报告题目：Rupture dynamics of fast and slow earthquakes on long faults
报告内容简介
Among the most damaging natural hazards, earthquakes are still today one of the least understood phenomena in Earth Sciences. Earthquakes happen when rocks on either side of a tectonic fault slide. The “rupture speed” describes the spreading speed of the sliding from the hypocenter over the entire fault. The rupture speeds on long faults could beas fast asrockets (e.g., supershear earthquakes), whereas on some other faults they could be as slow as snails (e.g., slow slip events), yet a fundamental model unifying those fast and slow ruptures is still lacking. In the talk, I will present numerical simulations that show that the rupture propagation of both fast andslow earthquakes on long faults can be predicted by a newfundamental three-dimensional theory of dynamic fracture mechanics. The complete spectrum of rupture speeds is quantitatively controlled by the ratio of fracture energy to energy release rate, which depends on the frictional behaviour of the fault. In addition, I will discussthe implications of this new theory on the evaluation of futureearthquakesizes, the transition between slow and fast earthquakes, and the debates of the moment-duration scaling relations for slow earthquakes.
