The role of mantle and crust in the generation of calc-alkaline Variscan magmatism and its tectonic setting in the Eastern Pyrenees

The lower structural levels of the Variscan orogen exposed in Eastern Pyrenees reveal three genetically associated magmatic suites: (i) a batholitic sized calc-alkaline granitoid (Sant Llorenç – La Jonquera, SL–LJ); (ii) minor mafic intrusions with local ultramafic cumulates (Ceret and Mas Claret complexes); (iii) peraluminous leucogranite bodies. These suites were emplaced syn- to post-collisional setting during Late Carboniferous Early Permian (ca. 315–290 Ma) an Upper Proterozoic-Upper Ordovician metasedimentary sequence. We carried out field petrographic work whole-rock geochemistry (including SrNd radiogenic isotopes) order constrain petrogenetic relationships between them determine interplay igneous country rock. compare geochemical data those from neighbouring massifs Catalan Coastal Ranges. granitoids complexes underwent variable degrees crustal assimilation as demonstrated by Sr Nd isotopic ratios SL–LJ rocks. Contaminated gabbro-diorites are high Fe Zr contain garnet equilibrium FeMg amphibole. A supra-subduction metasomatized mantle source for is inferred. magma that formed was intermediate composition may have differentiation magmas derived partial melting subduction-metasomatized caused active subduction or delamination crust triggered underplating mantle-derived magmas. Leucogranite later rocks compositions similar outcropping metapelites orthogneisses. deduce retrograde cooling decompression path 0.75 GPa down 0.55 phase equilibria garnet-bearing diorite. This compatible extensional context linked regional dextral strike-slip regime provided space ascent emplacement pluton. system consistent late-Variscan shear zones displacing Gondwana west respect Laurasia orogenic collapse.