1. Graduate School of ScienceTohoku University Sendai Japan
2. V.S. Sobolev Institute of Geology and Mineralogy, Siberian BranchRussian Academy of Sciences Novosibirsk Russia
3. Now at Geophysical LaboratoryCarnegie Institution of Washington Washington Dis. of Columbia USA
4. Earthquake Research InstituteUniversity of Tokyo Tokyo Japan
5. Materials Dynamics Laboratory, RIKEN SPring‐8 CenterRIKEN Sayo Japan
6. Graduate School of Material ScienceUniversity of Hyogo Hyogo Japan
7. Graduate School of ScienceKobe University Kobe Japan
8. Research and Utilization DivisionSPring‐8/JASRI Sayo Japan