Open AccessMUYAKAN-II EARTHQUAKE on MAY 23, 2014 with КР=14.3, Mw=5.5, I0=7–8 (Northern Baikal region)
Author(s) -
Н. А. Гилева,
В. И. Мельникова,
А. И. Середкина,
Ya. B. Radziminovich
Publication year - 2020
Publication title -
zemletrâseniâ severnoj evrazii v ... godu
Language(s) - English
Resource type - Journals
ISSN - 1818-6254
DOI - 10.35540/1818-6254.2020.23.33
Subject(s) - aftershock , seismology , geology , foreshock , seismic moment , rift , moment tensor , magnitude (astronomy) , moment magnitude scale , seismic hazard , tectonics , deformation (meteorology) , geometry , physics , fault (geology) , oceanography , mathematics , astronomy , scaling
We consider the May 23, 2014 Muyakan earthquake (Mw=5.5) occurred in the Muyakan Range at the north-east of the Baikal rift zone near the eastern tunnel portal of the Baikal-Amur Mainline. This event was followed by numerous aftershocks (КР=5.6–9.9) which number exceeded 2000 by the end of the year. Spatio-temporal analysis of the Muyakan seismic sequence shows that its epicentral field consists of two isolated clusters: eastern and western ones. All the main events including the foreshocks, main shock and the strongest aftershocks (Mw=4.4; 4.5) occurred in the eastern cluster while only small seismic events (КР<10.0) were recorded in the western one. Seismic moment tensor was calculated for the Muyakan earthquake from surface wave amplitude spectra. As a result, we obtained information about the rift type focal mechanism, scalar seismic moment (M0=1.9•1017 Nm), moment magnitude (Mw=5.5) and hypocentral depth (h=24 km). From regional data, hypocentral depths of the main shock and the major number of the following earthquakes (80 %) were distributed in the depth range h=3–11 km. Maximum intensity of the main shock (4–5 according to MSK-64) was felt in Severomuysk urban village (=29 km). The obtained results could be used for seismic hazard assessment of the crucial part of the Baikal-Amur Mainline.