Geophysical Assessment of Local Geothermal Resources for Strengthening Industrial Energy Networks: A Case Study from a Heavy Industrial Area

The ongoing European energy transition and the restructuring of energy markets are increasing pressure on energy-intensive industries to reduce greenhouse gas emissions while maintaining secure and reliable energy supplies. In this context, local geothermal resources represent a promising low-carbon energy source for strengthening industrial energy resilience. This study investigates the geothermal potential of a heavy industrial area located at the northwestern margin of the Bohemian Massif (Czech Republic), where elevated heat flow is associated with the interaction of Variscan structures, post-orogenic magmatism, and Cenozoic rifting. Due to safety restrictions related to industrial infrastructure, including pipelines and zones with explosive substances, a combination of controlled-source magnetotellurics and gravimetric surveying was applied. Magnetotelluric measurements conducted in the frequency range of 8–8192 Hz identified a major fault-controlled boundary between the crystalline basement of the Saxothuringian Zone and the Neogene sedimentary fill of the Most Basin. Gravimetric modeling revealed a pronounced negative residual Bouguer anomaly that can be explained by variations in sediment thickness and/or the presence of a low-density body within the crystalline basement. The integrated interpretation of geophysical data, regional heat-flow distribution, and existing geological knowledge suggests that this low-density body may be associated with granite porphyry intrusions of the Altenberg–Teplice Collapse Caldera. The results indicate that the northwestern Bohemian Massif contains geological structures favourable for geothermal exploration and demonstrate the applicability of low-impact geophysical methods in complex industrial environments. The study provides a scientific basis for future geothermal development aimed at supporting industrial decarbonization, regional energy resilience, and long-term energy security.