S wave velocity structure below central Mexico using high-resolution surface wave tomography
Article first published online: 15 JUN 2010
Copyright 2010 by the American Geophysical Union.
Journal of Geophysical Research: Solid Earth (1978–2012)
Volume 115, Issue B6, June 2010
How to Cite
2010), S wave velocity structure below central Mexico using high-resolution surface wave tomography, J. Geophys. Res., 115, B06307, doi:10.1029/2009JB006332., , , , , , and (
- Issue published online: 15 JUN 2010
- Article first published online: 15 JUN 2010
- Manuscript Accepted: 11 JAN 2010
- Manuscript Revised: 15 DEC 2009
- Manuscript Received: 26 JAN 2009
- surface wave tomography;
- structure below central Mexico;
 Shear wave velocity of the crust below central Mexico is estimated using surface wave dispersion measurements from regional earthquakes recorded on a dense, 500 km long linear seismic network. Vertical components of regional records from 90 well-located earthquakes were used to compute Rayleigh-wave group-velocity dispersion curves. A tomographic inversion, with high resolution in a zone close to the array, obtained for periods between 5 and 50 s reveals significant differences relative to a reference model, especially at larger periods (>30 s). A 2-D S wave velocity model is obtained from the inversion of local dispersion curves that were reconstructed from the tomographic solutions. The results show large differences, especially in the lower crust, among back-arc, volcanic arc, and fore-arc regions; they also show a well-resolved low-velocity zone just below the active part of the Trans Mexican Volcanic Belt (TMVB) suggesting the presence of a mantle wedge. Low densities in the back arc, inferred from the low shear wave velocities, can provide isostatic support for the TMVB.