Anomalias gravimetricas y espesor de corteza en la region de Oaxaca, México

Abstract

Bouguer, free-air and isostatic anomaly maps of Oaxaca State are presented, using data from three transects: Puerto Angel to Teotitlán del Camino, Puerto Angel to Salina Cruz, and Puerto Angel to Punta Maldonado. Our structural interpretation is supported by available seismic refraction experiments. Crustal thickness is around 26.5 km between Punta Maldonado and Salina Cruz. The oceanic slab is 4 km thick and is subducted atan angle of 14.5°. The upper mantle density is 3.21 g/cm3. Inland from Puerto Angel we find a possible intrusive body with a density of 2.9 g/em 3. Along the coast from Puerto Angel we observe a horst in the northem section, anda graben in the southem section. Crustal densities vary between 2.53 g/cm3 (shallow units)  to 2.81 g/cm3 (deeperunits).