Ground-motion residuals, path effects, and crustal properties: A pilot study in southern California

Journal of Geophysical Research B: Solid Earth
By: , and 

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Abstract

To improve models of ground motion estimation and probabilistic seismic hazard analyses, the engineering seismology field is moving toward developing fully nonergodic ground motion models, models specific for individual source‐to‐site paths. Previous work on this topic has examined systematic variations in ground‐motion along particular paths (from either recorded or simulated earthquake data) and has not included physical properties of the path. We present here a framework to include physical path properties, by seeking correlations between ground motion amplitudes along specific paths and crustal properties, specifically seismic velocity and anelastic attenuation, along that path. Using a large data set of small‐magnitude earthquakes recorded in Southern California, we find a correlation between the gradient of seismic S wave velocity and the path term residual, after accounting for an average geometric spreading and anelastic attenuation, indicating that heterogeneity in crustal velocity primarily controls the path‐specific attenuation. Even in aseismic regions, details of path‐specific ground motion prediction equations can be developed from crustal structure and property data.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Ground-motion residuals, path effects, and crustal properties: A pilot study in southern California
Series title Journal of Geophysical Research B: Solid Earth
DOI 10.1029/2018JB016796
Volume 124
Issue 6
Year Published 2019
Language English
Publisher American Geophysical Union
Contributing office(s) Earthquake Hazards Program, Earthquake Science Center
Description 16 p.
First page 5738
Last page 5753
Country United States
State California