Problems of Engineering Seismology: article

Morphotectonics of the Imandra-Kolvitsky Fault and parameters of the focal zone of paleoearthquakes in the Luvenga Tundra (Kola Peninsula)
S.V. Shvarev 1,2 S.B. Nikolaeva 3 I.V. Bondar 2,1 A.O. Koroleva 2,1 A.O. Komarov 4
1 Institute of Geography of the Russian Academy of Sciences 2 Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences 3 Geological Institute of the Kola Scientific Center of the Russian Academy of Sciences 4 Institute of Architectural and Construction Design, Geotechnics and Reconstruction LLC
Journal: Problems of Engineering Seismology
Tome: 51
Number: 2
Year: 2024
Pages: 74-101
UDK: 551.248.2+551.4+551.24.03
DOI: 10.21455/VIS2024.2-5
Keywords: seismic fault, morpholineaments, paleoearthquakes, seismic deformations, epicenter zone, late Pleistocene, Holocene, Eastern Fennoscandia
Аnnotation: Detailed paleoseismogeological studies have been carried out in the area of the Kandalaksha low-mountain massifs on the Kola Peninsula (northeast of the Fennoscandian Shield). In order to identify traces of paleoearthquakes, parametrization and dating of events, a set of methods was used, including analysis of satellite images and digital elevation models (DEM), ground-based geological and geomorphological mapping, structural and tectonophysical studies, drilling of lakes in fault zones, selection of paleosols and their dating by radiocarbon method (14C). The study of various groups of seismic disturbances in topography and rock massifs (seismotectonic, seismogravitational, seismovibrational), as well as morphotectonic data, allowed us to identify a large Imandro-Kolvitsky seismotectonic zone extending over 100 km in the southwest of the Kola Peninsula. As a result of the research, it was found that the zone inherited from the Precambrian showed activation in the Late Glacial and Holocene. The identified areas of seismic deformations, surveyed in the area of the Luvenga Tundra key site, allowed us to establish that there was epicenter zone of seismic fault, the intensity of which ranged from IX to VIII points in Late Glacial with a decrease in the Holocene. The seismic fault has a dextral strike-slip kinematics with a thrust component, implemented in the stress field of the meridional (NNE) maximum compression and wide-latitude (WNW) stretching. New data on the assessment of the age of paleoearthquakes indicate the 4 most likely events in the Holocene (cal. kyr. BP): 1) ≈ 10.4; 2) ≈ 7.5; 3) ≈ 2.8–3.0; 4) ≈ 0.38. The conducted research can be used to develop scientific and methodological foundations for assessing the risks of catastrophic processes, updating earthquake catalogs and databases on active faults, as well as preventing seismic hazards of platform territories.