Affiliation: | aResearch Institute of Natural Sciences, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan bDepartment of Natural and Environmental Science, Kochi University, Akebono-cho 2-5-1, Kochi 780-8520, Japan cDepartment of Earth Science Education, Kyungpook National University, Daegu, Kyungsangbuk Do, 702-701, South Korea |