1. Agricultural University of Athens; Mineral Resources and Agricultural Engineering; Iera Odos Str. 75 11855 Athens Greece
2. Department of Natural Resources and Environmental Studies; National Dong Hwa University; Shoufeng Hualien 97401 Taiwan
3. Department of Geological Sciences; Stanford University; Stanford CA 94305-2115 USA
4. Department of Geosciences; National Taiwan University; Taipei 10617 Taiwan
5. Institute of Earth Sciences; Academia Sinica; Nankang Taipei 11529 Taiwan