Landslide dam failure hazard chains (i.e., landslide dam breaches → outburst debris flow → river blocking) are common in alpine valley regions worldwide, and they pose a great threat to human safety and infrastructure. However, the formation and dynamic processes of cascading hazards are still poorly understood, which limits our ability to recognize warning signals for this multi-hazard chain. We conducted 12 large-scale field tests on the multi-hazard chain induced by landslide dam failure, measuring the flow dynamics and the resulting seismic signals. The results showed that river blockage caused by a dam-breaching debris-flow underwent stages of injection and initial deposition, river damming and equilibration, during which the evolution of seismic signals can help interpret the physical processes and mechanisms involved. The radiated energy level resulting from the dam breaching and the debris flow increased with the diameter, speed and volume of the fluid-particles mixture; while the frequency of the seismic data increased with the speed of the fluid-mixture particles but decreased with the diameter of the particles. Greater tributary inflow discharge or dam height generally resulted in larger and more destructive outburst debris flows, characterized by greater seismic energy and a wider frequency domain, resulting in a greater degree of obstruction within the receiving channel. We also show that the seismic technique employed is an efficient means of detecting and characterizing landslide dam failure hazard chains, providing downstream warnings of a river blockage by estimating the critical blockage conditions, such as the tributary flow velocity, sediment concentration, and kinetic energy. This study provides a scientific perspective for understanding the dynamic signatures of the entire hazard chain evolutionary process and it highlights opportunities to use seismic data for multi-hazard chain research and warning.

滑坡坝溃坝危害链（即滑坡坝溃坝→溃决泥石流→河流阻塞）在世界范围内的高寒山谷地区普遍存在，对人类安全和基础设施构成极大威胁。然而，级联灾害的形成和动态过程仍然知之甚少，这限制了我们识别这种多灾害链的预警信号的能力。我们对滑坡坝溃坝诱发的多灾种链进行了 12 次大规模现场试验，测量了流动动力学和由此产生的地震信号。结果表明，溃坝泥石流造成的河流阻塞经历了注入和初始沉积、河流筑坝和平衡阶段，在此期间，地震信号的演变可以帮助解释所涉及的物理过程和机制。大坝溃坝和泥石流产生的辐射能量水平随着流体-颗粒混合物的直径、速度和体积的增加而增加；而地震数据的频率随着流体混合物粒子的速度增加而随着粒子直径的增加而降低。更大的支流流入流量或坝高通常会导致更大和更具破坏性的突出泥石流，其特征是更大的地震能量和更宽的频域，导致接收通道内的阻塞程度更大。我们还表明，所采用的地震技术是检测和表征滑坡坝破坏危险链的有效手段，通过估计支流流速等关键阻塞条件，提供河流阻塞的下游警告，泥沙浓度和动能。本研究为理解整个灾害链演化过程的动态特征提供了科学视角，并强调了将地震数据用于多灾害链研究和预警的机会。