Envelope of coda waves for a double couple source due to non-linear elasticity

Calisto, I.; Bataille, K

Abstract

Non-linear elasticity has recently been considered as a source of scattering, therefore contributing to the coda of seismic waves, in particular for the case of explosive sources. This idea is analysed further here, theoretically solving the expression for the envelope of coda waves generated by a point moment tensor in order to compare with earthquake data. For weak non-linearities, one can consider each point of the non-linear medium as a source of scattering within a homogeneous and linear medium, for which Green's functions can be used to compute the total displacement of scattered waves. These sources of scattering have specific radiation patterns depending on the incident and scattered P or S waves, respectively. In this approach, the coda envelope depends on three scalar parameters related to the specific non-linearity of the medium; however these parameters only change the scale of the coda envelope. The shape of the coda envelope is sensitive to both the source time function and the intrinsic attenuation. We compare simulations using this model with data from earthquakes in Taiwan, with a good fit.

Más información

Título según WOS: Envelope of coda waves for a double couple source due to non-linear elasticity
Título según SCOPUS: Envelope of coda waves for a double couple source due to non-linear elasticity
Título de la Revista: GEOPHYSICAL JOURNAL INTERNATIONAL
Volumen: 199
Número: 1
Editorial: OXFORD UNIV PRESS
Fecha de publicación: 2014
Página de inicio: 382
Página final: 390
Idioma: English
DOI:

10.1093/gji/ggu210

Notas: ISI, SCOPUS