"In subduction zones, chemical elements are transferred between different reservoirs of the Earth (i.e., the atmosphere, the hydrosphere, the lithosphere and the asthenosphere) and important amounts of magmas are generated. Reactions involving volatiles are fundamental in mobilizing elements in subduction zones and they significantly influence the composition of the associated arc magmas, which show a characteristic enrichment in Large-Ion Lithophile Elements relative to the High-Field Strength Elements.There is an increasing agreement that one of the most important reactions that generates fluids in subduction zones and triggers the arc magmatism is the dehydration of antigorite serpentinite to prograde chlorite harzburgite.Here, I propose to carry out a detailed geochemical study of the ultramafic rocks from the Cerro del Almirez (southern Spain), which is the only natural example worldwide preserving the high-pressure dehydration of antigorite-serpentinite into prograde peridotite. Major, trace element and radiogenic isotopic analyses of whole-rocks and minerals from samples located across the serpentinite-harzburgite transition will be performed. This study will provide new insight into how lithophile and siderophile elements behave during the dehydration of serpentinite, how they are transferred between the different components of the subduction zone and how they influence the composition of the slab-derived fluids and arc magmas. This project will contribute to the transfer of knowledge of cutting-edge techniques on isotope analysis and to increase the international leadership of the host in the geochemistry of subduction zones, concurrently strengthening its cooperation with internationally-reputed European centres in Earth Sciences. The award of this reintegration grant will permit to reinforce my personal skills in analytical and theoretical geochemistry and will be fundamental for obtaining a permanent position as a research scientist at the host."