ASCETE - Advanced Simulation of Coupled Earthquake and Tsunami Events
Funded by the Volkswagen Foundation
Earthquakes and tsunamis represent the most dangerous natural catastrophes and can cause large numbers of fatalities and severe economic loss in a single and unexpected extreme event as shown in Sumatra in 2004, Samoa in 2009, Haiti in 2010, or Japan in 2011. Both phenomena are consequences of the complex system of interactions of tectonic stress, fracture mechanics, rock friction, rupture dynamics, fault geometry, ocean bathymetry, and coast line geometry. The ASCETE project forms an interdisciplinary research consortium that – for the first time – will couple the most advanced simulation technologies for earthquake rupture dynamics and tsunami propagation to understand the fundamental conditions of tsunami generation. To our knowledge, tsunami models that consider the fully dynamic rupture process coupled to hydrodynamic models have not been investigated yet. Therefore, the proposed project is original and unique in its character, and has the potential to gain insight into the underlying physics of earthquakes capable to generate devastating tsunamis.
Objectives and Key Questions
Our main objective is to study the interaction of undersea earthquake rupture mechanisms, resulting ocean bottom displacements, and the corresponding sea level disturbance and subsequent potential tsunami generation in order to answer the core question:
“Under which conditions do undersea earthquakes generate devastating tsunamis?”
To this end, a number of key and most relevant scientific questions have to be addressed beforehand such as:
- How does the dynamic rupture propagate on a geometrically complex fault?
- How does rupture propagate on large-scale earthquakes, and what are the conditions whether rupture stops or becomes a large event?
- What subsurface conditions lead to surface-rupturing or buried earthquakes?
- What are crucial conditions of stress orientation and fault plane geometry?
- What role do shallow dip angles, splay faults, and shallow weak zones play for near-shore tsunami generation?
- Which earthquake parameters define the magnitude of the generated tsunami?
- What rupture parameters have the strongest influence on the water column?
- Is there a threshold magnitude for tsunami wave generation, and how can this be understood physically?
- How does dynamic seafloor deformation influence the tsunami behaviour at the shore?
- What is the exact effect of the interaction of a tsunami wave with complex topography or with tidal waves, with respect to the characteristic of the initial condition?
- Do the seismic waves generated by the earthquake have a major influence on the harmfulness of the generated tsunami?
Partners in the ASCETE Project are:
- Martin Käser, Ludwig-Maximilians-Universität München Dept. of Earth Sciences, Geophysics
- Jörn Behrens, KlimaCampus, Universität Hamburg, Numerical Methods in Geosciences
- Michael Bader, Technische Universität München Institut für Informatik
- Luis A. Dalguer, Swiss Seismological Service ETH-Zurich
Responsible group members
- Stefan Vater
- Jörn Behrens