Geochemical prospecting and panning method at the Coriscada zone (Beira Alta - Portugal). Comparative essay of methodologies

Abstract

The studie area (16Km2) is situated to the south of Meda (Beira Alta - Portugal). In the geological point of view two great units predominate in the area: a hercinian medium-grain and two-mica granite and schist-granite-migmatite complex. The complex components are, however, difficult to separate.The comparative study of the score factors mapping, the W and Sn geochemical anomalies mapping and the cassiterite, volframite and schellite panning maps leads to the conclusion that the panning method is suitable to obtain a prior delimitation of the W and Sn anomalous areas.Nevertheless, the panning procedure cannot dispense the geochemical prospecting, since the utilisation of multivariate statistical analysis of geochemical data shows more representative images of geological context and mineralizations occuring in the area.