Analysis of Seismic Signals Generated by Vehicle Traffic with Application to Derivation of Subsurface Q Values
Session: Critical Zone, Environmental and Cryospheric Seismology
Type: Oral
Date: 4/22/2021
Presentation Time: 05:45 PM Pacific
Description:
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 to 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.
Presenting Author: Haoran Meng
Student Presenter: No
Authors
Haoran Meng Presenting Author Corresponding Author h2meng@ucsd.edu Scripps Institution of Oceanography, University of California, San Diego |
Yehuda Ben-Zion benzion@usc.edu University of Southern California |
Christopher Johnson cwj@lanl.gov Los Alamos National Laboratory |
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Analysis of Seismic Signals Generated by Vehicle Traffic with Application to Derivation of Subsurface Q Values
Category
Environmental and Cryospheric Seismology: Deriving Insights from Ice, Avalanches and Beyond