Jaramillo-Rios J. S. auteur aut IRD Espinoza-Otayza J. A. auteur aut IRD Ramirez-Briones J. auteur aut IRD Valverde-Rodriguez P. E. auteur aut IRD Vallance J. auteur aut IRD Tavazzani L. auteur aut IRD Chelle-Michou C. auteur aut IRD de Haller A. auteur aut IRD Chiaradia M. auteur aut IRD Spikings R. A. auteur aut IRD Zanetti K. A. auteur aut IRD Konrad K. auteur aut IRD Baby Patrice auteur aut IRD Melgarejo J. C. auteur aut IRD Torró L. auteur aut IRD text journalArticle eng text/pdf born digital access The Central Andes constitute a key natural laboratory for studying the tectono-magmatic response to subduction beneath thick continental crust and the formation of associated ore deposits. In the Bolivian back-arc region, world-class Sn-polymetallic deposits of the Huanuni district are spatially associated with rhyolitic dikes and voluminous peraluminous pyroclastic deposits related to the Morococala Volcanic Field. New geochronological data indicate that the peraluminous rhyolitic dikes in Huanuni were coeval and likely part of the same magmatic plumbing system at ca. 7.0-6.4 Ma, and hence are not associated with the Oligocene-Miocene Sn-polymetallic mineralization (ca. 24 Ma). Mixing models based on Nd-Sr isotopic compositions of the Morococala Volcanic Field, supported by Monte Carlo simulations, suggest crustal contributions of similar to 45-70%. These are, in general, concordant with the similar to 50:50 mantle-derived melts and continental crust mass balance models proposed for other ignimbrite fields of the Neogene Ignimbrite Province of the Central Andes in the back-arc region (e.g., Los Frailes Volcanic Field and the Panizos, Coranzuli, Vilama, and Ramadas fields within the Altiplano-Puna Volcanic Complex). Mineralogical and geochemical evidence suggests that the associated magmas formed under thick-crustal conditions, with garnet as a residual phase. The voluminous rhyolitic magmatism in the Morococala Volcanic Field likely resulted from hot mantle upwelling induced by slab re-steepening of the subducted slab after a flat-slab episode. specialized Ignimbrite Peraluminous magmatism Neogene ignimbrite province of the Central Andes Central Andean tin belt Geochronology BOLIVIE ANDES MOROCOCALA VOLCAN 064 021 179 106112 [25 p.] 2026 0895-9811 https://www.documentation.ird.fr/hor/fdi:010097359 10.1016/j.jsames.2026.106112 0895-9811 [F B010097359] https://www.documentation.ird.fr/hor/fdi:010097359 https://www.documentation.ird.fr/intranet/publi/2026-07/010097359.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2026-07-09 2026-07-09 fdi:010097359 fre