Rockfalls generate seismic signals that can be used to detect and monitor rockfall activity. Event locations can be estimated on the basis of arrival times, amplitudes, or polarization of these seismic signals. However, surface topography variations can significantly influence seismic wave propagation and hence compromise results. Here, we specifically use the signature of topography on the seismic signal to better constrain the source location. Seismic impulse responses are predicted using Spectral Element based simulation of three‐dimensional wave propagation in realistic geological media. Subsequently, rockfalls are located by minimizing the misfit between simulated and observed inter‐station energy ratios. The method is tested on rockfalls at Dolomieu crater, Piton de la Fournaise volcano, Reunion Island. Both single boulder impacts and distributed granular flows are successfully located, tracking the complete rockfall trajectories by analyzing the signals in sliding time windows. Results from the highest frequency band (here 13–17 Hz) yield the best spatial resolution, making it possible to distinguish detachment positions less than 100 m apart. By taking into account surface topography, both vertical and horizontal signal components can be used. Limitations and the noise robustness of the location method are assessed using synthetic signals. Precise representation of the topography controls the location resolution, which is not significantly affected by the assumed impact direction. Tests on the network geometry reveal best resolution when the seismometers triangulate the source. We conclude that this method can improve the monitoring of rockfall activity in real time once a simulated database for the region of interest is created.

中文翻译：

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使用地震能量的站间比率确定落石量，位于皮腾·德拉富尔纳瓦火山Dolomieu火山口

落石产生地震信号，可用于检测和监视落石活动。可以根据这些地震信号的到达时间，幅度或极化来估计事件位置。但是，表面形貌的变化会显着影响地震波的传播，因此会影响结果。在这里，我们专门使用地震信号的地形特征来更好地约束震源位置。地震脉冲响应是通过使用基于频谱元素的三维波在真实地质介质中传播的模拟来预测的。随后，通过最小化模拟和观测到的站间能量比之间的不匹配来确定落石的位置。该方法在留尼汪岛Piton de la Fournaise火山Dolomieu火山口的落石处进行了测试。通过分析滑动时间窗口中的信号，可以成功定位单个巨石撞击和分布的颗粒流，从而跟踪完整的落石轨迹。最高频段（此处为13–17 Hz）的结果可产生最佳的空间分辨率，从而可以区分相距小于100 m的分离位置。通过考虑表面形貌，可以同时使用垂直和水平信号分量。使用合成信号评估定位方法的局限性和噪声鲁棒性。地形的精确表示控制位置分辨率，不受假定的碰撞方向的明显影响。当地震仪对震源进行三角剖分时，对网络几何形状的测试显示出最佳分辨率。