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Located in the northern part of continental Portugal, the city of Porto is characterized by low-to-moderate levels of seismicity, thus one of reasons for the lack of studies regarding the influence of site effects in this area. In this study, the HVSR technique (horizontal-to-vertical spectral ratio) was used in order to obtain information about the fundamental frequencies of the ground in several parts of the city which was later compared to the geotechnical information presented in the Geotechnical Map of Porto,...

The geophysical surveys methods have not been extensively used in gold exploration in Northern Portugal. This is based on the fact that most mineralized zones contain low and erratic sulphide contents. In this work were tested three different types of geophysical surveys combined with geochemical surveys, in order to define anomalies that are closely correlated with the locations of known mineralized zones. The aim of the work is to study some gold deposits in Northern Portugal (Lagoa Negra and Castromil) with the...

The present work shows some results obtained by the Time-Domain Electromagnetic Method (TDEM) to help characterize the geology and Penacova- RпїЅgua-Verin fault structure in the Vila Pouca de Aguiar sector. The Fault is an important tardi-variscan structure with NNE-SSW direction, more than 500 km long, extending from the North of Spain until near NazarпїЅ. The application of the TDEM method aimed to acquire data towards obtaining profiles of subsurface electrical resistivity in the zone affected by the fault and ...