About Macroseismic Displays of Yandary Earthquake, October 17, 2018

Abstract

The article analyzes and presents the data on the earthquake on October 17 at 15h55m GMT, which occurred on the outskirts of the village of Yandare of the Republic of Ingushetia. Intensity of the shok equaled 5 in the epicenter. According to instrumental data of networks of seismic stations NOGSR, OBGSR, DAGSR the following solution of parameters of an earthquake is received: φ=43,27°N, λ=44,92°E, h=12 km, KР=11,5. The history of seismicity of the focal zone of the investigated earthquake for the last 150 years is studied. The earthquake is confined to the active Sunzha fault. The forshock activity and a few series of aftershocks are considered. For the earthquake, the mechanism of the focus was calculated according to the signs of the first arrivals of longitudinal P-waves at 48 stations well surrounding the epicenter and located at distances Δ = 0,3‑50,5° km. According to the received decision, the earthquake appeared under the influence of prevailing compression stresses, the type of movement – the reverse fault. For collecting macroseismic data departure in an epicentralny zone and nearby areas was carried out. Evaluation of intensity was carried out on the basis of theSeismic intensity scale (SHSI-17). The earthquake with an intensity of 5 points was manifested in the settlements of Yandare, Troitskoye, Karabulak. Fluctuations were felt in Sunzha, Barsuki and Plievo force 4 points, Nazran – 3‑4 points. In the settlements of Magas, Ali-Yurt, Middle Achaluki, the sensitivity of the earthquake was 3 points. In seven settlements, the fluctuations showed an intensity of 2 points. In Vladikavkaz earthquake was felt on the upper floors of multi-storey buildings. Data on the manifestations of the Yandaryearthquake are interesting from the point of view of the analysis of the distribution of the intensity of concussions, the study of the seismicity of the region as a whole, as well as the connection with the geological structure of the territory.