is a stratovolcano complex in the

Ōu Mountains The are a mountain range in the Tōhoku region of Honshū, Japan. The range is the longest range in Japan and stretches south from the Natsudomari Peninsula of Aomori Prefecture to the Nasu volcanoes at the northern boundary of the Kantō ...

of western Iwate Prefecture, in the

Tōhoku region The , Northeast region, or consists of the northeastern portion of Honshu, the largest island of Japan. This traditional region consists of six prefectures (''ken''): Akita, Aomori, Fukushima, Iwate, Miyagi, and Yamagata. Tōhoku reta ...

of northern Honshū, Japan. With an elevation of , it is the highest in Iwate Prefecture. It is included as one of the 100 famous mountains in Japan, a book composed in 1964 by

mountaineer Mountaineering or alpinism, is a set of outdoor activities that involves ascending tall mountains. Mountaineering-related activities include traditional outdoor climbing, skiing, and traversing via ferratas. Indoor climbing, sport climbing, an ...

and author

Kyūya Fukada was a Japanese writer and mountaineer active during the Shōwa period in Japan. Early life Kyūya was born in what is now Kaga city, Ishikawa prefecture. He attended the Fujishima High School, followed by the preparatory school for the Tokyo I ...

.Hyakumeizan, Hiking Japan!
. Japan Gazetteer. Accessed June 27, 2008. The mountain is on the borders of the municipalities of Hachimantai, Takizawa, and

Shizukuishi is a town located in Iwate Prefecture, Japan. , the town had an estimated population of 16,263 in 6354 households, and a population density of 27 persons per km². The total area of the town is . Geography Shizukuishi is located in the Ōu M ...

, west of the prefectural capital of

Morioka is the capital city of Iwate Prefecture located in the Tōhoku region of northern Japan. On 1 February 2021, the city had an estimated population of 290,700 in 132,719 households, and a population density of . The total area of the city is . G ...

. Much of the mountain is within the borders of the

Towada-Hachimantai National Park is a national park comprising two separate areas of Aomori Prefecture, Aomori, Iwate Prefecture, Iwate, and Akita Prefecture, Akita Prefectures of Japan, Prefectures, Japan. The Towada-Hakkōda area encompasses Lake Towada, Hakkōda Mountains, ...

. The mountain is also referred to as the "Nanbu Fuji" for its resemblance to Mount Fuji.

Geology

Mount Iwate consists of a younger eastern symmetrical stratovolcano (Higashi-Iwate, "East Iwate") overlapping an older western stratovolcano (Nishi-Iwate, "West Iwate") which has collapsed to form a caldera. Nishi-Iwate was formed approximately 700,000 years ago, and forms two-thirds of the mountain body. Higashi-Iwate was a later (300,000 years ago) parasitic volcano, which now forms the summit of the mountain. The oval-shaped, 1.8 x 3 km caldera of Nishi-Iwate has a 0.5 km wide crater, partially filled by a

crater lake Crater Lake ( Klamath: ''Giiwas'') is a volcanic crater lake in south-central Oregon in the western United States. It is the main feature of Crater Lake National Park and is famous for its deep blue color and water clarity. The lake partly fill ...

called Lake Onawashiro. Several

somma A somma volcano (also known as a sommian) is a volcanic caldera that has been partially filled by a new central cone. The name comes from Mount Somma, a stratovolcano in southern Italy with a summit caldera in which the upper cone of Mount Ves ...

including Yakushidake, the largest, surround the more recent Higashi Iwate crater rim. During the historical period, Mount Iwate erupted in 1686-1687 with a

pyroclastic surge A pyroclastic surge is a fluidised mass of turbulent gas and rock fragments that is ejected during some volcanic eruptions. It is similar to a pyroclastic flow but it has a lower density or contains a much higher ratio of gas to rock, which makes ...

; however, the eruption of 1732 was much larger and resulted in a substantial lava flow on the northeast slopes of the mountain. This four-kilometre long lava flow ("Yakebashiri Lava Flow") has been designated a

Natural Monument A natural monument is a natural or natural/cultural feature of outstanding or unique value because of its inherent rarity, representative of aesthetic qualities or cultural significance. Under World Commission on Protected Areas guidelines, na ...

by the Japanese government. Mount Iwate has largely been quiet since 1732, with a small emission of steam and ash in 1919 and a series of volcanic earthquakes from 1998 to 2003.

References

External links

* - Japan Meteorological Agency
Iwate Volcano
- Geological Survey of Japan
Iwatesan
- Smithsonian Institution: Global Volcanism Program
- Hiking in Japan, Mount IwateIwate Prefectural Tourism siteHachimantai city tourism site
{{DEFAULTSORT:Iwate Volcanoes of Honshū Stratovolcanoes of Japan Mountains of Iwate Prefecture Volcanoes of Iwate Prefecture Hachimantai, Iwate Takizawa, Iwate Shizukuishi, Iwate Highest points of Japanese national parks Pleistocene stratovolcanoes Holocene stratovolcanoes

Geology

See also

References

External links