Unveiling the Complexity of Monogenetic Volcanic Fields: A Petrological Exploration of the Puig Jordà (Garrotxa Volcanic Field, Spain).

This article focuses on the magmatic processes and plumbing system architecture of the Puig Jordà monogenetic eruption (17 ka) within the Garrotxa Volcanic Field (GVF) in northeastern Spain. Through detailed volcano-stratigraphic, petrological, and geochemical analyses of pyroclastic deposits and lava flows, the study reveals a complex multi-stage magma ascent involving rapid rise from deep mantle sources (~900–1200 MPa, 1200–1250°C), interaction with previously emplaced shallow magma pockets (600–900 MPa, 1175 ± 15°C), and final ascent through shallow crustal levels (~120 MPa, 1110 ± 30°C). The research also questions the previously assumed link between the Puig Jordà eruption and the Bosc de Tosca lava flow, suggesting either a different source for the lava or the involvement of two distinct magmas during the eruption. These findings have implications for volcanic hazard assessment and monitoring in the GVF and similar monogenetic volcanic fields, highlighting the importance of recognizing multi-level magma storage and ascent histories.