中国煤层气地质与开发基础理论（英文版）

Contents

Foreword 1 i

Foreword 2 iii

Preface v

Chapter 1 Status Quo and Research of CBM Exploration and Development 1

1.1 CBM Development Status Quo in Some Countries 1

1.1.1 CBM industry development in the United States 1

1.1.2 CBM industry development in other countries 3

1.2 CBM Industry Development Course in China—Theory and Technology Status 5

1.2.1 Development course 5

1.2.2 Progress in basic research 6

1.2.3 Status and progress of CBM exploration and development technology in China 9

1.3 Key Scientific and Technological Challenges in CBM Exploration and Development in China 11

References 12

Chapter 2 Genesis and Criteria of CBM 14

2.1 Geochemical Characteristics of CBM and Its Difference from Natural Gas 14

2.1.1 Sample testing method 14

2.1.2 Composition and basic characteristics 14

2.1.3 Composition and distribution of isotope 15

2.1.4 Difference and specificity of isotope composition 16

2.2 Control Factors on Carbon Isotope Indicator 17

2.2.1 Desorption and fractionation of methane carbon isotope 17

2.2.2 Impact of secondary biogenic gas on methane carbon isotope composition 19

2.2.3 Impact of microscopic composition of coal rock on methane carbon isotope composition 20

2.3 Genetic Classification and Geochemical Tracer System 20

2.3.1 Primary biogenic CBM 21

2.3.2 Thermally degraded CBM 22

2.3.3 Thermally cracked CBM 24

2.3.4 Secondary biogenic CBM 26

2.3.5 Mixed CBM 28

2.3.6 Tracer indicator system 32

2.4 Characteristics and Formation Mechanism of Secondary Biogenic CBM 33

2.4.1 Characteristics 33

2.4.2 Organic geochemistry and microbial degradation 33

References 46

Chapter 3 Characterization and Controlling Factors of CBM Reservoirs 49

3.1 CBM Reservoir Space 49

3.1.1 Pore system 49

3.1.2 Fracture system 55

3.2 Characterization and Mathematical Model of Favorable Coal Reservoirs 60

3.2.1 Pore system model 60

3.2.2 Heterogeneous models of CBM reservoir 69

3.3 Forming Mechanism and Controlling Factors of Favorable Coal Reservoirs 73

3.3.1 Coal diagenesis 73

3.3.2 Changes in porosity and permeability during coalification 81

3.3.3 Structural stress and strain response 84

3.3.4 Control of basin evolution on coal reservoir physical properties 92

References 95

Chapter 4 Coal Absorption Characteristics and Model under Reservoir Conditions 97

4.1 Experimental Study on Methane Absorption Characteristics under the Combined Influences of

Temperature and Pressure 98

4.1.1 Isothermal absorption experiment 98

4.1.2 Temperature-variable and pressure-variable absorption experiment 99

4.2 Absorption Characteristics of Coal under Formation Conditions 101

4.2.1 Effect of temperature on coal absorption capacity 101

4.2.2 Effects of temperature and pressure on coal absorption capacity 102

4.2.3 Change mechanism of adsorption capacity under reservoir conditions 106

4.3 Adsorption Model under Reservoir Conditions 107

4.3.1 Characteristic curve of methane adsorption 107

4.3.2 High-pressure isothermal adsorption curve and its correction to k value 108

4.3.3 Absorption model 111

4.4 Verification and Application of Models 112

4.4.1 Verified models by isothermal adsorption experiments 112

4.4.2 Temperature- and pressure-variable experiment results and models 114

4.4.3 Coal adsorption capacity in Qinshui Basin 116

4.4.4 Scientific and applied values 119

References 120

Chapter 5 Dynamic Conditions and Accumulation/Diffusion Mechanism of CBM 121

5.1 Structural Dynamics for CBM Accumulation 121

5.1.1 Structural evolution laid the foundation for CBM accumulation 121

5.1.2 Structural differentiation causes complicated dynamic conditions 125

5.1.3 Transformation from tectonic dynamics on coal seams controls permeable CBM zones 126

5.1.4 Combined structural dynamic conditions control the basic pattern of CBM accumulation and distribution 129

5.2 Thermal Dynamic Conditions and Accumulation/Diffusion History of CBM 129

5.2.1 Thermal history of Carboniferous-Permian coal seams 129

5.2.2 Middle Yanshanian tectonic thermal event and its thermodynamic source 132

5.2.3 Numerical simulation of CBM accumulation/diffusion history 134

5.2.4 Control of thermodynamic conditions on CBM accumulation 141

5.3 Control and Mechanism of Underground Hydrodynamic System on CBM Accumulation and Diffusion 141

5.3.1 Hydrogeological unit boundary and its internal structural differences and characteristics of CBM accumulation and diffusion 141

5.3.2 Underground hydrodynamics zoning and CBM-bearing characteristics 145

5.3.3 Groundwater geochemical field and CBM preservation conditions 148

5.3.4 Groundwater head height and gas-bearing properties 150

5.3.5 Control effect of groundwater dynamic conditions and its manifestation 153

5.3.6 Relationship between hydrodynamic conditions and CBM enrichment 155

5.4 Coup