Earthquake of February 3, 2016 in the Middle Baikal Region: Source Parameters and Macroseismic Effects.

Radziminovich, Ya. B.; Filippova, A. I.; Gileva, N. A.; Melnikova, V. I.

We study in detail the source parameters, seismotectonic position, and macroseismic effects of the February 3, 2016, earthquake that occurred in the Middle Baikal region. This earthquake is one of the relatively few instrumentally recorded seismic events in the northern part of the South Baikal basin that has occurred in a previously low-active region. The main source parameters of the earthquake are calculated from the joint inversion of the amplitude spectra of surface waves and polarities of the first arrivals of P-waves: scalar seismic moment (M0 = 1.60 × 1016 N m), moment magnitude (Mw = 4.8), source depth (h = 22 km), and a focal mechanism (which is an almost pure normal fault). The obtained focal mechanism corresponds to the general geodynamic situation in the region of the Middle Baikal. The earthquake caused perceptible shaking over a large area, while shaking intensity of IV MSK-64 was observed at distances up to 360 km. Macroseismic data were collected by mailing questionnaires to the administrations of settlements, as well as using an online survey of the population of the southern Baikal region. The results are of interest in carrying out work to clarify the seismic hazard of the territory of the southern Baikal region.

EARTHQUAKES; EARTHQUAKE intensity; DEMOGRAPHIC surveys; INTERNET surveys; SURFACE fault ruptures

Izvestiya, Atmospheric & Oceanic Physics, 2022, Vol 58, Issue 8, p936

0001-4338

Academic Journal

10.1134/S0001433822080035