thumbnail

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

Geophysical Journal International

By:
, , , ,
DOI: 10.1111/j.1365-246X.2012.05631.x

Links

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