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In the Central Iberian Zone, multiple subvolcanic intrusions were emplaced during the final stages of the Variscan orogeny. The felsic component of this magmatic episode is mainly represented by dykes and masses of granite porphyries and microgranites, which can be commonly found in northern Portugal. Overall, these rocks are more evolved and enriched in rare incompatible metal elements (such as Li, Be, Rb, Cs, Nb, Ta, Sn, and W) when compared to the regional Variscan granites. The data acquired from the lithogeoc...

This work is a mineral chemistry study of the pyroxene crystals composing a microgabbro dyke found in the Vila Nova de Foz Coa (VNFC) region of northern Portugal. Several pyroxene geothermometers and geobarometers have also been employed to infer the likeliest thermodynamic conditions of crystallization. Following the IMA 1988 report for the nomenclature of pyroxene minerals, the VNFC microgabbro is rich in Ca-Mg-Fe species. The studied clinopyroxenes are aluminian, chromian, and/or ferroan diopside and augite, wh...

Multiple veins of subvolcanic lithologies, including porphyries, lamprophyres and dolerites, outcrop in northern Portugal intruding both the pre-variscan metasedimentary basement (known as the Schist-Greywacke Complex) and variscan granites of high compositional variability. The N-S trending, granitic/rhyolitic porphyries of Vila Pouca de Aguiar (VPA) constitute two of the most important examples of these veins. Both porphyries intrude the main facies of the regional pluton (the VPA granite). The present study con...

In the portuguese section of the Central Iberian Zone, the Guimaraes region hosts a wide diversity of plutonic variscan lithologies including biotite-rich granitoids and vaugnerites. Vaugnerite outcrops occur as small bodies, typically enclosed by the main regional granite (the coarse-grained, biotite-rich, porphyritic Guimaraes and Santo Tirso monzogranite). Mafic enclaves of vaugnerites can also be identified in the host granite. The granitoids are peraluminous (ASI = 1.10 ? 1.15), having crystallized from melts...