Open AccessShear‐wave polarization anisotropy beneath the north‐eastern part of Honshu, Japan
Author(s) -
Okada Tomomi,
Matsuzawa Toru,
Hasegawa Akira
Publication year - 1995
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1995.tb06890.x
Subject(s) - geology , shear wave splitting , seismology , anisotropy , shear (geology) , slab , perpendicular , shear waves , polarization (electrochemistry) , geophysics , mantle wedge , seismic anisotropy , mantle (geology) , lithosphere , tectonics , petrology , optics , geometry , physics , chemistry , mathematics
SUMMARY We have investigated the shear‐wave polarization anisotropy in the north‐eastern Japan arc by using waveforms from many local earthquakes at various depths. We used a cross‐correlation method to detect the shear‐wave splitting. For intermediate‐depth and deep events, the observed fast shear‐wave oscillation directions (FSODs) are oriented parallel to the dip direction of the slab at the western stations, while they are oriented perpendicular to the dip direction at the eastern stations. These observations indicate that significant anisotropy exists in the mantle wedge, and that its nature is quite different between the eastern and the western parts.