FEATURES OF SEISMIC EFFECT ATTENUATION OF THE RUSSIAN PLATFORM AND URAL EARTHQUAKES

N.V. Petrova, R.A. Dyagilev, I.P. Gabsatarova

Geophysical Survey of the Russian Academy of Sciences, Obninsk, Russia

Corresponding author: N.V. Petrova, e-mail: npetrova@gsras.ru

Abstract. The article presents analysis of macroseismic effect of earthquakes occurred in the late XX and early XXI centuries at the Russian platform and the Urals. The relationships between seismic intensity I, magnitude M, and hypocentral distance r, according to the Blake–Shebalin’s equation, were established for five regions of the study area. For the first time, the coefficients of separate macroseismic field equations for the Ural near-surface and deeper sources were obtained (h ≤ 1 km: b = 1.5, v = 2.43, c = 1.01; h > 1 km: b = 1.5, v = 2.9, c = 2.13). The possibility of using the Blake–Shebalin’s equation with average coefficients (b = 1.5, v = 3.5, c = 3) was confirmed for earthquakes in the south of the Russian Platform. The low attenuation of the intensity of the Baltic Sea earthquakes is established for the Eastern Baltic territory. The coefficient v = 2.48 in the obtained equation is similar to v = 2.7 which is recommended for this territory in the new Russian and Interstate Standard «Earthquakes. Macroseismic Intensity Scale» (2019). But the level of seismic effect according to the established equation is higher than predicted with this standard. The reduced attenuation coefficients for the earthquakes in the East of the Russian Platform and induced events (h ≤ 1 km) in the eastern part of the Baltic Shield were obtained, v = 2.3 and v = 3.02 respectively. However, due to the deficiency of field data, these results need to be refined. New dependencies are recommended for more accurate prediction of the seismic effect from earthquakes in these regions.

Keywords: macroseismic scale, shaking intensity, macroseismic field equation, magnitude, attenuation

About the authors

PETROVA Nataliya Vladimirovna – Geophysical Survey of the Russian Academy of Sciences. Russia, 249035, Kaluga region, Obninsk, Lenin Av. 189. E-mail: npetrova@gsras.ru

DYAGILEV Ruslan Andreevich – Geophysical Survey of the Russian Academy of Sciences. Russia, 249035, Kaluga region, Obninsk, Lenin Av. 189. E-mail: dra@gsras.ru

GABSATAROVA Irina Petrovna – Geophysical Survey of the Russian Academy of Sciences. Russia, 249035, Kaluga region, Obninsk, Lenin Av. 189. E-mail: ira@gsras.ru

Cite this article as: Petrova N.V., Dyagilev R.A., Gabsatarova I.P. Features of seismic effect attenuation of the Russian platform and Ural earthquakes, Voprosy Inzhenernoi Seismologii (Problems of Engineering Seismology). 2020. V. 47, No. 4. P. 5–25. [in Russian]. https://doi.org/10.21455/VIS2020.4-1

English translation of the article will be published in Seismic Instruments, ISSN: 0747-9239 (Print) 1934-7871 (Online), https://link.springer.com/journal/11990