Dynamic fracturing by successive coseismic loadings leads to pulverization in active fault zones

摘要: Previous studies show that pulverized rocks observed along large faults can be created by single high-strain rate loadings in the laboratory, provided strain is higher than a certain pulverization threshold. Such are analogous to seismic events. In reality, have been subject numerous events rather one event. Therefore, effect of successive “milder” on threshold investigated applying loading conditions below initial Single and experiments were performed quartz-monzonite using Split Hopkinson Pressure Bar apparatus. Damage-dependent petrophysical properties elastic moduli monitored incremental strains. Furthermore, it shown reduced dynamic from rates ~180 s−1 ~90 s−1. To do so, imperative rock experiences fracturing during prior pulverization. Combined with an earthquake rupture event, following generalized fault damage zone structure perpendicular will develop: furthest plane, there stationary outer boundary bounds dynamically fractured rocks. Closer fault, delimits band rock. Consecutive cause progressive broadening rocks, eventually creating wider mature faults.