Strong SH-to-Love wave scattering off the Southern California Continental Borderland

Geophysical Research Letters
By: , and 

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Abstract

Seismic scattering is commonly observed and results from wave propagation in heterogeneous medium. Yet, deterministic characterization of scatterers associated with lateral heterogeneities remains challenging. In this study, we analyze broadband waveforms recorded by the Southern California Seismic Network and observe strongly scattered Love waves following the arrival of teleseismic SH wave. These scattered Love waves travel approximately in the same (azimuthal) direction as the incident SH wave at a dominant period of ~10 s but at an apparent velocity of ~3.6 km/s as compared to the ~11 km/s for the SH wave. Back-projection suggests that this strong scattering is associated with pronounced bathymetric relief in the Southern California Continental Borderland, in particular the Patton Escarpment. Finite-difference simulations using a simplified 2-D bathymetric and crustal model are able to predict the arrival times and amplitudes of major scatterers. The modeling suggests a relatively low shear wave velocity in the Continental Borderland.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Strong SH-to-Love wave scattering off the Southern California Continental Borderland
Series title Geophysical Research Letters
DOI 10.1002/2017GL075213
Volume 44
Issue 20
Year Published 2017
Language English
Publisher American Geophysical Union
Contributing office(s) Earthquake Science Center
Description 8 p.
First page 10208
Last page 10215
Country Mexico, United States
State California