NH014-0016
Coupled dynamic earthquake rupture-tsunami modeling for the Hellenic Arc - towards physics-based tsunami hazard assessment in the Eastern Mediterranean Sea
Wednesday, 9 December 2020
Poster
Sara Aniko Wirp1, Alice-Agnes Gabriel2, Lukas Krenz3, Stefano Lorito4, Jacopo Selva4, Fabrizio Romano4, Roberto Basili5, Michael Bader3 and Eric M Dunham6, (1)Ludwig Maximilians University of Munich, Earth and Environmental Sciences, Munich, Germany, (2)Ludwig Maximilians University of Munich, Munich, Germany, (3)Technical University of Munich (TUM), Department of Informatics, Munich, Germany, (4)INGV National Institute of Geophysics and Volcanology, Rome, Italy, (5)Istituto Nazionale Geofisica e Vulcanologia, Rome, Italy, (6)Stanford University, Department of Geophysics, Stanford, CA, United States
Abstract:
The Hellenic Arc is an active seismotectonic zone (Papadopoulos et al., 2010) sourcing several destructive tsunamis devastating the Mediterranean coasts in the past (Gailler et al., 2016). For tsunami early warning and hazard assessment, data-driven kinematic models of fault slip are often translated into static seafloor displacement (Okada, 1985). However, in these models the slip distribution is often highly non-unique (Mai et al., 2016) and time-dependent effects are neglected. Dynamic rupture models can provide physically consistent and time dependent slip distribution across complex fault networks. The resulting seafloor displacement can then be used to source tsunamis highlighting complex earthquake-tsunami interaction (Ulrich et al., 2019, Amlani et al., 2020). Previous tsunami models sourced by 3D dynamic rupture models typically link to the shallow water equations to simulate the ocean waves. Fully coupled approaches model earthquakes, acoustic waves and tsunamis simultaneously by accounting for compressibility, gravity and elasticity (Lotto and Dunham, 2018; Lotto et al., 2017). Recently, this coupling approach was successfully implemented in SeisSol (www.seissol.org), a flagship code of the ChEESE project (www.cheese-coe.eu).
In this study, we use SeisSol to model a range of 3D dynamic rupture subduction earthquake scenarios on the Hellenic Arc and the coupled tsunami genesis. The modeling area covers the eastern Mediterranean Sea and includes complex subduction geometry (e.g., Scala et al., 2019), bathymetry, topography and detailed subsurface geological structure. Varying hypocenter locations and magnitudes are used to study differences in tsunami generation and sea surface height at the coastal regions. We compare the 3D fully coupled approach to a two-step hydrostatic shallow water approach (sam(oa)²-flash, Madden et al., 2019) which uses the time-dependent earthquake displacements and velocities. Our results have the potential to extend probabilistic tsunami hazard assessment, e.g. in comparison to using stochastic slip distribution (e.g., NEAMTHM18, http://www.tsumaps-neam.eu/).
