Splitting of ScS and S waves from the M^sub w^ 8.4 Okhotsk deep-focus earthquake (May 24, 2013) and its strong aftershocks

• Published in: Russian journal of Pacific geology 2014-11, Vol.8 (6), p.456
• Main Authors: Luneva, M N, Pupatenko, V V
• Format: Article
• Language: English
• Subjects: Aftershocks; Earthquakes; Plate tectonics; Seismic activity; Seismology
• ISSN: 1819-7140; 1819-7159
• DOI: 10.1134/S1819714014060050

The parameters of split shear ScS and S waves from the strongest (M ^sub w^ = 8.4) Okhotsk earthquake and its strong aftershocks that occurred in the mantle's transitional zone in the backarc part of the Kamchatka subduction zone are measured. The measurement results show domination of the fast ScS wave's east azimuths (110°-149°), which are orthogonal to the trench orientation, and the time difference between the arrivals of the ScS waves (δt) in the range of 0.9-1.6 s. The fast S wave from the Okhotsk earthquake is east-directed (89°), and the time difference between its arrivals is up to 2.5 s. As for aftershocks, the azimuths of the fast S waves are oriented in parallel to the trench, and δt are estimated at 1.2-1.3 s. The orientations of the azimuths for the ScS and S waves are consistent with the model of the transverse-isotropic symmetry of the medium with the symmetry axis tilted along the plate dip and/or along the trench strike.[PUBLICATION ABSTRACT]