Rupture Interaction with Fault Jogs
Rupture Interaction with Fault Jogs
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DOI：
10.1029/gm037p0157
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发表时间：
2013-03
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影响因子：
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通讯作者：
R. Sibson
中科院分区：
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作者：
R. Sibson
在主要的跨流断层系统中，中大型地震破裂的传播受到其大规模脆性基础设施的影响，这些基础设施包括通常约1公里宽的主断裂带内的梯级分割和主滑动面（PSS）的曲率。这些PSS不规则性被分为扩张式和反扩张式断层断层，这取决于在断层断层上面积增加或减少的趋势。高精度的微地震研究表明，在整个发震区，慢跑常常延伸到10公里左右的深度。根据地貌学的证据，更大的慢跑可能会持续100到105年。虽然反膨胀运动对短期和长期位移都构成障碍，但膨胀运动似乎是一种动能障碍，能够干扰或阻止地震破裂，但允许随时间变化的滑动转移。在反张性滑动的情况下，滑移转移是由广泛的附属断裂调节的，但对于张性滑动，它还包括位于梯队台阶上的张性裂缝开口。在流体饱和的地壳中，连接伸展断裂系统的快速打开以允许地震破裂的通过，受到与地壳宽度成比例的诱导吸力的反对。当流体压力通过扩散重新平衡时，在膨胀缓动处的破裂停止可能随后发生延迟滑移转移。与不同断层滑动相关的余震分布反映了它们内部结构和力学响应的这些差异。
Propagation of moderate to large earthquake ruptures within major transcurrent fault systems is affected by their large‐scale brittle infrastructure, comprising echelon segmentation and curvature of principal slip surfaces (PSS) within typically ∼1 km wide main fault zones. These PSS irregularities are classified into dilational and antidilational fault jogs depending on the tendency for areal increase or reduction, respectively, across the jog structures. High precision microearthquake studies show that the jogs often extend throughout the seismogenic regime to depths of around 10 km. On geomorphic evidence, the larger jogs may persist for periods >105years. While antidilational jogs form obstacles to both short‐ and long‐term displacements, dilational jogs appear to act as kinetic barriers capable of perturbing or arresting earthquake ruptures, but allowing time‐dependent slip transfer. In the case of antidilational jogs slip transfer is accommodated by widespread subsidiary faulting, but for dilational jogs it additionally involves extensional fracture opening localized in the echelon stepover. In fluid‐saturated crust, the rapid opening of linking extensional fracture systems to allow passage of earthquake ruptures is opposed by induced suctions which scale with the width of the jog. Rupture arrest at dilational jogs may then be followed by delayed slip transfer as fluid pressures reequilibrate by diffusion. Aftershock distributions associated with the different fault jogs reflect these contrasts in their internal structure and mechanical response.