State-of-the-Art Review and Analysis in Earthquake Forecasting Master Thesis Handed in by: Dipl.-Ing. Andreas Maximilian Schäfer Ludwig-Maximilians Universität München Department of Earth and Environmental Science Institute of Geophysics Supervised by: Prof. Dr. Hans-Peter Bunge & Prof. Dr. Heiner Igel Advised by: Dr. James Daniell & Dr. Matthias Hackl February 2014 1 Introduction 2 Andreas Schäfer Table of Contents Table of Contents 1 Introduction ....................................................................................................... 1 1.1 Abstract ........................................................................................................ 1 1.2 Introduction and Overview ............................................................................ 1 1.3 Scientific Objectives ..................................................................................... 2 2 Theory ................................................................................................................ 4 2.1 Plate Tectonics ............................................................................................. 4 2.1.1 Plate Movement and Interactions ............................................................ 4 2.1.2 Subduction Zones ................................................................................... 6 2.2 Earthquakes ................................................................................................. 7 2.2.1 Focal Mechanisms .................................................................................. 7 2.2.2 Magnitude Types & Source Parameters ................................................. 9 2.2.3 Earthquake Statistics ............................................................................ 11 2.3 Probabilistic Seismic Hazard Analysis ........................................................ 12 2.3.1 Probabilistic Seismic Hazard Methodology ........................................... 13 2.3.2 Seismic Forecasting .............................................................................. 13 2.3.3 Seismic Zonation .................................................................................. 14 3 Review ...............................................................................................................16 3.1 Overview of Methods .................................................................................. 16 3.2 Related Projects ......................................................................................... 17 3.3 Survey Parameters ..................................................................................... 18 3.4 Time-independent Methods ........................................................................ 19 3.4.1 Relative Intensity (RI) ............................................................................ 19 3.4.2 Earthquake Prediction in California (EPiC) ........................................... 19 3.4.3 Asperity Likelihood Model (ALM) .......................................................... 20 3.4.4 HAZGRIDX ........................................................................................... 20 3.4.5 Adaptively Smoothed Seismicity (ASS) ................................................ 21 3.4.6 PEGASOS EG1b approach .................................................................. 21 3.4.7 Simple Smoothed Seismicity (Triple-S) ................................................. 22 3.5 Time-dependent Methods .......................................................................... 22 3.5.1 Pattern Information (PI) ......................................................................... 22 3.5.2 Reverse Tracing of Precursors (RTP) ................................................... 23 3.5.3 Epidemic-type Aftershock Sequence (ETAS)........................................ 23 3.5.4 Every Earthquake a Precursor According to Scale (EEPAS) ................ 24 3.5.5 Epidemic Rate-Strain (ERS) ................................................................. 24 3.5.6 Short-term Aftershock Probabilities (StAP) ........................................... 25 Andreas Schäfer i Table of Contents 3.5.7 Early Aftershock Statistics (EAST) ........................................................ 25 3.6 Hybrid Methods .......................................................................................... 26 3.6.1 Fault Slip and Smoothed Seismicity (FSSS) ......................................... 26 3.6.2 Hybrid Seismicity Method (HSM) .......................................................... 26 3.6.3 Long-term Stress Transfer (LtST) ......................................................... 27 3.6.4 Seismic Hazard Inferred from Tectonics (SHIFT) ................................. 27 3.6.5 Fault-oriented Earthquake Forecast (FoEF) ......................................... 28 3.7 Static triggering .......................................................................................... 29 3.7.1 Overview ............................................................................................... 29 3.7.2 Theory ................................................................................................... 30 3.8 Catalogue Development ............................................................................. 32 3.8.1 Catalogue content ................................................................................. 32 4 Reconstruction .................................................................................................33 4.1 Time-independent Method Toolbox ............................................................ 33 4.1.1 Declustering .......................................................................................... 34 4.1.2 Smoothing ............................................................................................. 36 4.1.3 Gutenberg-Richter Handling ................................................................. 40 4.2 Time-dependent Method reconstruction ..................................................... 42 4.2.1 Pattern Informatics ................................................................................ 43 4.2.2 Epidemic-Type of Aftershock Sequences ............................................. 45 4.3 Fault-oriented time-(in-)dependent b-value ................................................ 49 4.4 Overview and Summary of Coding ............................................................. 51 5 Testing...............................................................................................................53 5.1 Testing Algorithms ...................................................................................... 53 5.1.1 N-Test ................................................................................................... 54 5.1.2 S-Test & M-Test .................................................................................... 54 5.2 The Testing Range ..................................................................................... 56 5.2.1 Data ...................................................................................................... 56 5.3 Test Results – time-independent ................................................................ 59 5.3.1 Methods & Application on Testing Range ............................................. 59 5.3.2 Results .................................................................................................. 60 5.4 Test Results – time-dependent .................................................................. 66 5.4.1 Test Results – Pattern Informatics ........................................................ 66 5.4.2 Test Results – Time-dependent b-value ............................................... 69 5.4.3 Test Results – Epidemic Type of Aftershock Sequences ...................... 71 5.5 Test Conclusion.......................................................................................... 75 6 Hybrid Method Development ...........................................................................77 6.1 Idea ............................................................................................................ 77 6.2 Theory ........................................................................................................ 78 6.2.1 Data ...................................................................................................... 79 6.2.2 Slip accumulation and release .............................................................. 80 ii Andreas Schäfer Table of Contents 6.3 The Slip Accumulation Method (SAM) ........................................................ 81 6.3.1 Method description ................................................................................ 81 6.3.2 Calibration ............................................................................................. 84 6.4 Results ....................................................................................................... 85 7 Case Studies .....................................................................................................89 7.1 Time-independent Forecast ....................................................................... 89 7.2 Time-dependent Forecast .......................................................................... 90 7.3 Summarized Forecast ................................................................................ 91 8 Conclusion ........................................................................................................93 8.1 A brief Summary of Earthquake