International Joint Workshop on
Slow-to-Fast Earthquakes 2022
Slow-to-Fast Earthquakes 2022
Scaling slow-to-fast earthquakes with heterogeneity
Scope:
Tectonic faults exhibit a spectrum of deformation modes, ranging from grain boundary creep to plate boundary slow slip and acoustic emission to huge destructive fast earthquakes, with these processes spanning a wide range of spatial and temporal scales. Various physical mechanisms have been proposed to explain small-to-large and slow-to-fast seismo-geodetic events. Each mechanism has a different scale dependency, which is further affected by the multi-scale heterogeneity of the fault structure. However, physical modeling of micro-processes, laboratory experiments, and geological investigations of detailed elementary processes commonly consider only a small range of scales, generally limited to a few meters. For example, there is no obvious way to adapt laboratory-derived frictional and hydraulic properties to macroscopic seismic slip on heterogeneous natural faults. This plenary session will discuss the scaling of slow-to-fast earthquakes occurring on heterogeneous fault structures using observations, experiments, and modeling that employ geological, geophysical, and/or interdisciplinary approaches to better understand the physical mechanisms of slow-to-fast earthquakes.
Keynote speakers:
Daniel Faulkner (The University of Liverpool)
Satoshi Ide (The University of Tokyo)
Moderators:
Yohei Hamada, Takanori Matsuzawa, Takahiro Hatano
Diagnostic of slow-to-fast earthquakes by emerging technologies
Scope:
Data-driven technologies that incorporate machine learning and statistics have been extensively applied in the past few years to detect earthquakes from seismic waveforms more completely, discriminate between slow and fast earthquakes, and extract small fault displacements from geodetic data using well-defined optimization rules. Simultaneously, the rapid development of ultra-dense seismic observations using distributed acoustic sensing and large-N seismic arrays has enabled the tracking of seismic wavefields at a higher frequency than ever, resulting in the detection of tiny seismic events and the precise location of high-frequency seismic sources. Furthermore, new technologies that employ quantum optics and unmanned aerial vehicles have been proposed to improve the temporal resolution of slow-deformation monitoring. A coalescence of data-driven technologies and innovative observations, which has been accelerated by high-performance computing, will provide new insights into the physical mechanisms that drive slow and fast earthquakes, in turn leading to an understanding of the interactions between these slow and fast phenomena. This session will discuss the data-driven analysis of slow and fast earthquakes using emerging technologies, and improvements in the monitoring capability of seismic and geodetic phenomena.
Keynote speakers:
Bertrand Rouet-Leduc (Disaster Prevention Research Institute, Kyoto University)
Zhongwen Zhan（Caltech Seismological Laboratory）
Moderators:
Aitaro Kato, Yoshiyuki Tanaka, Satoshi Ide
Slow-to-fast earthquakes and fluid migration
Scope:
Both slow and fast slip on faults are commonly observed in a variety of tectonic environments worldwide. Geophysical and geological observations in subduction zones have suggested that fluids and the rheology of plate-boundary shear zones play important roles in the observed slip behaviors during slow-to-fast earthquakes. Specifically, a shear zone hosting slow slip is commonly assumed to be weak due to its low effective stress and high fluid pressure. This session aims to discuss the factors controlling slow-to-fast slip using data obtained from seismic and geodetic observations, geological field studies, laboratory experiments, and numerical modeling. We welcome multidisciplinary contributions that undertake comparisons of different subduction margins and other plate-boundary environments to reveal the physicochemical processes that control slow-to-fast slip, with a particular focus on fluids and the rheology of the plate interface. We also welcome contributions that reveal slow- versus fast-deformation processes in landslide and glacial environments, as these may provide important analogs that will advance our understanding of these seismogenic processes.
Keynote speakers:
Whitney M. Behr (ETH Zürich)
Cailey B. Condit (University of Washington)
Moderators:
Yoshihiro Ito, Asuka Yamaguchi, Kohtaro Ujiie