STRUCTURAL CHARACTERISTICS OF THE EXTREME NORTHERN SEGMENT OF THE KOLA PENINSULA (SREDNY AND RYBACHY PENINSULAS) BASED ON A SET OF GEOLOGICAL AND GEOPHYSICAL DATA

Based on the analysis, comparison, and interpretation of a set of geological and geophysical data, including the results of borehole drilling, seismic exploration, electromagnetic (EMT) and audio-magnetotelluric (AMT) soundings, the authors have estimated the thickness distribution of the Upper Proterozoic cover within the pericratonic region of the East European Platform (Sredniy Peninsula) and the Timan-Varanger Belt of the Baikalides (Rybachy Peninsula). They have illustrated differences in the structure of these geostructural-formational blocks, reflected not only in the rock bedding conditions and the parameters of the wellbore sections, but also in the wave field and, according to EMS data, in characteristic changes in the graphs of the effective resistivity versus effective depth. On the Sredny Peninsula, EMS graphs show that the crystalline basement rocks have significantly higher resistivity than on the Rybachy Peninsula. The complex seismic pattern in the section within the latter suggests a significant influence of gently sloping fault zones on the wave field. For the first time, based on a consolidated geological and geophysical section across the peninsula, the authors have demonstrated the presence of structural-deformational heterogeneities of the cover in the form of scaly folding on the Rybachy Peninsula, reflected both in the regional seismic and in the AMTS geoelectric section.

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