Crustal structure of south-central Mexico estimated from the inversion of surface-wave dispersion curves using genetic and simulated annealing algorithms

Abstract

We have computed group velocities of the fundamental mode of Rayleigh waves along two paths using broadband seismograms of fourteen subduction-zone earthquakes in Mexico. One path crosses the Guerrero terrane while the other traverses the Oaxaca terrane. The dispersion curves have been inverted for crustal structure using genetic and simulated annealing algorithms. Our results show significant differences in crustal structure beneath the Guerrero and the Oaxaca terranes, especially in velocity of the superficial layer and Moho depth. The genetic algorithm (GA) is considerably faster than the simulated annealing algorithm (SA). On the other hand, the SA requires a small computer memory. Another significant advantage of SA is that it reaches a smaller misfit value than GA.

Keywords

• Genetic algorithm
• simulated annealing
• surface-wave dispersion
• crustal structure of Mexico