Geologic map of the Valencia del Ventoso Variscan igneous complex (SW Iberian Massif, Spain): an example of multi-stage intrusion building by contrasted magma compositions

Abstract

A map of the areal distribution of lithotypes within the Valencia del Ventoso igneous complex (ca. 130 km2) is presented. The complex is located in the southern Ossa-Morena Zone of the Iberian Massif (Variscan Foldbelt, Spain). Field and laboratory data reveal an intricate geological context resulting from multiple, compositionally contrasted, melt pulses emplaced over a short time period. According to field relationships and lithotype characteristics, four main plutonic intrusions and two dyke swarms are discerned within the complex. Firstly, three small (<10 km2) stocks (Medina de las Torres, Valencia del Ventoso, and Pozuelo) were emplaced aligned N40E. These are composed of massive and banded gabbro, gabbrodiorite, diorite, quartzdiorite, quartzmonzodiorite and tonalite. The Valencia del Ventoso main pluton (ca. 100 km2) has been intruded, in order of emplacement, a Basic Unit of gabbro and quartzdiorite in the central area of the complex, and an Acid Unit of quartzmonzodiorite, granodiorite and monzogranite in outermost areas and through the Basic Unit. Finally, two E-W trending dyke swarms were emplaced. The first one, rhyolitic in composition, relates to the most evolved residual liquids of the plutonic association. The second one accounts for a different magmatism, Late Permian to Triassic in age, and includes rhyolite, trachyte, latite, andesite and basalt lithotypes. The geologic map of the Valencia del Ventoso plutonic complex at 1:25,000 scale is presented on a high-resolution digital terrain model base as a reference for field-oriented geologic studies in igneous petrology.