Imageamento da Subsuperfície Rasa Com Gpr Nas Vizinhanças de Fontes Naturais Existentes no Município de São Sebastião do Passé-Ba

We employ the geophysical method named GPR (Ground Penetrating Radar) to investigate the shallow subsurface in the vicinity of natural water sources in São Sebastião do Passé, Bahia. In these surveys, we used an antenna with center frequency of 200 MHz, using a constant offset configuration. It were acquired 14 profiles in four localities of the city: Banco de Areia, Capivara e Água Preta where outcrops the sediments of São Sebastião Formation and Km 2 where outcrops the Barreiras Group. The data were processed using a basic flow, which includes: the application of gains, time domain filtering, conversion to depth and static correction. The radargramas processed were then interpreted, making it possible to identify lithologic contacts, sedimentary structures such as laminations and stratification, and also reflectors corresponding to the shallow water table. It was still possible to determine the saturated zone through the reflection pattern, as also were found buried pipes and wires, as revealed by diffraction hyperbolae. Finally, we proved the applicability of the method in characterizing heterogeneity of electrical and electromagnetic properties associated with the geological structures in the shallow subsurface.