AI 中文总结
本研究采用统一方法，通过分析三次地震的视频，结合图像跟踪技术捕捉同震地表断层位移，明确其持续时间、速度特征及时间历程复杂性，为相关研究提供新的数据来源。
AI 中文摘要
已有案例表明，闭路电视（CCTV）摄像机可捕捉到包括同震断层滑动在内的地表位移，这类视频记录能提供远离断层的地震仪所未包含的信息。本文采用统一方法，分析了2018年花莲地震、2025年曼德勒地震和2026年熊本地震三次地震的地表位移视频；为消除强地面运动和摄像机抖动的影响，所有视频帧均经过平移、缩放和旋转，使图像中的1或2个矩形参考区域保持固定；随后通过计算图像相关系数，跟踪被认为代表断层运动相关位移的矩形区域。该分析可在抑制强地面运动影响的同时，估算地表位移的时间演化，尤其是持续时间。尽管三次地震的震级介于6.4至7.7之间，但跟踪到的运动持续时间均约为2秒；其中花莲地震的运动包含地面压缩，而非仅为断层滑动。此外，与野外调查结果的对比显示，三次地震的最大速度均约为1 m/s；不过2026年熊本地震的速度历程比另外两次更复杂。已知三次地震涉及不同的地表断层位移机制，表明这些差异也可能影响位移时间历程的复杂性。
英文摘要
Surface displacements, including co-seismic fault slip, have occasionally been captured by closed-circuit television (CCTV) cameras. Such video recordings may provide information unavailable from seismometers located away from the fault. We analyzed videos of surface displacement from three earthquakes---the 2018 Hualien earthquake, the 2025 Mandalay earthquake, and the 2026 Kumamoto earthquake---using a unified methodology. We removed the effects of strong ground motion by aligning each frame so that reference regions in the image remained fixed. This analysis enables the temporal evolution and, in particular, the duration of surface displacement to be estimated. Although the three earthquakes ranged from $M_\mathrm{w}$6.4 to $M_\mathrm{w}$7.7, the tracked motion lasted approximately 2 s in all three cases; in the Hualien case, the motion included compression of the ground rather than fault slip alone. Comparison with field surveys indicates that the maximum velocity was on the order of 1 m/s in each case. The 2026 Kumamoto earthquake, however, exhibited a more complex velocity history than the other two events. The three earthquakes involved different mechanisms of surface fault displacement, suggesting that these differences may also influence the complexity of the displacement time histories.
