Asama Daimyojin Shrine

...A polytectonic active volcano that straddles Kitasaku District, Nagano Prefecture and Agatsuma District, Gunma Prefecture. It is 2,560 meters above sea level. It borders the Eboshi-dake volcanic group across the Kurumazaka Pass to the west, but has wide foothills to the south and north. Its growth history is complex. First, the stratovolcano Kurofu, which is similar to Mount Fuji, created a cone-shaped mountain with a height of 2,000 meters, and then a large explosion collapsed the eastern half, forming the Yunohira crater. About 20,000 years ago, an eruption began on the east side of the Kurofu crater, forming a flat mountain body (Hotokeiwa volcano) with lava flows. 11,000 years ago, there was a large eruption at Hotokeiwa volcano, spewing pumice and volcanic ash that spread to the southern and northern foothills as pyroclastic flows. ...

*Some of the terminology that refers to "Asama Daimyojin" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…長野県北佐久郡と群馬県吾妻郡にまたがる複式活火山。標高2560m。西は車坂峠をへだてて烏帽子岳火山群に接するが，南と北には広く裾野をひく。その成長史は複雑である。最初富士山型の成層火山黒斑（くろふ）火山が比高2000mの円錐形の山体をつくった後，大爆発により東半分が崩壊し，湯の平火口を生じた。約2万年前に黒斑火山の火口の東側で噴火が始まり溶岩流の扁平な山体(仏岩火山)ができた。1万1000年前，仏岩火山で大噴火があり，軽石と火山灰を噴き上げ火砕流として南･北裾野に広がった。…

※「浅間大明神」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報