(1) (a) (b) (c) (d) 1) 2) 3) 4) 5) 6) 7) 8) (e) (2) (a) (b) 1) (c) (d) (e) (f) (3) 131
(1) (a) 2.2.2 (b) (c) (d) 1) 6 2) 6 3) 6 132
4) 1 3 5 6 6) 1 6 7) 1 6 8 1 3 (e) 6 (2) (a) 133
(1) 27 26 8 27 8 6 27 26 GPS 28 27 8 P (b) 1) 3 3 6 1) 65 mm 36 5 mm 1 SD 1 2,3,4,5,6) 25 1 27 26 8 1 1 27 8 3 ( 1) 3 27 8 1 134
6 ( 2 2) 26 25 1 2 27 8 12 1 58 28 3 2 JS156 27 8 12 WIN 7) 26 27 69 3 8) 1 5349 9) 4 P 5 1) 6 (c) 27 6 28 6 27 (d) 1) : 2 61, S55-S68, 29. 135
2) Hirata, N., Tokuyama, H., Chung, T.W.: An anomalously thick layering of the crust of the Yamato Basin, southeastern Sea of Japan: the final stage of back-arc spreading, Tectonophysics 165, 33-314, 1989. 3) Kurashimo, E., Shinohara, M., Suyehiro, K., Kasahara, J., Hirata, N.: Seismic evidence for stretched continental crust fragment in the Japan Sea, Geophysical Research Letters 23, 367-37, 1996. 4) Nakahigashi, K., Shinohara, M., Yamada, T., Uehira,K., Mochizuki, K., Kanazawa, T.: Seismic structure of the extended continental crust in the Yamato Basin, Japan Sea, from ocean bottom seismometer survey, Journal of Asian Earth Sciences, 67-68, 199-26, 213. 5) Sato, T., Takahashi, N., Miura, S., Fujie, G., Kang, D.-H., Kodaira, S., Kaneda, Y.: Last stage of the Japan Sea backarc opening deduced from the seismic velocity structure using wide-angle data, Geochemistry, Geophysics, Geosystems 7, Q64. http://dx.doi.org/1.129/25gc1135, 26. 6) Shinohara, M., Hirata, N., Nambu, H., Suyehiro, K., Kanazawa, T., Kinoshita, H.: Detailed crustal structure of northern Yamato Basin, Proceedings of the Ocean Drilling Program Scientific Results 127/128 Pt.2, 175-116, 1992. 7) win - 1 C22-P18, 1992. 8) Nakahigashi, K., Yamada, T., Uehira, K., Sakai, S., Mochizuki, K., Shiobara, H., Kanazawa, T.: Deep slab dehydration and large-scale upwelling flow in the upper mantle beneath the Japan Sea, Journal of Geophysical Research, Solid Earth, 12, doi:1.12/214jb11781, 215. 9) Zhao, D., A. Hasegawa, and S. Horiuchi, Tomographic imaging of P and S wave velocity structure beneath northeastern Japan, J. Geophys. Res., 97, 19,99-19,928, 1992. 1) Yoshizawa K., Miyake, K., Yomogida, K., 3D upper mantle structure beneath Japan and its surrounding region from inter-station dispersion measurements of surface wacves, Physics of the Earth and Planetary Interiors, 183, 4-19, 21. 11) Kennett, B. L. N. and E. R. Engdahl, Traveltimes for global earthquake location and phase identification, Geophys. J. Int. 15 (2) 429-465, 1991. (e) K. Nakahigashi, M. Shinohara, T. Yamada, Mantle wedge heterogeneous structure beneath the Japan Sea revealed by long-term seafloor seismic observations International Union of Geodesy and Geophysics 215 General Assembly 27 6 28 136
K. Uehira, S. Sakai, K. Mochizuki, H. Shiobara, T. Kanazawa K. Repeating long-term ocean 215 American 27 Nakahigashi, bottom seismic observations Geophysical Union Fall 12 14 T. Yamada, in the southern part of Japan meeting Y.Yamashita, Sea K.Mochizuki, H.Shiobara, M.Shinohara (f) 1) 2) 3) (3) 137
1 26 - (JST) (m) (JST) JS141 1Hz 214/8/2-3:18:3 38-17.4 135-34.99 2,98 78 214/8/2-12:: JS147 214/8/2-8:33:2 37-41.74 135-48.41 2,814 557 214/8/2-18:: JS143 214/8/2-14:23:25 37-54.88 134-37.49 2,968 558 214/8/2-18:: JS144 214/8/2-19:55:45 37-19.98 134-45.61 2,686 556 214/8/3-:: JS145 1Hz 214/8/3-:28:4 36-59.92 134-5.97 1,962 676 214/8/3-6:: JS146 1Hz 214/8/3-6:17:52 36-41.27 134-55.9 1,751 653 214/8/3-12:: (JST) 215/1/1-:: 215/1/1-:: 215/1/1-:: 215/1/1-:: 215/1/1-:: 215/1/1-:: 138
2 27 - (JST) (m) (JST) JS151 1Hz 215/8/11-4:22:13 38-17.4 135-35. 2,98 684 215/8/11-7:3: JS157 215/8/1-21:12:3 37-41.73 135-48.41 2,81 554 215/8/11-1:: JS153 215/8/11-1:47:14 37-54.77 134-37.22 2,97 555 215/8/11-14:: JS154 215/8/11-15:28:14 37-19.99 134-45.59 2,69 553 215/8/11-18:3: JS155 1Hz 215/8/11-2:14:29 36-59.99 134-5.99 1,96 717 215/8/11-23:: JS156 1Hz 215/8/12-1:7:15 36-41.29 134-55.4 1,75 663 215/8/12-1:58: (JST) 216/1/1-:: 216/1/1-:: 216/1/1-:: 216/1/1-:: 216/1/1-:: 216/1/1-:: 139
1 27 8 2 27 8 14
1 2 25 7 26 25 26 141
2 27 26 142
3 69 (M > 2.5) 518 143
4 29 144
5 P iasp91 11) 145
6 146