Estudio petrológico y geoquímico de las vulcanitas de los afloramientos de El Pimpollar, extremo nororiental de la Zona Surportuguesa

Abstract

The Lower Unit of “El Pimpollar” volcanic outcrop (South-Portuguese Zone) is mainly composed of submarine dacites and andesites, with some subordinate basalts and trachyandesites. All these volcanic materials have intraplate affinities. The more basic rocks have alkaline character and show some differences with the equivalent vulcanites of the Iberian Pyrite Belt. The rhyolites of the Upper Unit are very rich in K and have geochemical characteristics intermediate between the silica rich igneous rocks related with volcanic arcs or collisional orogens. These rhyolitic rocks are different from other volcanic rocks with similar SiO2 content of the Iberian Pyrite Belt. The volcanic suite has a post-Middle-Visean age and its two units extruded in different tectono-sedimentary environments