aist AIST gsjGSJ   
Quaternary Volcano > Active Volcanoes > Aogashima
Aogashima Volcano   textgeologicmap3Dgeologicmap

   SiO2 contents of rocks of Aogashima are within the range of 49-63 %. However, they are mostly tholeiitic basalt ( zoom Table 1 ) . Aogashima Volcano is composed of several small stratovolcanoes with multiple craters. The chemical compositions are slightly different from one crater to the other ( Takeda et al., 1992 ). Kurosaki Volcano consists of olivine basalt, clinopyroxene-olivine basalt, and clinopyroxene-orthopyroxene andesite. Main part of stratovolcano consists of olivine basalt and clinopyroxene-bearing olivine basalt. Little amount of clinopyroxene-orthopyroxene andesite lava is distributed in addition. Essential materials of aphyric basalt and Ojiroike surge deposits consist of almost identical rocks. Kintagaura lava and Yasundogo fall deposits are made up with olivine basalt, and clino- and ortho-pyroxene andesite. Lavas of Tenmei eruption are clinopyroxene-orthopyroxene-bearing aphyric andesite.

   prev PREV   next NEXT