Influence of subduction zone structure on coastal and inland attenuation in Mexico
Por:
García D., Singh S.K., Herraiz M., Ordaz M., Pacheco J.F., Cruz-Jiménez H.
Publicada:
1 oct 2009
Resumen:
Although it has been suggested in the past that the attenuation of seismic waves along the Pacific coast of Mexico and towards the continent differs, the subject has been controversial and, as yet, unresolved. Here we re-examine this issue using more extensive and higher quality data now available. Our analysis of more than 450 local and regional (R < 400 km) records from interplate earthquakes (5.0 <= M(w) <= 8.0; 10 <= H < 30 km) shows that the Fourier spectral amplitudes at inland sites exceed those at coastal ones, especially in the frequency range of 0.3-2 Hz. We find that site or source effects are not the cause of this difference. The observed disparity of amplitudes is in fact a consequence of the efficient propagation of Lg and SmS phases along the convergence direction, as it is confirmed by numerical modelling. The simulations show that the energy radiated by interplate earthquakes is efficiently guided towards the continent by the wedge-shape geometry and the structure of t
Filiaciones:
García D.:
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico
Singh S.K.:
Univ Nacl Autonoma Mexico, Inst Ingn, Mexico City 04510, DF, Mexico
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico
Herraiz M.:
Facultad de Ciencias Físicas, Universidad Complutense de Madrid (UCM), Av. Ciudad Universitaria s/n, 28040 Madrid, Spain
Ordaz M.:
Univ Nacl Autonoma Mexico, Inst Ingn, Mexico City 04510, DF, Mexico
Pacheco J.F.:
Observatorio Vulcanológico y Sismológico de Costa Rica (OVSICORI), Apdo. Postal, 2346-3000, Heredia, Costa Rica
Cruz-Jiménez H.:
Univ Nacl Autonoma Mexico, Inst Ingn, Mexico City 04510, DF, Mexico
All Open Access; Bronze
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