Modelado sísmico de la cuenca de la Ciudad de México

Abstract

Numerical results are presented of seismic modeling with finitp differences on a staggered grid. Stable, precise and reliable solutions for the Mexico City basin arc obtained. The response of simplified geologic models suggests that the influence of the deep subsoil (down to 1.5 km) can be important in ground motion evaluation for low frequencies (0.5-1.5 Hz). Spatial variations and long duration of ground 'motion in Mexico City may be due, among other possible causes, to the induction, due to the closed basin effect, of surface waves propagating laterally and in opposite directions. Uncertainties should be solved as we know better the structure of the subsoil and the incident seismic wavefield, as our ability to model the structure improves, and by studying the large horizontal ground motion displacement observed in acceleration records.