Learning earthquake ground motions via conditional generative modeling
Pu Ren,
Rie Nakata,
Maxime Lacour,
Ilan Naiman,
Nori Nakata,
Jialin Song,
Zhengfa Bi,
Osman Asif Malik,
Dmitriy Morozov,
Omri Azencot,
N. Benjamin Erichson,
Michael Mahoney.
| Nat Comm: |
Nature Communications, vol. 17, no. 4021, 2026. |
| arXiv: |
arXiv:2407.15089, 2024. |
Abstract
Predicting high-fidelity ground motions for future earthquakes is crucial for seismic hazard assessment and infrastructure resilience. Conventional empirical simulations suffer from sparse sensor distribution and geographically localized earthquake locations, while physics-based methods are computationally intensive and require accurate representations of Earth structures and earthquake sources. We propose an artificial intelligence (AI) spectrogram generator, Conditional Generative Modeling for Ground Motion (CGM-GM). CGM-GM leverages earthquake magnitudes and geographic coordinates of earthquakes and sensors as inputs, when postprocessed with phase information, capturing spatially continuous Fourier amplitude spectra (FAS) as well as properties such as P and S arrivals, and waveform durations, without explicit physics constraints. This is achieved through a probabilistic autoencoder that extracts latent distributions in the time-frequency domain and variational sequential models for prior and posterior distributions. We evaluate the performance of CGM-GM using small-magnitude earthquake records from the San Francisco Bay Area, a region with high seismic risks. Here, we report that CGM-GM demonstrates potential for complementing physics-based simulations and non-ergodic empirical ground motion models, as well as shows promise in seismology and beyond.