[SSS04-P49] Sub-slab anisotropy in the western Pacific :
The Izu-Bonin and Mariana regions
We measured source-side shear wave splitting with receiver-side correction for the Izu-Bonin and Mariana subduction zones. The initial results show that the deeper slab is associated with larger delay times (dt) in Izu-Bonin region, while delay times of deeper slab in the Mariana are smaller. The fast directions (f) of the two regions seem to be random with respect to the slab contour. However, anisotropy for shallow events in the Izu-Bonin slab is consistent with the relative plate motion. The next step is to consider the radial anisotropy in the receiver-side correction.