Analysis of Seismic Signals Generated by Vehicle Traffic with Application to Derivation of Subsurface Q-Values
Analysis of Seismic Signals Generated by Vehicle Traffic with Application to Derivation of Subsurface Q-Values
复制标题
车辆交通产生的地震信号分析及其地下 Q 值推导的应用
DOI：
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
C. Johnson
中科院分区：
文献类型：
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作者：
Haoran Meng;Y. Ben‐Zion;C. Johnson
正确识别和模拟地面运动的人为源对许多研究都非常重要，包括小地震探测和地表以下地震特性成像。为了理解普通车辆交通产生的信号，我们在圣哈辛托断裂带的两个地点使用与道路垂直的紧密间隔地震检波器记录的地震数据。为了量化记录的地面运动的时空和频率变化，我们开发了一个简单的解析解，用于计算表面波的传播和衰减。该模型再现了由靠近道路的检波器记录的汽车信号的良好观测钟形频谱图，并可用于估计地下材料的频率相关q值。数据分析表明，两个检查地点的道路接收器路径的频率高达150 Hz， q值为3-40。所得的q值与以往用其他方法得到的表面波衰减系数一致。分析结果和分析程序为浅层次表层材料的q值计算提供了一种高效的方法。
Correct identification and modeling of anthropogenic sources of ground motion are of considerable importance for many studies, including detection of small earthquakes and imaging seismic properties below the surface. To understand signals generated by common vehicle traffic, we use seismic data recorded by closely spaced geophones normal to roads at two sites on San Jacinto fault zone. To quantify the spatiotemporal and frequency variations of the recorded ground motions, we develop a simple analytical solution accounting for propagation and attenuation of surface waves. The model reproduces well-observed bell-shaped spectrograms of car signals recorded by geophones close to roads, and it can be used to estimate frequency-dependent Q-values of the subsurface materials. The data analysis indicates Q-values of 3–40, for frequencies up to 150 Hz for road-receiver paths at the two examined sites. The derived Q-values are consistent with attenuation factors of surface waves previously obtained with other methods. The analytical results and analysis procedure provide a highly efficient method for deriving Q-values of shallow subsurface materials.