1. Department of Geology, State University of Gorontalo, Kota Gorontalo, Indonesia
2. The Research Institute for Humanity and Nature (RIHN), Kita-ku, Kyoto, Japan
3. Graduate School of Sciences and Engineering, Ehime University, Matsuyama, Japan
4. Tsuneishi Shipbuilding Co., Ltd. Fukuyama, Japan
5. Department of Physics, State University of Gorontalo, Kota Gorontalo, Indonesia
6. Department of Educational Geography, University of Gorontalo, Kota Gorontalo, Indonesia
7. Cyclotron Research Center, Iwate Medical University, Takizawa, Japan