Understanding Downhole Microseismic Data Analysis : With Applications in Hydraulic Fracture Monitoring

This book is designed as an excellent resource text for students and professionals, providing an in-depth overview of the theory and applications of downhole microseismic monitoring of hydraulic fracturing. The readers will benefit greatly from the detailed explanation on the processes and workflows involved in the acquisition design modeling, processing and interpretation of microseismic data. Preface 5 Acknowledgements 7 Contents 8 Abbreviations 11 Symbols 12 List of Figures 14 1 Introduction 23 1.1 Unconventional Reservoirs 23 1.2 Hydraulic Fracturing 27 1.3 Microseismic Monitoring 31 1.4 Key Points 36 References 37 2 Survey Design and Microseismic Data Acquisition 42 2.1 Key Information for Pre-survey Design Modeling 44 2.2 Waveform and Traveltime Modeling Tools 45 2.3 Expected Microseismicity 46 2.4 Event Detectability 49 2.5 Size and Location of the Receiver Arrays 55 2.6 Field Execution of a Microseismic Survey 70 2.7 Key Points 71 References 72 3 Microseismic Data Processing 75 3.1 Data Loading 79 3.2 Filtering 81 3.2.1 Time-Frequency Thresholding 83 3.2.2 Polarization Filtering 86 3.3 Event Detection 87 3.3.1 The STA/LTA Method 90 3.3.2 The Waveform Correlation Method 92 3.4 Arrival-Time Picking 95 3.4.1 The AIC Picker 95 3.4.2 The Kurtosis Picker 97 3.4.3 The Correlation Picker 98 3.5 Receiver Orientation 102 3.5.1 The Maximum Energy Method 102 3.5.2 Covariance Matrix Method 105 3.5.3 Resolving 180° Ambiguity 106 3.6 Data Rotation 107 3.7 Subsurface Velocity Model 108 3.7.1 1-D Layered Model Using Sonic Logs 110 3.7.2 1-D Velocity Model Calibration 112 3.8 Hypocenter Locations 118 3.8.1 Traveltime-Based Method 119 3.8.2 Waveform Based Techniques 128 3.9 Magnitude Estimation 131 3.10 Key Points 133 References 135 4 Additional Topics in Microseismic Data Processing 143 4.1 Receiver Orientation for a Deviated Well 144 4.2 I-D Velocity Model Calibration for a VTI Medium 146 4.3 Simultaneous Inversion for Velocity and Hypocenter Locations 153 4.4 Relative Hypocenter Location 156 4.4.1 Master-Event Method 157 4.4.2 Double-Difference Method 158 4.5 Moment Tensor Inversion 161 4.6 Uncertainty Analysis 166 4.7 Key Points 169 References 169 5 Microseismic Data Interpretation 173 5.1 Microseismic 173 5.1.1 Fracture Geometry and Complexity from the Hypocenter Locations 173 5.1.2 Source Parameters 175 5.1.3 Moment Tensor Analysis 176 5.1.4 S/P Amplitude Ratio 181 5.1.5 Magnitude-Distance Plot 182 5.1.6 b-value Analysis 184 5.1.7 D-value Analysis 187 5.2 Integrated Interpretation 188 5.2.1 3-D Surface Seismic 188 5.2.2 Well Logs 192 5.2.3 Engineering Data 193 5.3 Key Points 193 References 194 Appendix 200 A.1 3-D Waveform Modeling 200 A.2 Source Description 203 A.3 Ray Tracing and Traveltimes 207 References 211 Index 213 Front Matter ....Pages i-xxv Introduction (Jubran Akram)....Pages 1-19 Survey Design and Microseismic Data Acquisition (Jubran Akram)....Pages 21-53 Microseismic Data Processing (Jubran Akram)....Pages 55-122 Additional Topics in Microseismic Data Processing (Jubran Akram)....Pages 123-152 Microseismic Data Interpretation (Jubran Akram)....Pages 153-179 Back Matter ....Pages 181-196