U-Pb geochronology of felsic volcanic rocks hosted in the Gafo Formation, South Portuguese Zone: the relationship with Iberian Pyrite Belt magmatism

摘要

Felsic volcanic rocks exposed in the Frasnian Gafo Formation, in the Azinhalinho area of Portugal, display very similar geochemical signatures to volcanic rocks from the Iberian Pyrite Belt (IPB), located immediately to the south. The similarities include anomalously low high field-strength elements (HFSE) concentrations, possibly caused by low-temperature crustal melting, which translate into classification problems.