About YASUI MAYA
About Gunma prefecture
About Nagano prefecture
About crater(volcano)
About geologic time
About geological history
About sedimentation(accumulate)
About pumice
About absolute age
About radiocarbon dating
About pyroclastic flow
About volcanostratigraphy
About archives
About geologic map
About pyroclastic fall deposit
About 14C Age
About Plinian eruption
About vulcanian eruption
About Asama volcano
About sedimentary age
About isopach map
About eruption age
About eruption history
About Volcanic geology in general
About 火山
About 噴火
About 履歴
About 復元
About 手がかり
About 軽石