Tsunami Earthquake or Attenuating Crustal Structure: Ground Motions from the May 2nd, 2020, M6.6 Ierapetra (Crete) Earthquake
Loading...
Date
2021-09-13
Authors
Chatterjee, Avigyan
Journal Title
Journal ISSN
Volume Title
Publisher
University of Oregon
Abstract
Preliminary analysis of the ground-motions from the shallow M6.6 reverse-slip earthquake that struck the island of Crete on May 2nd, 2020, 12:51 UTC, indicates low shaking for the earthquake’s magnitude. Such behavior is common to ‘Domain-A’ or tsunami earthquakes according to Lay, et.al, 2012. However, low ground motion onshore Crete, and areas on the back-arc, from such an event could also be a property of the path the earthquake signal traverses. Local shallow subduction zone structure and its high attenuation, due to the overlying thick accretionary wedge, could also explain the low ground motions. Analyzing the ground-motions and rupture properties of this earthquake will greatly help us refine our understanding of its source processes and augment our grasp over building better early warning systems. We perform a regional analysis of the ground-motions of the M6.6 2020 Ierapetra (Crete) tsunamigenic earthquake, its aftershocks, as well as historical seismicity, to understand whether the ground motions we observe are due to source, or path effects. To detangle these effects, we decompose event, path, and site residuals from ground-motion models for all earthquakes in this dataset. Finally, if found to be a “Domain A” tsunami earthquake, implementation of recent algorithms of combined near-field seismic and geodetic data could determine how well such early warning methods will perform in real-time, for this event and for other similar events.