HighFEM

Earthquakes are among the most devastating natural hazards humanity is confronted with. Earthquake shaking spans a very wide range of frequencies, with classic sensors designed to record signals over four orders of magnitude in frequency. The low frequency part of seismic signals is readily used to study earthquake processes and the interior structure of the Earth. Using the high frequency parts of earthquake wavefields, on the other hand, is more challenging, because i) high frequency signals are hard to observe: seismometers are usually too far away and too sparse to record high frequency wavefields with the necessary resolution; ii) high frequency wavefields are hard to model: the computational cost of wavefield simulations grows with the 4th power of frequency, and we lack the detailed knowledge of underground geological structures that affect and modify the signals at this small scales. Next level underground laboratories, such as ETHZ’s Bedretto Lab or Utah Forge, however, strongly reduce the observational limitations, in that they facilitate earthquake monitoring from unusually close distances, and with high sensor densities. Here we propose to use this opportunity, and to jointly leverage high performance computing, generative deep modeling and the massive, near-field earthquake data sets that the novel laboratories provide, to model and study earthquake waveforms up to very high frequencies. We will use these modelling capabilities to achieve a range of science goals, including improved seismicity monitoring algorithms, and to study small scale earthquake source processes and ground motion site response.