemistry of skarn-related intrusions, and the mapping and evaluation of skarns. The appendix contains a listing of 735 skarn occurrences in British Columbia, giving deposit name, MINFILE number, latitude/longitude, elements and minerals present, and associated rocks and their ages.




Hydrothermal Processes and Mineral Systems


Book Description

Hydrothermal processes on Earth have played an important role in the evolution of our planet. These processes link the lithosphere, hydrosphere and biosphere in continuously evolving dynamic systems. Terrestrial hydrothermal processes have been active since water condensed to form the hydrosphere, most probably from about 4.4 Ga. The circulation of hot aqueous solution (hydrothermal systems) at, and below, the Earth’s surface is ultimately driven by magmatic heat. This book presents an in-depth review of hydrothermal proceses and systems that form beneath the oceans and in intracontinental rifts, continental margins and magmatic arcs. The interaction of hydrothermal fluids with rockwalls, the hydrophere and the biophere, together with changes in their composition through time and space, contribute to the formation of a wide range of mineral deposit types and associated wallrock alteration. On Earth, sites of hydrothermal activity support varied ecosystems based on a range of chemotrophic microorganisms both at surface and in the subsurface. This book also provides an overview of hydrothermal systems associated with meteorite impacts and explores the possibility that hydrothermal processes operate on other terrestrial planets, such as Mars, or satellites of the outer planets such as Titan and Europa. Possible analogues of extraterrestrial putative hydrothermal processes pose the intriguing question of whether primitive life, as we know it, may exist or existed in these planetary bodies. Audience: This volume will be of interest to scientists and researchers in geosciences and life sciences departments, as well as to professionals and scientists involved in mining and mineral exploration.










Understanding Mineral Deposits


Book Description

Mineral deposits have supplied useful or valuable material for human consumption long before they became objects of scientific curiosity or commercial exploitation. In fact, the earliest human interest in rocks was probably because of the easily accessible, useful (e. g. , red pigment in the form of earthy hematite) or valuable (e. g. , native gold and gemstones) materials they contained at places. In modem times, the study of mineral deposits has evolved into an applied science employing detailed field observations, sophisticated laboratory techniques for additional information, and computer modeling to build complex hypotheses. Understanding concepts that would someday help geologists to find new mineral deposits or exploit the known ones more efficiently have always been, and will continue to be, at the core of any course on mineral deposits, but it is a fascinating subject in its own right, even for students who do not intend to be professional economic geologists. I believe that a course on mineral deposits should be designed as a "capstone course" that illustrates a comprehensive application of concepts from many other disciplines in geology (mineralogy, stratigraphy and sedimentation, structure and tectonics, petrology, geochemistry, paleontology, geomorphology, etc. ). This book is intended as a text for such an introductory course in economic geology, primarily for senior undergraduate and graduate students in colleges and universities. It should also serve as a useful information resource for professional economic geologists.










Hydrothermal Mineral Deposits


Book Description

This book is intended primarily for exploration geologists and post graduate students attending specialist courses in mineral exploration. Exploration geologists are engaged not only in the search for new mineral deposits, but also in the extension and re-assessment of existing ones. To succeed in these tasks, the exploration geologist is required to be a "generalist" of the Earth sciences rather than a specialist. The exploration geologist needs to be familiar with most aspects of the geology of ore deposits, and detailed knowledge as well as experience play an all important role in the successful exploration for mineral commodities. In order to achieve this, it is essential that the exploration geologist be up to date with the latest developments in the evolution of concepts and ideas in the Earth sciences. This is no easy task, as thousands of publications appear every year in an ever increasing number of journals, periodicals and books. For this reason it is also difficult, at times, to locate appropriate references on a particular mineral deposit type, although this problem is alleviated by the existence of large bibliographic data bases of geological records, abstracts and papers on computers. During my teaching to explorationists and, indeed, during my years of work as an explorationist, the necessity of having a text dealing with the fundamental aspects of hydrothermal mineral deposits has always been compelling. Metallic mineral deposits can be categorised into three great families, namely: (I) magmatic; (2) sedimentary and residual; (3) hydrothermal.




Polymetallic Metallogenic System


Book Description

Within the last decade, the high and continuing demand for precious and base metals, as well as critical elements, has prompted a global rush on a scale never before seen. This eventually resulted in the demand for considerable innovation and improvement in mineral deposit genetic modelling and ore formation regimes for the many different types of gold deposits, now recognized, and paralleled by the wide employment of exploration techniques and a rapid expansion of geological databases. This Special Issue will show case studies of porphyry polymetal systems, orogenic gold formations, water–rock reaction, ore-forming structure evolution, mineralogy and petrology of ore deposit, ore formation regime, geochronology and geochemistry of ore deposit, ore-forming evolution, mineral exploration and cutting-edge technology in ore deposit study.