Las curvas de dispersión continentales se obtuvieron de las velocidades de grupo de ondas de Rayleigh para seis sismos con epicentros en el Atlántico Sur. La inversión sugiere una corteza superior sedimentaria, con velicidades de S de 1.32-2.90 km/s, seguida por un basamento cristalino de 3.06-3.38 km/s. La corteza inferior is transicional (4.02-4.22 km/s) como en otros bordes continentales pasivos. La base de la corteza se encuentra a 36±4 km pero existen valores menores en los perfiles A a C.Source-station Rayleigh wave group velocities are decomposed to obtain pure continental shelf dispersion curves along three profiles. Inversion results of these dispersion curves indicate that the upper crust is dominated by sediments and high velocity sedimentary rocks with shear wave velociies varying from 1.32 to 2.90 km/s. The intermediate crusal layer has assumed shear wave velocities typical of crystalline basement (3.06≤β≤4.22 km/s), similar to those observed at other passive continental margins (e.g., Dainty et al.,1966; Calcagnile et al., 1982). These results are in agreement with those of a recent surface wave study conducted in the same area (Souza, 1995). Moho boundary is cleary defined around 36±4 km depth, but a reduction in the crustal thickness is observed from profile A to C.