A Probabilistic View on Rupture Predictability: All Earthquakes Evolve Similarly

Abstract

Ruptures of the largest earthquakes can last between a few seconds and several minutes. An early assessment of the final earthquake size is essential for early warning systems. However, it is still unclear when in the rupture history this final size can be predicted. Here we introduce a probabilistic view of rupture evolution ‐ how likely is the event to become large ‐ allowing for a clear and well‐founded answer with implications for earthquake physics and early warning. We apply our approach to real time magnitude estimation based on either moment rate functions or broadband teleseismic P arrivals. In both cases, we find strong and principled evidence against early rupture predictability because differentiation between differently sized ruptures only occurs once half of the rupture has been observed. Even then, it is impossible to foresee future asperities. Our results hint toward a universal initiation behavior for small and large ruptures.

Smartphones enabled up to 58 seconds strong-shaking warning in the M7.8 Türkiye earthquake

“…This predictability of earthquake magnitude using records of the early phase of the earthquake is consistent with seismological studies that reveal that the early phase of strong earthquakes recorded at close and regional distances is more energetic than that of weak earthquakes (Colombelli et al, 2020) or with geological analysis that reveals that hypocentres are often close to regions of large slip (Manighetti et al, 2005). However, this predictability has not been confirmed by a few recent studies (Münchmeyer et al, 2022) using teleseismic records, which may indicate the important role of nearby/regional records (to which smartphone data contribute) for predictability.…”

Machine Learning in Earthquake Seismology

“…Neural networks can be used to study eventual rupture predictability and magnitude of large events based on the initial stages of rupture in a probabilistic framework (Münchmeyer et al 2022a). Their results suggested universal initiation behavior for small and large ruptures.…”