This work presents an application of the Transient Electromagnetic geophysical method in the area of Basin of Resende, Rio de Janeiro, Brazil. ln this basin, it was made in 2001, a geophysical survey of 88 soundings seeking to contribute for the knowledge of the hydrogeological potential of the area. This area is densely industrialized, so noise tends to hinder the use of the method. The data were interpreted using an 1-D inversion algorithm where the resistivity in depth is estimated from the induced voltage time decay. Surface shows highly conductive layers (~5Ω.m) and the value of 200Ω.m for the transition resistivity coresponding to the geoelectric basement was suggested from lithology and stratigraphy data of the basin together with a fine adjustment gauged in the 3-D gravity model of the basin. From the 1-D inversion we built up a pseudo-3D geoelectric image of the basement geometry. Despite the physical properties involved (density and resistivity) does not have any relationship between them, the topography of a previous gravity basement was used to estimate depths that were not reached by the TEM signal. The resulting surface has a topography which is assumed be representative of the basin's basement. So, the use the TEM method in Basin of Resende allowed to estimate the lateral limits of the basin and to propose limits in depth. Three areas can be depicted: a structural high flanked by two structural lows (depocenters), one to east and the other to west of the basin.
transient electromagnetic method; Basin of Resende; geoelectrical structure
