Magnetic model of the crystalline crust and heterogeneity of the lithosphere in the junction zones between the East European Craton and surrounding structures. Part I. The SW border

• Datum: 2026
• Hauptverfasser: Pashkevich, Inna, Orlyuk, Mykhailo, Bakarjieva, Mariya, Marchenko, Andriy
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: S. Subbotin Institute of Geophysics of the NAS of Ukraine 2026
• Schlagworte: East European Craton; 3Dmagnetic modelling; magnetic field; lithosphere heterogeneity; magnetic anomalies; magmatism; Teisseyre-Tornquist line; mantle; subduction zones
• Online Zugang: https://journals.uran.ua/geofizicheskiy/article/view/347053
• Назва журналу: Geofizicheskiy Zhurnal

his article is the first attempt to establish a connection between magnetic heterogeneities in the crystalline crust in the Teisseyre-Tornquist Line region of the SW edge of the East European Craton and heterogeneities in the mantle. A 3D magnetic model of the crystalline crust was created using near-surface anomalous magnetic fields, velocity and structural sections from seismic profiles. The sources are attributed to two levels: local sources to the entire thickness of the upper crust, and deep ones to the middle and lower crust. Magnetization is assumed to be homogeneous, equilibrium, and constant to the depth of the Moho discontinuity or until the Curie temperature of magnetite is reached. This model parameterization led to the estimation of the minimum possible values of source magnetization. The total effect of crustal sources was matched to the observed field by trial and error with an error of no more than 30 nT. The relationship between crustal magnetic heterogeneities and mantle structure is based on the use of compiled diagrams of the main features of the crystalline crust, of the heterogeneity of the subcrustal mantle, and the transition layer from the upper to the middle mantle. The main feature of the 3D magnetic model is the presence of deep magnetic bodies accompanying Teisseyre-Tornquist Line, the Sörgenfrey-Tornquist Zone and the Thor-Tornquist Suture. The strip of magnetic bodies from NE is limited by the lineament L subparallel Teisseyre-Tornquist Line, which we have identified based on the magnetic field structure. It correlates with the Caledonian deformation front in Fennoscandia and the Rava-Ru’ska fault in Sarmatia. This allows us to link magnetic sources with the activation of the Teisseyre-Tornquist Line system and mafic intrusions. The magmatic genesis of these magnetic sources is also evidenced by their location above the overthrust of the subcrustal mantle of the East European Craton onto the mantle of the West European Platform. The overthrust was established based on seismotomography data. It correlates with the underthrust of the lower crust of the East European Craton under the crust of the West European Platform. It is assumed that these structures are connected with their synchronous movement from the NE to the SW, the formation of a stretchingzone, and the intrusions. The stretching regime along the Teisseyre-Tornquist Line may also be caused by SW subduction, which is confirmed by the identified high-speed inclined layers (slabs).The magmatic origin of magnetic sources does not exclude the formation of ‘secondary’ magnetic minerals due to the penetration of deep fluids into the crystalline crust. This process is facilitated by the increased permeability of the lithosphere, the ‘blurring’ of the main geodynamic boundary, and the disturbance inthe transition layerstructure of the upper mantle. The nature of deep magnetic sources associated with Teisseyre-Tornquist Line can thus be explained by both primary magnetic minerals of mafic rocks and secondary minerals brought up from the depths.