###### Abstract  
The Southeastern Tyrrhenian Sea is a back-arc basin characterized by the onset of volcanism over the past ~11 million years and the development of numerous volcanic seamounts. Hydrothermal venting is predominantly concentrated in the southeastern sector, encompassing the Aeolian volcanic arc and major volcanic edifices, such as Palinuro and Marsili. These systems frequently exhibit zones of localized magnetic depletion (demagnetization) within otherwise magnetized volcanic structures, often linked to hydrothermal alteration. Notably, volcanic rejuvenation phases are commonly associated with active hydrothermal circulation. In response to mounting ecological concerns, the Italian government has delineated extensive Ecological Protection Zones (EPZs), including those in the Eastern Tyrrhenian sector. These EPZs encompass a series of prominent seamounts\(-\)Palinuro, Marsili, Vercelli, Vavilov, Magnaghi, Enarete, and Anchise\(-\)that exhibit morphological evidence of rejuvenation and magnetic anomalies consistent with hydrothermal modification. Such features are indicative of potentially mineralized systems, relevant for future resource exploration. A comprehensive evaluation of both the ecological significance and the mineral potential of these areas is now imperative. Balancing environmental conservation with the strategic assessment of deep-sea mining prospects will be essential to mitigate biodiversity loss while promoting the sustainable use of marine mineral resources. seamounts; hydrothermal vents; exclusive economic zone; environmental protection zone; residual magnetic anomalies; volcanic rejuvenation; demagnetization 2025 15 6174 2025 15 6  
environmental impacts of deep-sea mining. Many scientists argue that the precautionary principle should be applied to this industry, meaning that mining should not proceed until its potential impacts have been fully assessed [1; 2; 3]. There are concerns about the potential impacts linked to the process of extraction, which can disrupt fragile oceanic ecosystems, while the release of sediment and other materials into the water column during the extraction and processing of minerals can have negative effects on marine life [4; 5; 6; 7]. Moreover, there is still much that is unknown about the long-term effects of removing large quantities of nodules from the ocean floor and the impact of large-scale sediment plumes generated by mining vehicles [8; 9]. Finally, several studies pointed out the risks related to the release of toxic chemicals into the ocean during the extraction and processing phases [10]. Despite these concerns, interest in potential marine mining resources continues to grow. In fact, deep-sea minerals hold significant potential due to their abundant deposits, mainly consisting of polymetallic nodules (deep-sited seafloor), Fe-Mn crusts (on seamounts), and massive sulfides (on hydrothermal chimneys). According to conservative estimates in the Clarion-Clipperton Zone (CCZ, Pacific Ocean), quantitative studies indicate potential stocks of around 21.1 billion dry metric tons of polymetallic nodules, which equates to 600% of the world's existing terrestrial reserves of cobalt, 340% of nickel, 30% of copper, and more than 100% of manganese [11; 12; 13]. Other, more accessible (shallower) potential sites of marine resources have also been identified and confirm the overall potentiality [14], which is especially related to back-arc basins. The purpose of this manuscript is to shed light on the state of the art of the knowledge of hydrothermal vents of the SE Tyrrhenian basin (Western Mediterranean Sea; Figure 1A), where there is a strong inclination to further explore the economic aspects of the frontier constituted by deep-sea mining, in terms of private companies that greatly believe in the potential and future of this sector. The SE Tyrrhenian Sea is a geodynamically unique area, shaped by active back-arc extension above a subducting slab, which has led to the formation of one of the highest concentrations of volcanic seamounts in the Mediterranean.