Three-dimensional resistivity imaging of Pantelleria Island: Insights into its geothermal potential

The island of Pantelleria, located in the Sicily Channel, is a volcanic system characterized by peralkaline (pantelleritic) magmatism and recurrent explosive eruptions, which have produced prominent caldera structures. Active geothermal manifestations, including gas emissions, hot springs, and elevated temperatures detected in deep boreholes, underscore its potential as a geothermal resource. To elucidate the island's subsurface and enhance the understanding of its volcanic structures, geothermal reservoirs, and the pathways of hydrothermal fluid circulation, a magnetotelluric (MT) survey was performed, including 78 independent measurements. The resulting three-dimensional resistivity model delineates the geological and geothermal framework down to a depth of 2.5 km below sea level. The resistivity anomalies imaged by the 3D electrical model can be associated with specific geological processes and physical conditions within the geothermal system, accurately identifying the main volcano-tectonic structures, particularly the rims of the La Vecchia and Cinque Denti calderas which drive the hydrothermal system's fluid circulation and storage. This study highlights the fundamental role of caldera structures in influencing hydrothermal processes and improves our understanding of Pantelleria's geothermal potential. The results provide valuable insights for targeted exploration and sustainable exploitation of the island's geothermal resources.