14 th International Conference on Fracture (ICF14) MEGATHRUST DYNAMICS SYMPOSIUM

Transcription

1 14 th International Conference on Fracture (ICF14) MEGATHRUST DYNAMICS SYMPOSIUM Rhodes Rhodes Island, Greece June 2017 Image credit: Masuti et al. (2016) This Symposium gathers experts in various aspects of faulting and earthquake mechanics to discuss diverse topics related to megathrust dynamics. The focus will be on observational and theoretical earthquake physics, including rheology, friction, the strength of the lithosphere, and more focused subjects related to tectonic geodesy, structural geology, seismology, and physical modeling of deformation. Symposium Convener and Organiser: Dr Sylvain Barbot Assistant Professor Earth Observatory of Singapore Supported by:

2 Dear Friends and Colleagues, This is my pleasure to welcome you to the Megathrust Dynamics Symposium, a special symposium organized under the auspices of the 14th International Conference on Fracture (ICF14). The physics of earthquakes and tectonics encompasses a broad spectrum of processes across a wide range of spatial and temporal scales. Nowhere else are these forces combined with more grandeur than at subduction zones, where enormous slabs are recycled to the mantle, contributing to plate tectonics, arc volcanism, and incredible landscapes. Fault dynamics is a fascinating object of study, and our progress in this field contribute to better mitigating seismic and tsunami hazards and even perhaps, saving lives. I am very thankful for your presence today, as you all come from faraway places. All of you bring a unique perspective to the subject, and I hope our interactions in the majestic Rhodes, Greece will be inspiring and will help bridge gaps between disciplines. I look forward to discovering your latest thoughts and results. I am thankful to Emmanuel Gdoutos, ICF14 Executive Chairman and ICF Senior Vice-President-Designate , for his kind invitation to join the Scientific Advisory Board of ICF14 and thereby allowing me to organize this symposium. I am also thankful to Maybel D Silva for her support during the preparation of this event. I hope you enjoy the meeting and your stay in Rhodes. Best wishes, Dr Sylvain Barbot Symposium Convener and Organiser Megathrust Dynamics Symposium 14th International Conference on Fracture (ICF14)

3 Programme - Day 1 Monday, 19 June 2017 NAME TITLE TIME Lessons from the 2015 Mw 7.8 Gorkha, Nepal Earthquake Wei Shengji / Wang Xin Source Model and Broadband Ground Shaking Simulation of the 2015 Gorkha (Nepal) Earthquake Sequence COFFEE BREAK James Daniel Paul Moore Postseismic Deformation following the 2015 Mw 7.8 Gorkha Earthquake and the Distribution of Brittle and Ductile Crustal Processes beneath Nepal Jiuxun Yin Integration of Observational and Numerical Methods to Study the 2015 Nepal and Chile Large Earthquakes Sharadha Sathiakumar Study of Earthquake Cycles in Nepal across Geological Time Scales Using Subsurface Structural Features LUNCH Reconciling Long-Term and Short-Term Tectonics John Loveless Spatiotemporal Variation in Subduction Zone Earthquake Cycle Processes on Geodetic and Geologic Time Scales Ylona van Dinther Modeling Megathrust Dynamics across the Scales COFFEE BREAK Elizabeth Madden The Role of Splay Faults in Seafloor Deformation and Tsunami Generation during the M Sumatra-Andaman Earthquake Bunichiro Shibazaki Modeling Slow Slip Events and their Interaction with Large Earthquakes along Various Subduction Zones END OF SESSION Page 1

4 Programme - Day 2 Tuesday, 20 June 2017 NAME TITLE TIME Transient Deformation, Localized and Distributed Sylvain Barbot Earthquake Cycles with Distributed Plastic Deformation Christophe Vigny What Do We Learn from Visco-Elastic Relaxation Following the 3 Largest Megathrust Earthquakes of the 21st century COFFEE BREAK Jun Muto Heterogeneous Rheology Controlled Postseismic Deformation of the 2011 Tohoku-Oki Earthquake Sagar Masuti Estimation of the Rheological Properties of the Indian Ocean Asthenosphere Using Geodetic Data Emilie Klein Impact of Visco-Elastic Relaxation Following the 2010 Maule Earthquake in Chile on Adjacent Segments of the Subduction LUNCH Spectrum of Fault Slip Nadia Lapusta Dynamic Rupture of Creeping Fault Segments and Deeper Fault Extensions Deepa Mele Veedu A Revised Model of the Period-Doubling Parkfield Tremors COFFEE BREAK From Local to Regional Scale Subduction Dynamics Abhijit Ghosh Takane Hori Slow Earthquakes - A Major Player in the Plate Boundary Fault Dynamics A Proposal of Monitoring and Forecasting System for Crustal Activity in and around Japan using A Large-Scale High-Fidelity Finite Element Simulation Codes END OF SESSION Page 2

5 Wei Shengji Assistant Professor, Asian School of the Environment and Earth Observatory of Singapore, Wei Shengji studied earthquake sources with seismic waveform and other geodetic observations, including InSAR and GPS, as a graduate student at University of Science and Technology of China. His career began with a post doctorate at the Seismological Laboratory of California s Institute of Technology, where he expanded his research interests to include strong ground motion simulation of large earthquakes and high-frequency waveform modeling. As a faculty member at the Asian School of Environment and a Principal Investigator at the Earth Observatory of Singapore, an autonomous institute of, his current studies are focused on real-time seismology, large earthquake finite fault modeling, waveform modeling of earthquakes and velocity structures, and unveiling their relations with earthquake physics and tectonics. Wang Xin Research Fellow, Earth Observatory of Singapore, Wang Xin obtained his PhD in geophysics from the Institute of Geology and Geophysics, Chinese Academy of Sciences in He then joined the Earth Observatory of Singapore as a research fellow in seismology. His research interests focus on understanding the upper mantle discontinuity and velocity anomalous of subduction zone structure, as well as earthquakes source properties, in particular, those associated with the subduction zones. James Daniel Paul Moore Research Fellow, Earth Observatory of Singapore, I am a Research Fellow at the Earth Observatory of Singapore working in the Earthquake Physics group investigating Lithosphere Dynamics across multiple timescales. Prior to my current position I was a postdoctoral researcher in the Marine Geophysics group at Oxford and completed my DPhil as a member of the COMET research group in Oxford. My research interests include viscoelastic relaxation of the crust under loading, earthquake cycle processes, and deformation driven by volcanic systems. I examine these systems using a combination of analytic and numerical methods. My current research areas include the effect of non-linear deformation mechanisms on the earthquake cycle, with rate and state friction and off fault non-linear ductile deformation, imaging material properties of the mantle and ductile regions of the lower crust, regional compensation in dynamic topography, and nascent rifting. Jiuxun Yin PhD Student, Harvard University The studies on the source process are of great scientific value to better understand the mechanism of earthquakes. My present research focuses on the energy of earthquakes such as the propagation, energy partitioning, directivity etc. With the help of the tremendous progress of global networks and seismic arrays, we are trying to develop a spectral domain method to determine the spatial-temporal distribution of the radiated energy (absolute values) using seismogram recorded by distance/azimuthvarying stations. These results will provide very important observational constraints on the source process of earthquakes. I am also very interested in the rupture dynamics as well as subduction zones. Page 3

6 Sharadha Sathiakumar PhD Student, Asian School of Environment, Sharadha Sathiakumar is a first year PhD student in ASE. Her interests include earthquake cycle modelling and fault bend fold dynamics. Before starting her PhD she was a Research Associate at EOS with expertise in developing seafloor geodesy capabilities for a marine robot. John Loveless Assistant Professor, Geosciences, Smith College Jack Loveless received his undergraduate degree from the University of New Hampshire in 2002 and PhD. from Cornell University in He completed a post-doctoral fellowship at Harvard University before starting a faculty position at Smith College in Ylona van Dinther Senior Scientist and Lecturer, Swiss Federal Institute of Technology (ETH), Zurich Ylona van Dinther studied Geophysics at Utrecht University. She received her PhD on bridging scales from geodynamics towards the seismic cycle from ETH Zurich, while working at the Swiss Seismological Service. For her post doc she joined the new Computational Seismology group at ETH, where she now as a Senior Scientist and Lecturer leads the subgroup of Earthquake Physics in which 6 PhD students are involved. She is currently applying data assimilation techniques to seismic cycles and is interested in building a comprehensive forward and inverse modeling framework to improve our physical understanding of the spatiotemporal occurrence of earthquakes. Elizabeth Madden (Betsy) Post-Doctoral Researcher, Ludwig-Maximilians-Universität München Elizabeth Madden received her PhD from Stanford University in 2013, where she studied the effects of 3D fault geometry on earthquake mechanics with a focus on the 1992 Landers, CA earthquake. Her postdoctoral research at the University of Massachusetts-Amherst focused on the energy budgets of growing faults and the development of a 2D fault propagation code, GROW. She is currently a post-doctoral fellow with the ASCETE Project at Ludwig-Maximilian University in Munich, Germany, studying the effects of subduction zone geology and fault geometry on megathrust earthquake dynamics and tsunami generation. Page 4

7 Bunichiro Shibazaki Chief Research Seismologist, Building Research Institute, Japan Bunichiro Shibazaki s main research topics are modeling earthquake generation processes, slow slip events along various subduction zones, and deformation processes of the island arc lithosphere. He received a BA from the University of Tokyo in 1988 and received a PhD in science from the University of Tokyo in From 1993 to 1995, he studied at the National Research Institute for Earth Science and Disaster Prevention. He has worked at the Building Research Institute since Sylvain Barbot Assistant Professor, Asian School of the Environment and Earth Observatory of Singapore, Sylvain Barbot studied earthquake physics and geodesy at the Institut de Physique du Globe de Paris, France, and at the Institute of Geophysics and Planetary Physics at the Scripps Institution of Oceanography. As a graduate, his research focused on transient lithospheric deformation following earthquakes on strike-slip faults. During his post doctorate at the California Institute of Technology, he studied the dynamics of earthquake cycles using rate-and-state friction. Today, as a faculty member at the Earth Observatory of Singapore, his research focus is to understand the physics of crustal and lithosphere dynamics across many temporal and spatial scales. His main interests are to understand the role of geometry and chemistry, and the distribution of on-fault and off-fault deformation in the generation of earthquakes. Christophe Vigny Professor, Directeur du Laboratoire de Géologie, École Normale Supérieure, Paris I use modern style space geodesy (GPS): I install networks of geodetic benchmarks which I survey regularly to monitor their positions and arrays of permanent cgps stations. These measurements allow us to quantify the crustal deformation before, during, and after an earthquake. My goal is to understand how tectonic plates move and deform, how major earthquakes nucleate and rupture. I apply these methods on different faults around the world where seismic hazard is high: South-East Asia (Indonesia Sumatra and Sulawesi, Malaysia, Thailand, Myanmar), Chile (from Patagonia to Atacama), Iran (Zagros, Alborz), Nepal (Himalayas), Djibouti (East African Rift), etc. Jun Muto Assistant Professor, Department of Earth Science, Tohoku University Jun Muto studied structural geology at Tohoku University. He received his PhD on field survey and microstructural analysis of deformed crustal rocks from Tohoku University. For his post doc, he joined the Tectonophycs group at Brown university with the collaboration to Jan Tullis and Greg Hirth and have conducted deformation experiments of crustal rocks such as quartz and feldspars with special emphasis on the role of fluids. He is currently working on the numerical modeling of post-seismic deformation of the 2011 Tohokuoki earthquake as well as laboratory deformation experiments of lower crustal and upper mantle rocks to improve our understanding rheological properties of dynamic earth. Page 5

8 Sagar Masuti PhD Student, Asian School of the Environment, I am a 3rd year PhD student at Nanyang Technological University studying postseismic data to infer the rheology of the oceanic asthenosphere. In particular, I am interested in the transient rheology of olivine (the most abundant mantle mineral). With the help from my advisor (Asst Prof Sylvain Barbot), I have collaborated with experimental scientists (Prof Shun-ichiro Karato) to quantify the transient rheology of olivine. Nadia Lapusta Professor, Mechanical Engineering and Geophysics, California Institute of Technology Emilie Klein Postdoctoral Scholar, Institute de Physique du Globe de Strasbourg, France Emilie Klein is currently a Postdoctoral fellow at the Institut Physique du Globe de Strasbourg. She obtained her Ph.D from the Laboratoire de Géologie of the Ecole Normale Supérieure in Paris in She will integrate in early July the Institute of Geophysics and Planetary Physics at the University of California, San Diego, as a Postdoctoral Scholar funded from a NASA federal grant. Her main research interests focus on the crustal deformation associated with the seismic cycle in subduction zones but also along transform faults. She carried out her Ph.D. on the modeling of postseismic deformation following the Maule earthquake (Mw8.8 in Chile, 2010), using GPS observations and Finite Element Models (under the supervision of C.Vigny and L. Fleitout). Her postdoctoral research is currently focused on the interseismic deformation along the North Anatolian Fault, aiming at characterizing the strain accumulation along the Marmara fault through a probabilistic bayesian approach. In the meantime, she continues working on the seismic cycle along the Chilean subduction zone, particularly after the occurrence of the 2015 Illapel earthquake. My research is directed towards a better understanding of friction and fracture phenomena on both fundamental and practical levels through analytical and numerical modeling. From the fundamental point of view, processes of fracture and friction are fascinating, nonlinear, and often dynamic, phenomena occurring on many scales. In practice, understanding friction and fracture is of vital importance to many industrial and defense applications. My special interest is in mechanics and physics of earthquakes and aseismic slip, where frictional faulting and cracking are key ingredients. Page 6

9 Deepa Mele Veedu PhD Student, Asian School of the Environment, Deepa Mele Veedu is a 3rd year Ph.D. student at the Earth Observatory of Singapore. She holds a Masters degree in Marine Geophysics from the Cochin University of Science & Technology and a Masters degree in Exploration Geosciences from the Indian Institute of Technology, Kharagpur. She is interested in the diversity of earthquake rupture styles, particularly slow ruptures preceding fast ruptures. She has used the phenomenon of slow and fast ruptures on a single fault patch to explain the mechanism behind the period-doubling tremors on the San Andreas Fault as a special case. Currently, she works on a universal model to explain the fundamental basis for a range of earthquake observations. Abhijit Ghosh Assistant Professor, University of California, Riverside Abhijit Ghosh is an earthquake seismologist. The broad goal of his research is to better understand the physics of earthquakes, the processes that control them, and their associated hazards by examining a wide spectrum of fault slip across a broad range of spatial and temporal scales. He has pioneered work on slow earthquakes a relatively new branch of earthquake science using innovative array techniques. He earned his Bachelor s Degree in Geology from the University of Calcutta, Kolkata, India, and PhD in Geophysics in 2011 from the University of Washington, Seattle, USA. Before joining the University of California, Riverside, as an Assistant Professor, he received a Postdoctoral Fellowship awarded by the National Science Foundation, USA. Takane Hori Senior Scientist, Center for Earthquake and Tsunami, Japan Agency for Marine-Earth Science and Technology Takane Hori is a Senior Scientist at JAMSTEC (Japan Agency for Marine- Earth Science and Technology) and the leader of Earthquake and Tsunami Forecasting System Research Group in R&D Center for Earthquake and Tsunami. He obtained his Dr.(Sci.) at the Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University in After graduation, he stayed there for a year as a JSPS Post- Doc. He then moved to JAMSTEC in For further information regarding the Symposium please contact: Maybel D silva Earth Observatory of Singapore maybel_dsilva@ntu.edu.sg Design credit: Yvonne Soon, Community Engagement Office, Earth Observatory of Singapore Page 7