Au, U, Fe, Mn, Hg, Sb, W, and P Deposits

Chapter 1. Gold in the Proterozoic Sediments of South Africa: Systems, Paradigms, and Models Introduction Gold Mineralization in South Africa South Africa's Place as a Mineral Producer Geological Eras and Mineral Production Gold in Time and Space Systems, Paradigms, and Models Paradigms of Sedimentary Gold Model of a Source Area Models of Transfer Systems Models of Depositories Stratigraphic Models Model of a Transvaal-Type Goldfield Model of a Witwatersrand-Type Goldfield Models of Gold in Time Tectonic Elevation Model Algal Activity Model Ground-Rules for Gold Prospecting Note Added in Proof ReferencesChapter 2. The Nature of the Witwatersrand Gold-Uranium Deposits Introduction The Economic Significance of the Witwatersrand Basin The Witwatersrand Basin in Time and Space Age of the Witwatersrand Strata Proterozoic Basins and the Pattern of Crustal Evolution The Architecture of the Witwatersrand Basin Structure and Components Pattern of Folding Pattern of Faulting Source of Wealth in the Witwatersrand Basin Stratigraphy and Lithology Succession and Thickness Nature of Components Dykes and Sills Sedimentology Depositional Isopachs Fluvial Fans Vertical Distribution of Mineralized Horizons The Nature of the Mineralization Production of Gold and Uranium Types of Reefs Composition of Conglomerates Mineralogy of the Reefs Chemistry of the Reefs Relationships Between Components Grain Size of Gold, Uranium, and Platinoids The Characteristics of a Goldfield Processes of Development Final Responses to Processes Sequential Development of Adjacent Fans Progressive Development of a Goldfield The Source of the Gold and Uranium ReferencesChapter 3. Origin of Western-States Type Uranium Mineralization Introduction Tectonic Conditions Sedimentation Braided-Stream Fluvial System Coarse-Grained Meanderbelt Fine-Grained Meanderbelt Sedimentary Environment, Paleoclimate and Diagenesis Mineralization and Alteration Geochemical-Cell Concept Geochemical-Cell Reaction Physical and Chemical Conditions Character of Alteration Mineral Zoning Cell Growth and Shape Modification of Geochemical-Cell Development Time of Mineralization Source of Mineralization Genetic Model Discussion Topics for Future Research Notes Added in Proof ReferencesChapter 4. Origin of the Precambrian Banded Iron-Formations Introduction Terminology and Definition of Iron-Formation Regional Geologic Distribution Ages of Precambrian Banded Iron-Formations Geologieal setting Depositional Environments Sedimentary Facies of Iron-Formations Sedimentary Structures Diagenetic and Metamorphic Alterations of the Mineral Phases Organic Remains Chemical Composition Similarities and Differences Between Banded and Oolitic Iron-Formations Hypotheses of Origin Environments of Deposition Source of Iron and Silica Transport, Deposition and Banding Conclusions Acknowledgements ReferencesChapter 5. Aspects of the Sedimentary Petrology of Cherty Iron-Formation Introduction Definition and General Description Terminology Sedimentary Features Sedimentary Textures Sedimentary Structures Organo-Sedimentary Textures and Structures Classification Diagenesis Syn-Sedimentary Deformation Shrinkage (Syneresis) Features Compaction Concretionary Bodies Solution and Solution-Collapse Features Stylolites Crystallization Textures Quartz in Matrix Cherts Quartz of Cement Chert Iron-Minerals Physico-Chemistry of Iron-Mineral Diagenesis Paleogeographic Analysis Lake Superior-Type I.Fs Algoma-Type Iron-Formations Special Problems of Iron-Formation Paleogeography Depth-Control of Iron-Mineral Facies Tectonic Control of Iron-Formation Deposition Origin of Cherty Iron-Formations Transport of Iron and Silica Direct-Precipitation Hypotheses Replacement Hypotheses Summary and Conclusions Acknowledgements ReferencesChapter 6. Genetic Problems and Environmental Features of Volcano-Sedimentary Ironore Deposits of the Lahn-Dill Type Introduction General Diagnostic Statement Geological Setting Regional and Stratigraphic Distribution Geotectonic and Paleogeographic Framework Depositional Environment of the Volcano-Sedimentary Iron Ores Sedimentary Facies of the Volcano-Sedimentary Iron Ores Mineralogical Facies of the Volcano-Sedimentary Iron Ores Chemical Composition of the Volcano-Sedimentary Iron Ores The Origin of Volcano-Sedimentary Iron Ores Hypotheses of Origin Actualistic Examples of the Formation of Iron-Rich Sediments by Volcanic Processes Similarities and Differences Between the Lahn-Dill Type and Other Types of Sedimentary Iron Formations The Relation of Volcano-Sedimentary Iron Ores To Other Syngenetic Metal Mineralizations in Geosynclinal Environments Possible Source of Iron and Silica in Ophiolitic Geosynclinal Volcanism Conclusions Acknowledgement ReferencesChapter 7. Deep-Sea Manganese Nodules Historical Introduction Distribution of Manganese Nodules in the World's Oceans Regional Distribution Sedimentation Rate Availability of Potential Nucleating Agents Age Bottom Current Velocity Biological Activity Redox Conditions Localised Distribution Distribution with Depth Geochemistry Compositional Variations Within Individual Nodules Localised Variations in Composition Regional Variations in Composition Mineralogy Internal Structure Determination of Valency States Rates and Mechanisms of Accretion Nodules Thermochemical Considerations Acknowledgements ReferencesChapter 8. Freshwater Ferromanganese Deposits Introduction Geologic Setting Occurrence and Morphology of Freshwater Ferromanganese Oxides Coatings Crusts Nodules Dispersed Ferromanganese Oxides Sediment Types Associated with Ferromanganese Nodules Chemical Composition of Freshwater Ferromanganese Oxides Iron/Manganese Ratios Major-Element Chemistry Minor-Element Chemistry Regional Variability in Nodule Composition Mineralogy Comparison Between Marine and Freshwater Nodules Mobilization/Precipitation of Iron and Manganese in the Sedimentary Environment Aqueous Geochemistry of Iron and Manganese Transport of Iron and Manganese Interaction Between Source Waters and Lake Waters Deposition of Iron and Manganese Oxyhydroxides Theories of Origin Historical Development Precipitation From Overlying Water Diagenetic Remobilization Ferromanganese Oxide Precipitation Mechanism(S) Summary and Conclusions ReferencesChapter 9. Ancient Manganese Deposits Introduction Nonvolcanogenic-Sedimentary Manganese Deposits Manganese Deposits Associated with Terrigenous Formations Manganese Deposits Associated with Carbonate Formation Manganese Deposits Associated with Iron-Formation Fossil Manganese and Iron-Manganese Nodules Sedimentary Manganese Ores and Stromatolites Volcanogenic-Sedimentary Manganese Deposits Deposits of Olympic Peninsula Type Deposits of Noda Tamagawa Type Deposits of West African Type Deposits of Langban Type Deposits of Karadzhal Type Summary and Conclusion Acknowledgements ReferencesChapter 10. The Strata-Bound Cinnabar-Stibnite-Scheelite Deposits (Discussed with Examples From the Mediterranean Region) Introduction Sardinia Turkey Conclusions The Eastern Alps Spain Conclusions ReferencesChapter 11. Sedimentary Phosphate Deposits Introduction Distribution of Phosphate Deposits Types of Phosphate Deposits "Geosynclinal" Phosphorites "Platform" Phosphorites Weathered and Residual Phosphorites Petrology of Phosphorites Phosphatic Nodules Phosphatic Grains and Pellets Non-Pelletal Phosphate Geochemistry of Phosphorites The Genesis of Phosphorites Conclusions ReferencesReferences Index Part IISubject Index Part II