Analysis of the seismicity of the Vrancea area for 2014-2023 and its manifestation on the territory of the Republic of Moldova

The main seismic hazard of the Carpathian region is due to the regular action of intermediate depth foci in the Vrancea region. The article examines the main features of the seismicity of the focal area for the ten-year period from 2014 to 2023, including 20 earthquakes in the Vrancea region, fluctuations from which were felt on the territory of the Republic of Moldova, special attention is paid to the strongest earthquakes. Data on the republic were collected for seven earthquakes, and isoseismal maps were built on their basis. The intensity of the earthquakes was determined on the scale of MSK-64. The most severe macroseismic impact is in the southwestern part of the country, which, according to the seismic zoning map, belongs to the 8-grade zone. An analysis of the features of the seismic process in the Carpathian region showed that the value of the observed magnitudes of intermediate earthquakes did not exceed the value M = 5.7, and the maximum intensity in the epicenter I = 6. In the territory of the Republic of Moldova, the intensity did not exceed I=4-5. In 2014-2016, an intensification of the seismic process was observed. The study of the mechanism of the earthquake source in the Vrancea region shows that this zone is influenced by the forces of sub-horizontal compression and sub-vertical stretching. Thrust movements prevail in the foci. Compression is directed across the strike of tectonic structures. The magnitude of the crustal earthquakes in the Ramnicul-Sarat area was the largest during the period of instrumental observations. The study of the impact of crustal and subcortical earthquakes will contribute to the elaboration of the normative map of seismic zoning of Moldova.