Caracterización petrológica y geoquímica del sector central del batolito de Los Pedroches: discriminación de dos series de granitoides

Abstract

A petrographic and geochemical study is presented on igneous rocks and enclaves from Los Pedroches Batholith (Southern Central Iberian Zone, Iberian Massif, Spain), making use of both original and previously published data. A marked contrast between two granitoid series is clear in the batholith, both in petrographic and chemical features, especially when data from enclaves are considered. If (accidental) xenoliths are excluded, each series has its characteristic enclave population, with distinctive structural, petrographic and chemical features. Moreover, for each series, enclaves and hosts are systematically related, as shown by ratios MgO/MgO+FeO*, MgO/TiO2, MgO/Li, K2O/Rb, Ba/Rb, Sr/Ba, and TiO2/Zr, among other chemical features. Each series has a distinctive enclave-host geochemical pattern. We conclude that any petrogenetic model for the Los Pedroches area has to take in account the existence of these contrasted granitoid series, prior to evaluating processes such as differentiation or magma mixing.