Abstract The XiLuoDu reservoir dam located on the Jinsha River is one of the largest dams in the world. Nearby faults are very active, and two M > 7 strong earthquakes have occurred around the dam. Simulating the rupture dynamics of potential earthquakes on the surrounding faults is very important to estimate the seismic hazard for the dam. In this research, we use the curved grid finite difference method (CG-FDM) to simulate spontaneous ruptures on the major faults around the dam. The main results are that the Leibo middle and south faults (LBMF and LBSF) are more likely to have large destructive earthquakes than the Mabian-Yanjin east fault (MB-YJEF). Asperities on faults that have an impact on strong ground motion are formed under the combined influence of the regional background stress field and fault geometry. Spontaneous ruptures on the LBMF and LBSF are mainly strike-slip with minor thrust components, while those on the MB-YJEF are strike-slip and thrust; these results are consistent with the focal mechanisms of recorded small and moderate earthquakes in this area.

中文翻译：

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西洛渡水库大坝周边潜在地震破裂动力学模拟

摘要 位于金沙江上的溪洛渡水库大坝是世界上最大的水坝之一。附近断层非常活跃，大坝周围发生了两次 M > 7 强地震。模拟周围断层上潜在地震的破裂动力学对于估计大坝的地震危险性非常重要。在这项研究中，我们使用曲线网格有限差分法（CG-FDM）来模拟大坝周围主要断层的自发破裂。主要结果是雷波中南断裂（LBMF和LBSF）比马边-盐津东断裂（MB-YJEF）更容易发生大破坏性地震。在区域背景应力场和断层几何形状的共同影响下，形成了对强地震动有影响的断层上的凹凸不平。LBMF和LBSF自发破裂以走滑为主，推力成分较小，MB-YJEF自发破裂为走滑和逆冲；这些结果与该地区记录的中小地震的震源机制一致。