Latest Ordovician to Early Silurian Shale Gas Strata of the Yangtze Region, China

This book presents the accumulated data and current state of geological knowledge on China’s main shale gas fields. It addresses a broad range of topics, including the geological setting, reference sections and published boreholes, lithostratigraphy, biostratigraphy and chronostratigraphy, sedimentology and sequence stratigraphy of the late Ordovician to early Silurian, spatial and temporal distribution patterns and environmental changes in the black shales of the Wufeng and Lungmachi formations, numerical analysis of the Wufengian and Lungmachian Total Organic Carbon (TOC), late Ordovician to early Silurian bentonites of the Yangtze region, and a graptolite atlas of the Wufeng and Lungmachi formations. Given its scope, the book represents a valuable asset for researchers and petroleum engineers alike. Preface References Contents List of Main Authors 1 Introduction Abstract 1.1 Shale Gas Development in the United States 1.1.1 Scientific Exploration Stage (1821–1996) 1.1.2 Technological Breakthrough Stage (1997–2003) 1.1.3 Leapfrog Development Stage (Since 2004) 1.2 Major Shale Gas Fields in the World 1.3 Shale Gas Development in China 1.3.1 Cooperation and Reference Stage (2005–2009) 1.3.2 Exploration and Appraisal Stage (2010–2013) 1.3.3 Scale Production Construction Stage (Since 2014) References 2 Geological Setting of the Ordovician and Silurian Strata of the Yangtze Platform Abstract References 3 Ordovician to Silurian Shale Gas-Bearing Strata from the Yangtze Region Abstract 3.1 Upper Yangtze: Sichuan Basin and Periphery 3.2 Middle Yangtze: Three Gorges Region 3.3 Lower Yangtze Platform and Chiangnan Transitional Belt References 4 Distribution Pattern of the Ordovician–Silurian Shale Gas-Bearing Strata in the Yangtze Region Abstract 4.1 Sweet Beds and Their Distribution of the Ordovician to Silurian Shale Gas Strata in the Yangtze Region 4.2 Early Silurian Disaster Graptolites and Their Rich Organic Horizons in the Yangtze Region 4.3 Shale Gas Enrichment and Highly Productive Interval in the Yangtze Region 4.4 Case Study of Weiyuan–Changning Shale Gas Field 4.4.1 Organic Matter Abundance 4.4.2 Organic Matter Type 4.4.3 Organic Matter Maturity (Ro) 4.4.4 Mineral Composition 4.4.5 Physical Properties of Reservoirs 4.4.6 Rock Mechanical Properties 4.4.7 Reservoir Pressure and Gas Content 4.4.8 Favorable Reservoir Distribution 4.5 Case Study of Fuling Shale Gas Field 4.5.1 Organic Matter Abundance 4.5.2 Organic Matter Type 4.5.3 Organic Matter Maturity (Ro) 4.5.4 Lithology and Mineral Composition 4.5.5 Physical Properties of Reservoir 4.5.6 Reservoir Pressure and Gas Content References 5 Regional and Global Correlation of the Latest Ordovician to Early Silurian Shale Gas-Bearing Strata Abstract 5.1 Regional Correlation of the Wufeng and Lungmachi Formations in the Yangtze Region 5.1.1 N–A Line Crossing the Yangtze Platform from West to East 5.1.2 E–F Line Crossing the Upper–Middle Yangtze Platform 5.1.3 D–J Line of the Upper Yangtze Region 5.1.4 Y–S Line from Northeast Yunnan to South Sichuan 5.1.5 Black Shales of the Wufeng and Kaochiapien Formations in the Lower Yangtze Region and Its Eastward Extension to the South Yellow Sea 5.1.6 Ordovician and Silurian Black Shales Along the East Side of the Kham–Dian Old Land 5.1.7 Black Shale of the Jenhochiao Formation from West Yunnan 5.2 A Global Correlation of Two Black Shales Through the Ordovician and Silurian Boundary 5.2.1 Peri-Gondwana 5.2.2 Kazakhstan and Uzbekistan 5.2.3 Siberia 5.2.4 Baltic Countries 5.2.5 Avalonia 5.2.6 Laurentian Continent and Its Periphery References 6 Paleogeography and Paleoenvironment Across the Ordovician–Silurian Transition in the Yangtze Region Abstract 6.1 Research History 6.2 Distribution Patterns of Black Shales During the Ordovician–Silurian Transition in South China 6.2.1 Geological Setting 6.2.2 Lithofacies and Biofacies from the Late Katian to Early Hirnantian 6.2.3 Lithofacies and Biofacies in the Middle Hirnantian 6.2.4 Lithofacies and Biofacies from the Late Hirnantian to Aeronian 6.3 Microfacies Analyses of the Shale Gas Drill Cores in Weiyuan and Luzhou Areas 6.3.1 Core Lu205 6.3.2 Core Lu202 6.3.3 Core W210 6.3.4 Core W231 6.3.5 Core W204 6.4 Sedimentary Processes During the Late Ordovician to Early Silurian 6.4.1 Transition Between the Linhsiang Formation and the Wufeng Formation 6.4.2 Depositional Processes of the Kuanyinchiao Bed 6.4.3 Deposition of Lungmachi Formation 6.5 Bioevents and Environmental Change from the Late Ordovician to Early Silurian 6.5.1 Global Cooling and Sea Level Changes 6.5.2 Ocean Redox Changes 6.5.3 Volcanic Events 6.5.4 Paleogeography References 7 Gamma Log Responses Through the Ordovician–Silurian Black Shale Graptolite Zonal Succession in the Middle and Upper Yangtze Regions Abstract 7.1 Theoretical Basis 7.1.1 Primary Formations 7.1.2 Geologic Information Recorded in GR Logs 7.2 Curve Characteristics of GR Logs in Black Shale Graptolite Zones 7.2.1 Wulong–Wuxi Area 7.2.2 Weiyuan–Yongchuan Area 7.2.3 Changning–Zhaotong Area 7.2.4 Yichang–Laifeng Area 7.3 Global Nature of the GR 7.3.1 The Comparison of Black Shale Gamma-Ray Curves from the Middle and Upper Yangtze Regions and North Africa 7.3.2 The Relationship Between Gamma-Ray Curves and Carbon Isotope Chemostratigraphy of the Ordovician–Silurian Black Shale 7.4 Correlation Between the Hirnantian Isotope Carbon Excursion and Graptolite Biozones in the Ordovician–Silurian Transition of the Xike-1 Drillcore in Guizhou References 8 Volcanic Ash Deposition and Organic Matter Enrichment in the Black Shales of the Wufeng–Lungmachi Formations in the Yangtze Region Abstract 8.1 Study Background 8.2 Overview of the Geologic Setting and Deposition of Volcanic Ash 8.3 Study Method and Sample Collection 8.4 Characteristics and Source of Volcanic Ash (K-Bentonite) 8.5 Contribution of Volcanic Ash Deposits to the Enrichment of Organic Matter 8.5.1 Differential Enrichment of Organic Matter in Volcanic-Ash Bearing Shale and Normally Deposited Shale 8.5.2 Influence of Volcanic Ash Deposits on Enrichment of Organic Matter 8.6 Prospecting References Appendix: Plates and ExplanationAppendix: Reference