Download or read book Atlas of Alteration Assemblages Styles and Zoning in Orogenic Lode gold Deposits in a Variety of Host Rock and Metamorphic Settings written by and published by . This book was released on 1999 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydrothermal Processes and Mineral Systems written by Franco Pirajno and published by Springer Science & Business Media. This book was released on 2008-10-14 with total page 1250 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Gold in the Central Lapland Greenstone Belt written by V. Juhani Ojala and published by . This book was released on 2007 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gold in 2000 written by Steffen Gerd Hagemann and published by . This book was released on 2000 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stable Isotopes in High Temperature Geological Processes written by John W. Valley and published by Walter de Gruyter GmbH & Co KG. This book was released on 2018-12-17 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 16 of Reviews in Mineralogy inroduces to high-temperature stable isotope geochemistry and should provide an entry into the pertinent literature, as well as some understanding of the basic concepts and potential applications. The first three chapters focus on the theory and experimental data base for equilibrium, disequilibrium, and kinetics of stable isotope exchange reactions among geologically important minerals and fluids. The fourth chapter discusses the primordial oxygen isotope variations in the solar system prior to formation of the Earth, along with a discussion of isotopic anomalies in meteorites. The fifth chapter discusses isotopic variations in the Earth's mantle and the sixth chapter reviews the variations in the isotopic compositions of natural waters on our planet. In Chapters 7, 8, 9 and 10, these isotopic constraints and concepts are applied to various facets of the origin and evolution of igneous rocks, bringing in much material on radiogenic isotopes as well, because these problems require a multi-dimensional attack for their solution. In Chapters 11 and 12, the problems of hydrothermal alteration by meteoric waters and ocean water are considered, together with discussions of the physics and chemistry of hydrothermal systems and the 18O/16O history of ocean water. Finally, in Chapters 13 and 14, these concepts are applied to problems of metamorphic petrology and ore deposits, particularly with respect to the origins of the fluids involved in those processes.
Download or read book Gold Deposits in Metamorphic Rocks written by Ed DeWitt and published by . This book was released on 1990 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gold Transporting Hydrothermal Fluids in the Earth s Crust written by P.S. Garofalo and published by Geological Society of London. This book was released on 2014-09-16 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrothermal ore deposits that are exploited for gold include both gold-only deposits, such as orogenic deposits, and gold-bearing examples of the common hydrothermal deposits types that are formed around upper-crustal magmatic centres, in particular porphyry and epithermal deposits. Fluid-inclusion data have shown that ore fluids of gold-only deposits are compositionally distinct compared to fluids of other deposit types. This Special Publication includes an up-to-date summary of thermodynamic parameters of aqueous Au species at high temperatures and pressures; a dataset of fluid inclusion properties and compositions from orogenic deposits of different parts of the world; several comprehensive case studies of different types of gold deposits and their fluids from USA, Brazil, Egypt, Slovakia and Bulgaria; and numerical modelling aimed to define key parameters that affect fluid flow and gold deposition at a range of scales.
Download or read book Archean Lode Gold Deposits in Ontario written by A. C. Colvine and published by . This book was released on 1988 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Formation of Gold Deposits written by Neil Phillips and published by Springer Nature. This book was released on 2022-06-16 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the origin of gold deposits to answer questions of science and curiosity. These answers contribute in turn to the improved exploration and mining of gold. Initially there is a summary of the methods used to address the genesis of gold deposits including some of the essential science and concepts. Five basic observations follow that apply to many gold deposits and need to be considered in any genetic ideas. Magmatic processes enriching gold are discussed followed by the role of aqueous fluids during gold deposit formation at elevated temperatures and pressures. Modifying effects after deposit formation include high-grade metamorphism, retrogression, weathering, and erosion. The main types of gold deposits are then explained within the spectrum of viable genetic ideas, with informal names for these examples that include gold-only, gold-plus, Carlin, slate-belt, epithermal, porphyry, iron oxide copper gold, and Archean greenstone. Case histories are included in which the role of gold geology contributed directly to discoveries—one example is at the province-scale and another at the goldfield-scale. Unlike other books on the subject, this one addresses virtually all gold deposit types rather than focusing on one type in isolation. The primary readership includes industry geologists, senior undergraduates, postgraduates, and those with some knowledge of science and an interest in the gold industry.
Download or read book Geology and Gold Mineralization of the Gold Basin Lost Basin Mining Districts Mohave County Arizona written by Ted G. Theodore and published by . This book was released on 1987 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petrogenesis of Metamorphic Rocks written by Kurt Bucher and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metamorphic rocks are one of the three classes of rocks. Seen on a global scale they constitute the dominant material of the Earth. The understanding of the petrogenesis and significance of metamorphic of geological education. rocks is, therefore, a fundamental topic There are, of course, many different possible ways to lecture on this theme. This book addresses rock metamorphism from a relatively pragmatic view point. It has been written for the senior undergrad uate or graduate student who needs practical knowledge of how to interpret various groups of minerals found in metamorphic rocks. The book is also of interest for the non-specialist and non-petrolo gist professional who is interested in learning more about the geolo gical messages that metamorphic mineral assemblages are sending, as well as pressure and temperature conditions of formation. The book is organized into two parts. The first part introduces the different types of metamorphism, defines some names, terms and graphs used to describe metamorphic rocks, and discusses principal aspects of metamorphic processes. Part I introduces the causes of metamorphism on various scales in time and space, and some principles of chemical reactions in rocks that accompany metamorphism, but without treating these principles in detail, and presenting the thermodynamic basis for quantitative analysis of reactions and their equilibria in metamorphism. Part I also presents concepts of metamorphic grade or intensity of metamorphism, such as the metamorphic-facies concept.
Download or read book Atlas of Alteration written by Rodney Allen and published by . This book was released on 1996 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Macraes Orogenic Gold Deposit New Zealand written by Dave Craw and published by Springer. This book was released on 2016-08-10 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the nature and origin of the Macraes gold deposit. It also documents the key features of this spectacular deposit for a wide range of professionals in the resource geology community. This world-class gold deposit has been a spectacular geological and economic success story, as it has developed from a small historical gold mine in discontinuous quartz veins measuring only meters to a large-scale mine in deposits spreading over kilometres in extensive disseminated gold-bearing rock.
Download or read book The Metallogeny of Lode Gold Deposits written by Ulrich Kretschmar and published by Elsevier. This book was released on 2015-11-24 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Metallogeny of Lode Gold Deposits: A Syngenetic Perspective is a synthesis of lode gold vein forming processes, addressing the commonality in similar worldwide deposits. The book’s empirical model incorporates widely known and accepted principles of ore deposition and shows how it applies in the volcanic-sedimentary greenstone belt environment. Several chapters detail outcrop maps and photos of field occurrences and textures. The interpretations flow directly from the authors’ field work, and are coupled with analyses of underlying physical processes. Utilizing detailed geological mapping, field work, and chemical analyses as the basis of a syngenetic formation mode, the text arms readers with the tools necessary to accurately analyze and interpret new data on the subject. This includes information on decoding the significance of asymmetry in vein formation, as well as the role of lamprophyres in gold camps, how Archean geology requires integration into a lode vein formation model, and how to develop an understanding of the worldwide applicability of gold cycles to lode vein formation and exploration and how it can be applied to deposits of all ages. Presents the first book to galvanize lode gold research into a single authoritative reference Simplifies the complexity of lode gold’s underlying processes and presents valid concepts surrounding the lode gold forming environment Features color figures, illustrations, and photos that enrich the content’s focus and aid in the retention of key concepts
Download or read book Exploring Competing Gold System Models in the Valdez Creek Region Clearwater Mountains Alaska written by Jane Marguerite Suhey and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gold deposits located within the accretionary and subduction-related tectonic environment of south-central Alaska are interpreted to have formed via devolatilization of hydrous assemblages through regional metamorphism (orogenic model) or by intrusion-related hydrothermal processes (intrusion-related gold system model). The Valdez Creek mining district is located in the southern Clearwater Mountains of south-central Alaska along the intermontane-insular belt suture of the North American Cordillera. The 67-56 Ma south-vergent Valdez Creek shear zone resulted in the thrusting of North American-derived Maclaren schist (intermontane) structurally above lower greenschist-facies rocks of the Clearwater metasediments (Insular). The ~ 5km thick ductile shear zone preserves a complete inverted Barrovian metamorphic gradient ranging from lower greenschist-facies conditions in the south to upper-amphibolite-facies in the north. This event records the terminal suturing of the Wrangellia composite terrane with the North American margin. Placer gold mining and lode gold exploration is currently focused within the footwall of the Valdez Creek shear zone. The region also contains previously undated Cretaceous intrusive rocks associated with gold-in-soil geochemical anomalies. Here, competing gold system models were investigated to identify the predominant mineralization process. This information is used to improve exploration strategies in the area and further develop our understanding of gold formation in the Clearwater Mountains, Alaska. Constraining mechanisms of gold mineralization through integrating structural analysis, geochemistry, and a multiphase geochronologic framework provides a robust tool to determine dominant ore-forming mechanisms. 40Ar/39Ar and 206Pb/238U geochronological methods were used to determine the timing of gold mineralization and constrain ages of igneous rocks associated with known lode sources. Detrital gold geochemistry methods were used to compare placer gold and lode gold compositions. Bulk rock major and trace element geochemical methods were also used to evaluate a primary gold-model by investigating compositional differences of gold-like elements across the Valdez Creek shear zone. Detailed mapping and structural analysis were completed to test if gold mineralization is compatible with shear zone activity (supporting an orogenic model) or if mineralization was unrelated to regional metamorphism and overprinted by the shear zone from 67-56 Ma (supporting an intrusion-related gold system model). The 206Pb/238U zircon data collected from the alkali pluton suite and the placer system indicates gold-hosting veins were localized within and adjacent to alkaline plutons in the region. These data also indicate that detritus in the placer system was locally derived. White mica 40Ar/39Ar geochronology integration ages from undeformed gold-bearing quartz veins proximal to intrusions supports a young mineralization age for gold between 62.11 Ma to 66.58 Ma. Similarities in gold chemistry were also identified within placer gold samples collected from current mining operations and a lode gold location within the catchment. Structural observations show gold-bearing mineralization in quartz veins is likely synchronous with the penetrative deformation associated with the Valdez Creek shear zone. Discrete and network vein orientations throughout the shear zone have geometries compatible with top-to-the-south shear sense of the Valdez Creek shear zone. These results are compatible with a local gold lode source for the Valdez Creek placer deposit that formed coeval with the Valdez Creek shear zone. Bulk rock major and trace element geochemistry results from across the Valdez Creek shear zone metamorphic gradient show a systematic decrease in As, Cu, Ni, Zn, Pb, and Au across the greenschist-amphibolite facies transition indicating that auriferous fluids may have been derived from the shear zone. We hypothesize that metamorphic fluids generated from the dehydroxylation of chlorite occurred simultaneously with shearing along the Valdez Creek shear zone. In this system, auriferous fluids were likely concentrated within or proximal to rigid intrusion(s) in the footwall of the shear zone, coinciding with vein development and fluid channelization, similar in process to the Juneau Gold Belt.
Download or read book Gold metallogeny and exploration written by R. P. Foster and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within the last decade, the high and continuing demand for gold has prompted a global gold rush on a scale never before seen, not even in the heady days of Ballarat, California and the Yukon. Gold is being sought on every continent and, with very few exceptions, in every country around the world. Such interest and fierce competition has demanded considerable innovation and improvement in exploration techniques paralleled by a rapid expansion of the geological database and consequent genetic modelling for the many different types of gold deposits now recognized. This proliferation of data has swamped the literature and left explorationist and academic alike unable to sift more than a small proportion of the accumulating information. This new book represents an attempt to address this major problem by providing succinct syntheses ofall major aspects ofgold metallogeny and exploration, ranging from the chemical distribution of gold in the Earth's crust, and the hydrothermal chemistry of gold, to Archaean and Phanerozoic lode deposits, epithermal environments, chemical sediments, and placer deposits, and culminates in chapters devoted to geochemical and geophysical exploration, and the economics of gold deposits. Each chapter is written by geoscientists who are acknowledged internationally in their respective fields, thus guaranteeing a broad yet up-to-date coverage. In addition, each chapter is accompanied by reference lists which provide readers with access to the most pertinent and useful publications.
Download or read book Southwest Pacific Rim Gold copper Systems written by Greg John Corbett and published by . This book was released on 1998 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
