Barite-Fluorite Mineralization in Southeast Sichuan, Yangtze Block, China (Modern Approaches in Solid Earth Sciences Book 23)

This book describes the mineralization process of barite-fluorite deposits in southeastern Sichuan, Yangtze Block, China. Mainly through systematic field geological surveys and detailed indoor research work, the typical barite-fluorite deposits in this area were analyzed using a variety of analysis methods such as single fluid inclusion LA-ICP-MS composition analysis, trace rare earth element analysis, H-O-S-Sr isotope analysis, F element content analysis, and Sm-Nd geochronological analysis. By in-depth analysis of the ore-forming environment, mineralization process and geological characteristics of barite-fluorite deposits, the following were determined: (1) the source of ore-forming fluids of barite-fluorite deposits and (2) the migration, concentration, enrichment, and evolution of ore-forming sources, exploring the formation mechanism of barite-fluorite deposits. Summarizing the mineralization regularity of the deposit in this area of China provides a new insight and basis for the study of similar types of deposits in the world. Foreword 1 6 Foreword 2 8 Preface 10 About the Book 12 Contents 14 About the Authors 17 List of Figures 19 List of Tables 26 Chapter 1: Introduction 28 1.1 Significance 28 1.2 State of the Art Research 29 1.2.1 State of the Art Research on Fluorite 29 Resource Status of Fluorite 30 The Global Position of Fluorite Resources in China 30 Distribution of Fluorite Resources in China 33 State of the Art Research of Fluorite Deposit Characteristics 33 Types of Fluorite Deposits 33 Genesis of Fluorite Deposits 34 Mineralization Temperature of Fluorite Deposits 35 Mineralization Age of Fluorite Deposits 35 Source of Ore-Forming Materials 37 Ore-Forming Fluid Sources 39 The Colour of Fluorite 39 1.2.2 State of the Art Research on Barite 40 Resource Status of Barite 40 The Global Status of Barite Resources in China 40 Distribution Characteristics of Barite Resources in China 41 State of the Art Research of Barite Deposits 41 Deposit Types 41 Geological Characteristics of Barite Deposits 44 Mineralization Temperature of Barite Deposits 50 Sources of Ore-Forming Materials in Barite Deposits 50 Sr and S Isotopes 50 REE Characteristics 51 1.2.3 State of the Art Research on Fluorite of the Study Area 52 1.3 The Scientific Problem 55 1.4 Research Ideas and Research Content 56 1.4.1 Research Ideas 56 1.4.2 Research Content 57 References 58 Chapter 2: Geological Setting 64 2.1 Geotectonic Setting 64 2.1.1 Paleozoic to Early Devonian Tectonic Evolution 66 2.1.2 Middle Devonian to Early Permian Tectonic Evolution 70 2.1.3 Late Permian to Middle Triassic Tectonic Evolution 74 2.1.4 Late Triassic to Early Cretaceous Tectonic Evolution 76 2.1.5 Late Cretaceous to Present Tectonic Evolution 79 2.2 Regional Stratigraphic Characteristics 80 2.2.1 Pre-Cambrian 82 2.2.2 Cambrian 84 2.2.3 Ordovician 86 2.2.4 Middle-Lower Silurian 87 2.3 Regional Structural Characteristics 88 2.3.1 Fold Ore Control Structure System 88 2.3.2 Fault Structure System 88 References 90 Chapter 3: Petrological Characteristics and Sedimentary Environment 92 3.1 Petrological Characteristics 92 3.1.1 Clastic Rocks and Shale 92 3.1.2 Carbonate 96 3.2 Sedimentary Environment 101 References 103 Chapter 4: Mineralization Belts and Geological Characteristics of Deposits 104 4.1 Distribution Characteristics of Mineralization Belts 104 4.2 Geological Characteristics of Typical Deposits 108 4.2.1 Langxi Huoshiya Barite-Fluorite Deposit 108 Strata 108 Structure 111 Ore Body Characteristics 112 Ore Characteristics 113 Ore Composition and Properties 113 Ore Texture and Structure 114 Wall Rock Alteration 115 4.2.2 Fengjia Barite-Fluorite Deposit 115 Strata 115 Structure 115 Ore Body Characteristics 117 Ore Characteristics 117 Wall Rock Alteration 118 4.2.3 Taiji Barite-Fluorite Deposit 119 Strata 119 Structure 120 Ore Body Characteristics 120 Ore Characteristics 120 Wall Rock Alteration 120 4.2.4 Honghualing Barite-Fluorite Deposit 120 Strata 122 Structure 122 Ore Body Characteristics 122 Ore Characteristics 125 Wall Rock Alteration 126 References 126 Chapter 5: Element Geochemistry 127 5.1 Sample Collection and Analysis 127 5.2 Geochemical Characteristics of Trace Elements 128 5.3 Geochemical Characteristics of REEs 134 5.3.1 Characteristics of REE in Fluorite and Barite 136 5.3.2 Characteristics of REE in Ore-Bearing Wall Rocks 138 5.4 Discussion 139 5.4.1 REE Patterns 139 5.4.2 δEu and δCe 140 5.4.3 REE Variation Diagrams 141 La/Ho Vs Y/Ho 141 Tb/Ca Vs Tb/La 141 La/Yb Vs REE 143 References 144 Chapter 6: Ore-Forming Fluids 146 6.1 Fluid Inclusion Geochemistry 147 6.1.1 Petrographic Characteristics of Fluid Inclusions 148 6.1.2 Homogenization Temperature and Salinity 150 6.1.3 Fluid Inclusion Density 154 6.2 Pressure Estimation of Fluid Inclusions 155 6.2.1 Pressure Estimation and Mineralization Depth 155 Driesner and Heinrich Equation 155 Bischoff Phase Diagram Method 156 Shao Jielian ́s Empirical Formula 157 Liu Bin ́s Isometric Equation 158 6.2.2 Degree of Erosion 159 6.2.3 Oxygen Fugacity Analysis 160 6.3 Vapor and Liquid Composition of Fluid Inclusions 160 6.3.1 Gas Phase Composition 161 6.3.2 Liquid Phase Composition 164 6.4 LA-ICP-MS Analysis of Single Fluid Inclusions 164 References 168 Chapter 7: Isotope Geochemistry 170 7.1 H-O Isotopic Characteristics 170 7.2 S Isotopic Characteristics 172 7.3 Sr Isotopic Characteristics 177 7.3.1 Sr Isotopic Compositions of the Host Rock 181 7.3.2 Sr Isotopic Composition of Fluorite and Barite 181 7.3.3 The Source of Ca and Ba 182 7.4 Sm-Nd Isotopic Characteristics 184 References 186 Chapter 8: The Source and Regularity of Mineralization 189 8.1 Source of the Ore-Forming Fluids 189 8.2 Source of the Ore-Forming Materials 193 8.3 Age of the Mineralization 194 8.4 Mineralization Period and Mineral Formation Sequence 194 8.4.1 Pre-mineralization Period 195 Sedimentary-Diagenetic Enrichment stage of the Basin 195 Precipitation and Deep-Cycle Leaching Enrichment stage 196 8.4.2 Syn-mineralization Period 197 Barite-Fluorite Mineralization Stage (I) 197 White (colorless) Coarse Grained Barite-Fluorite Substage (I-1) 197 Dark Fine-Grained Fluorite Substage (I-2) 198 Carbonate Stage (II) 199 8.4.3 Post-mineralization Period 199 8.5 Zoning of Ore Bodies and Mineralization Model 200 8.5.1 Vertical Zonation of the Ore Bodies 200 Spatial Zoning Characteristics of the Altered Roof of the Barite-Fluorite Ore Body 200 Carbonated Altered Roof 201 Silicified Alteration Top Cover 202 Spatial Zoning Characteristics of the Ore Body at the Head of Barite-Fluorite Deposits 202 Characteristics of the Upper Part of the Head Ore Body 202 Characteristics of the Lower Part of the Head Ore Body 202 Spatial Zoning Characteristics of the Upper Ore Body in Barite-Fluorite Deposits 204 Spatial Zoning Characteristics of the Middle Ore Body in Barite-Fluorite Deposits 205 Spatial Zoning Characteristics of the Lower Ore Body in Barite-Fluorite Deposits 206 Spatial Zoning Characteristics of the Tail Ore Body in Barite-Fluorite Deposits 206 8.5.2 Mineralization Model 208 8.6 Mineralization Regularity 210 8.6.1 The Spatiotemporal Evolution of the Mineralization Belt 210 8.6.2 The Temporal and Spatial Evolution of the Ore Bodies 212 References 213