Geoelectricals Surveying in Aluvional Sediments of Madeira River (Porto Velho/Ro)

The construction of two hydroelectric dams in Madeira River, near to Porto Velho city, will force the dredges, which explore residual gold in the stream bed, to change the location. The purpose of this work was to identify the auriferous conglomerate from Mucururu Formation using geophysical studies. Vertical electrical soundings (VES) and continuous vertical electrical sounding (CVES) were done in pre-determined places by geologists. In total were done 52 VES and 9 lines of CVES.<br>After an integration of geophysical data and geological observation were determined the most propitious places to have this auriferous conglomerate. A borehole with lithological description is suggested in some points to a better calibration of the model.