Post-Seismic Deformation Following Deep Earthquakes
- Date & Time
- Online-only seminar via Microsoft Teams
Observations of surface deformation caused by earthquakes provide insights into earthquake mechanisms and rheological structure. So far, geodetic observations have been mostly limited to shallow earthquakes since the amplitude of surface deformation from deep events is considered relatively small. In this talk, I will show the detections of post-seismic signals from deep earthquakes, which open up new opportunities of understanding mantle viscosity and deep rupture processes. We examine the GPS data of one of the largest deep earthquakes ever recorded, 2018 Mw 8.2 Fiji earthquake which occurred at ~600-km depth. Taking advantage of data processing techniques such as independent component analyses, we detect a large scale post-seismic deformation that has been taking place for more than one and half years. I will discuss what we can learn about the viscosity structure and the existence of afterslip from the overall directionality and amplitude of the post-seismic deformation.