1. Department of Geoscience; Faculty of Education; Saitama University; Shimo-Okubo 255 Sakura-Ku Saitama City 338-8570 Japan
2. Division of Natural Sciences; The United Graduate School of Education; Tokyo Gakugei University; Tokyo Japan
3. Department of Geosciences; National Taiwan University; Taipei 106 Taiwan
4. Institute of Earth Sciences; Academia Sinica; Taipei 115 Taiwan
5. Department of Geoscience; Shimane University; Matsue City 690-8504 Japan