Refinements to the method of epicentral location based on surface waves from ambient seismic noise: introducing Love waves

Geophysical Journal International
By: , and 

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Abstract

The purpose of this study is to develop and test a modification to a previous method of regional seismic event location based on Empirical Green’s Functions (EGFs) produced from ambient seismic noise. Elastic EGFs between pairs of seismic stations are determined by cross-correlating long ambient noise time-series recorded at the two stations. The EGFs principally contain Rayleigh- and Love-wave energy on the vertical and transverse components, respectively, and we utilize these signals between about 5 and 12 s period. The previous method, based exclusively on Rayleigh waves, may yield biased epicentral locations for certain event types with hypocentral depths between 2 and 5 km. Here we present theoretical arguments that show how Love waves can be introduced to reduce or potentially eliminate the bias. We also present applications of Rayleigh- and Love-wave EGFs to locate 10 reference events in the western United States. The separate Rayleigh and Love epicentral locations and the joint locations using a combination of the two waves agree to within 1 km distance, on average, but confidence ellipses are smallest when both types of waves are used.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Refinements to the method of epicentral location based on surface waves from ambient seismic noise: introducing Love waves
Series title Geophysical Journal International
DOI 10.1111/j.1365-246X.2012.05631.x
Year Published 2012
Language English
Publisher Wiley
Contributing office(s) Geologic Hazards Science Center
Description 15 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Geophysical Journal International
Country United States