Crustal structure beneath Mexico from receiver functions

Abstract

We present the main characteristics of the crust in the Mexican territory as inferred from analysis of converted teleseismic waves. Teleseismic signals registered at 33 stations of Mexico's National Seismological Service (Servicio Sismologico Nacional) broadband network were collected and processed to obtain receiver functions (RFs). The RFs were analyzed to get optimal depth values of the major litho-logical interfaces and velocity ratios (kappa = V-P/V-S) under the seismic stations. Through stacking of the RFs and comparison with the individual signals, we obtained estimates of the depth of the Moho with average uncertainties of similar to 3.8 km, the depth of a prominent intracrustal interface, and in some cases, the depth of the base of the oceanic crust. The crustal thickness varies from 11 to 42 km and the velocity ratios (V-P/V-S) from 1.60 to 2.10 along the country.