Geophysical research: article

V.A. Kulikov 1 Yu.A. Morozov 2 A.P. Ionicheva 3 N.M. Shagarova 1 A.G. Yakovlev 1 E.Yu. Sokolova 2 M.A. Matveev 2 E.N. Terekhov 2,4
1 Lomonosov Moscow State University 2 Schmidt Institute of Physics of the Earth, Russian Academy of Sciences 3 Geoelectromagnetic Research Center, IFE RAS 4 Geological Institute of the Russian Academy of Sciences
Journal: Geophysical research
Tome: 24
Number: 4
Year: 2023
Pages: 58-80
UDK: 550.370; 550.379; 550.389.1;551.242; 551.243
DOI: 10.21455/gr2023.4-4
Full text
Keywords: audio-magnetotelluric sounding, magnetic survey, geoelectric model, electrical resistivity, two-dimensional inver-sion, basement–cover system, skin tectonics.
Аnnotation: The article presents the methodology and results of electromagnetic soundings of the Meyer thrust zone of Northern Ladoga region, which separates volcano-terrigenous Paleoproterozoic cover complexes of different metamorphism intensity. Obtained in the course of detailed geological mapping ideas about the structural and material features of the studied fold-thrust forms of this zone were supplemented by depth characteristics and visualization of the latter in the “Paleoproterozoic cover–Archean basement” system. Thanks to the adequate choice of the audio-magnetotelluric sounding method as a basic one in combi-nation with magnetic survey, meaningful geoelectric images of the fold-thrust structures down to a depth of 1 km were identified. Elements of both “thick-skinned” and “thin-skinned” tectonics, with joint and autonomous deformations of basement and cover complexes, were traced in the constructed electrical conductivity sections. A new dome-shaped structure of the Archean basement, inscribed in the linear series of small protrusions of the Archean basement of the Sortavala Group, was distinguished.
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