@article{oai:kanazawa-u.repo.nii.ac.jp:00011096,
 author = {平松, 良浩 and 水上, 知行 and Terada, Tadashi and Hiramatsu, Yoshihiro and Mizukami, Tomoyuki},
 issue = {8},
 journal = {Journal of Geophysical Research B: Solid Earth},
 month = {Jan},
 note = {Shear wave splitting from local intermediate-depth earthquakes is investigated to detect the anisotropic structure in the mantle wedge beneath the South Kyushu area, Japan. We observed shear wave splitting with NEE-SWW to NWW-SEE polarization directions and delay times of 0.04-0.63 s. Trench-normal shear wave polarization anisotropy with a delay time greater than 0.3 s probably overlaps in the high VP/VS region at a depth of 100-150 km beneath the volcanic front. Model calculations for the cause of the anisotropy suggest that the development of "C-type" olivine crystallographic preferred orientation (CPO) with a trench-parallel b axis concentration and a trench-normal a axis concentration best reproduces observations compared to A-, B-, or E-type olivine CPOs and antigorite CPO. We conclude that a thick anisotropic layer, approximately 50 km, is formed by concentration of interstitial fluid in peridotite. We briefly discuss the mechanism carrying water to the deep mantle wedge. A possible explanation is that interstitial fluids in the mantle wedge are effectively released because of a decrease in dihedral angles of olivine-fluid interfaces at 150 km depth. Our results imply a close relation between the high density of explosive volcanoes in the South Kyushu area and the underlying water-rich mantle. © 2013. American Geophysical Union. All Rights Reserved.},
 pages = {4253--4264},
 title = {Shear wave anisotropy beneath the volcanic front in South Kyushu area, Japan: Development of C-type olivine CPO under H2O-rich conditions},
 volume = {118},
 year = {2013}
}