Abstract

The article presents instrumental and macroseismic data on earthquakes of the Carpathian region in 2013, felt on the territory of the Republic of Moldova. Three earthquakes, with an intermediate focal depth, occurred in the Vrancea zone: August 11 with h=93 km, КР=11.8; October 6 with h=140 km, КР=14.1; Octo-ber 15 with h=144 km, КР=12.3. Also in 2013, a swarm of small earthquakes was recorded, near Galati (Ro-mania) and Giurgiulesti (Moldova). The swarm arose September 23, its shocks were recorded for two months. More than 370 seismic events happened, of which three had КР  11 (September 29, 30, and Octo-ber 4 with КР=11.2, 10.9, 10.6). The intensity of shaking reached 5. For earthquakes, September 29, 30 and October 4 regional solutions for the focal mechanism from the Mostryukov and Petrov catalog (GO "Borok" IPE RAS) were received. The event of August 11, 2013, with КР=11.8, occurred at a depth of 93 km on the northeastern margin of the focal zone of Vrancea, felt at the epicenter with intensity I=4. In Chisinau, only some people felt weak shocks (I=2). The two largest earthquakes of 2013 occurred on October 6 at 01h 37m (КР=14.2, mb=5.3, I0=6) and on October 15 at 19h 33m (КР=12.3, mb=4.8), in the central part of the focal zone Vrancea. Between these events, three more earthquakes were noted with ML=3–3.5. However, the most extensive macroseismic manifestations arose from the main shock – October 6, which caused shaking in the territory of four states – in Romania, in the north of Bulgaria, in the south-west of Ukraine, and in Moldova. The reason for such a significant spread of tremors lies in a large focal depth of 140 km. But for the same reason, the intensity of the macroseismic impact did not exceed I=5 in Romania and I=4–5 in Moldova and Ukraine. As a result, a map of the intensity distribution of the October 6 earthquake is given, built on the basis of data processing in 104 locations. Various solutions for the focal mechanisms of intermediate earthquakes in 2013 are presented. The consistent manifestation of a swarm of crustal earthquakes and a number of earthquakes of intermediate depth confirms the unity of tectonic processes in the Carpathian region. The accumulated seismic stresses were preliminarily realized in the form of crustal shocks, then powerful discharge occurred in the Vrancea region, which interrupted a series of events associated with Sfintul-Gheorghe and Peceneaga–Camena faults.

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