New rupture theory challenges classical earthquake propagation model, allowing continuous propagation through previously 'forbidden' speed range
Researchers have developed a new rupture theory that allows earthquakes to propagate continuously through the super-Rayleigh speed range, contradicting classical theory which deemed this range 'forbidden.' The new model incorporates friction that depends on slip rate, a property observed in laboratory experiments. This finding could improve understanding of fast earthquake propagation and the mechanisms driving the most damaging seismic events.
A new theoretical framework challenges the classical rupture theory that has long predicted earthquakes cannot propagate in the super-Rayleigh regime—the speed range between Rayleigh and shear wave-speeds. The revised theory incorporates rate-dependent friction, a property commonly observed in experimental studies, and shows that earthquakes can continuously propagate through this previously forbidden range into the super-shear regime without an abrupt transition. The model's predictions agree quantitatively with numerical simulations up to the Rayleigh wave-speed and explain how frictional rate nonlinearity enables smooth passage through the super-Rayleigh range. These results suggest that accounting for realistic friction properties fundamentally changes predictions about fast earthquake propagation, with potential implications for understanding the most severe seismic events.
What's missing
The study's own limitations and open questions are not detailed in the abstract provided. Specifically, the abstract does not discuss: the range of slip rates or fault conditions under which the rate-dependent friction model applies; whether the theory has been validated against real earthquake data or only numerical simulations; the practical implications for earthquake prediction or hazard assessment; or remaining uncertainties in the model.
What different sources said
- arXiv physicsCenter
Breakdown of the classical rupture theory and earthquake propagation in the "forbidden" super-Rayleigh range
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