A New Stage of Integrated Geophysical Investigations Along the Vyborg–Suojärvi Profile (Northern Ladoga Region)

The Raahe–Ladoga Zone, marking the boundary between the Karelian Craton and the Svecofennian Orogen, is one of the major tectonic structures of the Fennoscandian Shield and hosts numerous mineral deposits and prospective ore occurrences. Investigation of the deep structure of such crustal boundary zones is essential for reconstructing the geodynamic evolution of the region and for advancing modern mineral systems research based on lithospheric architecture, fluid pathways, and the structural controls of mineralization. This paper presents the results of an integrated geophysical investigation of the Janisjarvi Fault Zone, combining a low-altitude UAV aeromagnetic surveying, passive microseismic sounding method (MSM), and the joint interpretation of data acquired along the Vyborg–Suojärvi Magnetotelluric Profile. The integrated dataset was used to construct consistent magnetic, seismic, and electrical resistivity models that characterize the crustal structure over a wide range of depths. Particular attention is paid to identifying structural heterogeneities of different scales, analyzing their spatial relationships, and assessing the potential of integrated geophysical interpretation for reconstructing the deep architecture of crustal boundary zones within the Fennoscandian Shield. The results contribute to the development of geophysical approaches for mineral systems analysis and to the identification of deep-seated structures that may control fluid migration and ore localization.