《Rupture Propagation along Stepovers of Strike-Slip Faults: Effects of Initial Stress and Fault Geometry》

• 以往认为阶跃距离临界距离为5km,但是有很多例外。
• 本文主要探索应力对于模型的影响。a long-term fault stress model: simulate steady-state stress perturbation around stepovers.
• 这样的应力扰动可以对应更长的阶跃距离。
• 15km for a releasing stepover; 7km for a restraining stepover.
• 这种应力的影响在重叠的阶跃断层中更强。
• 该文列举了很多阶跃断层的地震：1992 Mw 7.3 Landers, California, earthquake; the 2001 Mw 7.8 Kokoxili, China, earthquake; the 2016 Mw 6.5 Norcia, Italy, earthquake; the 2016 Mw 7.8 Kaikōura, New Zealand, earthquake (step gaps as large as 15-20km).
• 图1：阶跃子断层长度分别为28km，重叠为5km.用α角度标记阶跃断层重叠还是分离，<90° overlapping，>90° underlapping.
• 静摩擦力系数下降之后，屈服强度下降。20km for a releasing stepover; 9km for a restraining stepover.
• Rupture propagation across stepovers on strike-slip faults has been extensively studied through field investigation and numerical modeling. Statistics on limited surficial fault traces suggested that stepovers more than ∼5km wide would stop the propagation of fault rupture (Wesnousky, 2006)。通过实地调查和数值模拟，对走滑断层台阶上的破裂传播进行了广泛的研究。对有限地表断层痕迹的统计表明，超过5公里宽的台阶将阻止断层破裂的传播(Wesnousky, 2006)。