Izumo region - Izumochiho

...Volcanoes with lava domes, such as Mt. Sanbe in the northeast of the plateau and Mt. Aono in the southwest, can be seen, and hot springs are widely distributed. Small basins have developed in the mountainous areas, and in the mountainous areas of the Izumo region in particular, modern iron sand mining sites have left distinctive topography on basins and terraces. The Oki Islands consist of Dogo, which is based on Oki gneiss, said to be the oldest rock in Japan, and Dozen, whose central crater cone is Mt. Takuhi, and whose caldera crater floor is an inland sea surrounded by the islands of Nishinoshima, Nakanoshima, and Chiburi. ...

*Some of the terminology that refers to the "Izumo region" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…高原北東部に三瓶（さんべ）山，南西部に青野山などの溶岩円頂丘をもつ火山が見られ，温泉の分布は広い。山間部には小盆地が発達し，とくに出雲地方の山間部には近世の砂鉄採取地が，盆地，段丘上に特有の地形を残す。隠岐諸島は日本最古の岩石ともいわれる隠岐片麻岩を基盤とする島後（どうご）と，焼火（たくひ）山を中央火口丘とし，西ノ島，中ノ島，知夫里（ちぶり）島に囲まれた内海をカルデラ火口原とする島前（どうぜん）からなる。…

※「出雲地方」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