Heterogeneities of the Short-Period S-Wave Attenuation Field in the Lithosphere of SouthWestern Japan


Kopnichev Y.F. Sokolova I.N.
December 2021Pleiades journals

Izvestiya - Atmospheric and Ocean Physics
2021#57Issue 111414 - 1421 pp.

Abstract—: The article considers the characteristics of the short-period S-wave attenuation field in the lithosphere of Southwestern Japan. Records of local shallow earthquakes, obtained by station MAJO at distances of ~250–900 km, were processed. We used a method that analyzes the ratio of the maximum amplitudes of Sn- and Pn-waves (Sn/Pn parameter). The dependence of this parameter on distance was plotted. We compared this dependence with analogous dependences, obtained earlier in Northeastern Japan and in the rupture zone of the great Maule earthquake (Central Chile, February 27, 2010, Mw = 8.8). The reasons for the substantial differences of these dependences in different regions are discussed. The study considers the correlation of the Sn/Pn parameter values, recorded near the rupture zones of large earthquakes in Southwestern Japan (Mw ≥ 7.0) with the passage of time after the corresponding events. Particular attention is paid to the apportionment of high attenuation zones in areas where large earthquakes that have occurred since 1900 are not known. By analogy with earlier data, it is suggested that preparation for a large seismic event can occur in such a zone.

attenuation , deep-seated fluids , large earthquakes , Sn-waves , Southwestern Japan

Text of the article Перейти на текст статьи

Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russian Federation
Institute of Geophysical Research, National Nuclear Center, Ministry of Energy of the Republic of Kazakhstan, Kurchatov, Kazakhstan

Schmidt Institute of Physics of the Earth
Institute of Geophysical Research

10 лет помогаем публиковать статьи Международный издатель

Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026