Inelastic off-fault deformation can lead to large tsunamigenesis in different tectonic settings. Here a mechanism for tsunami generation by strike-slip earthquakes that involves dynamic off-fault failure at restraining bends is presented. Dynamic rupture on a vertical strike-slip fault is modeled with undrained inelastic off-fault response incorporated by the Drucker-Prager yield criterion. I show that in a local transpressive stress regime dynamic off-fault failure at restraining bends produces significantly larger and more localized surface uplift than is produced by purely elastic dislocation models, resulting in a positive flower and coseismic pop-up structure. The larger uplift is due to frictional sliding with a thrust component on conjugate microfractures, modeled by inelastic deformation. The short-wavelength inelastic uplift, largely controlled by bend size, is shown to generate localized tsunami efficiently in a shallow bay by fully coupling dynamic rupture, ocean acoustic waves, and tsunami. Fully-coupled models also indicate that supershear rupture on a vertical planar strike-slip fault does not generate large tsunami as the large kinetic energy of supershear rupture is carried away by ocean acoustic waves. Dynamic off-fault failure at fault complexities, such as restraining bends and compressional stepovers, may need be urgently incorporated in the current tsunami hazard assessments in strike-slip environments.

中文翻译：

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走滑抑制弯曲处的动态断层破坏和海啸发生：浅湾动态破裂、海洋声波和海啸的全耦合模型

非弹性断层变形可能导致不同构造环境下的大规模海啸发生。这里提出了一种由走滑地震引发海啸的机制，其中涉及限制弯曲处的动态断层破坏。垂直走滑断层上的动态破裂采用德鲁克-普拉格屈服准则中包含的不排水非弹性断层响应进行建模。我表明，在局部压应力状态下，约束弯曲处的动态断层破坏会产生比纯弹性位错模型产生的更大且更局部的表面隆起，从而产生正花和同震弹出结构。较大的隆起是由于共轭微裂缝上带有推力分量的摩擦滑动所致，通过非弹性变形建模。短波长非弹性隆起主要由弯曲尺寸控制，通过完全耦合动态破裂、海洋声波和海啸，可以在浅海湾有效地产生局部海啸。全耦合模型还表明，垂直平面走滑断层上的超剪切破裂不会产生大海啸，因为超剪切破裂的大量动能被海洋声波带走。断层复杂性下的动态断层破坏，例如限制弯曲和压缩步距，可能需要紧急纳入当前走滑环境中的海啸灾害评估中。