is a

stratovolcano A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with ...

complex in the

Ōu Mountains The are a mountain range in the Tōhoku region of Honshū, Japan. It 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 region. T ...

of western

Iwate Prefecture is a Prefectures of Japan, prefecture of Japan located in the Tōhoku region of Honshu. It is the second-largest Japanese prefecture (behind Hokkaido) at , with a population of 1,165,886 (as of July 1, 2023). Iwate Prefecture borders Aomori Pre ...

, 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 (): Akita, Aomori, Fukushima, Iwate, Miyagi, and Yamagata. Tōhoku retains ...

of northern

Honshū , historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the seventh-largest island in the world, and the second-most populous after the Indonesian ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

. With an elevation of , it is the highest in

. It is included as one of the

100 famous mountains in Japan is a book written in 1964 by mountaineer and author Kyūya Fukada.Hyakumeizan, Hiking Japan!
. Japan ...

, a book composed in 1964 by

mountaineer Mountaineering, mountain climbing, or alpinism is a set of outdoor activities that involves ascending mountains. Mountaineering-related activities include traditional outdoor climbing, skiing, and traversing via ferratas that have become sports ...

and author

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

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

Morioka is the capital Cities of Japan, city of Iwate Prefecture located in the Tōhoku region of northern Japan. On 1 August 2023, the city had an estimated population of 283,981 in 132,719 households, and a population density of . The total area of t ...

. Much of the mountain is within the borders of the

Towada-Hachimantai National Park Towada-Hachimantai National Park is a national park comprising two separate areas of Aomori, Iwate, and Akita Prefectures, Japan. The Towada-Hakkōda area encompasses Lake Towada, Mount Hakkōda, and most of the chimantai area includes Mount ...

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

Mount Fuji is an active stratovolcano located on the Japanese island of Honshu, with a summit elevation of . It is the highest mountain in Japan, the second-highest volcano on any Asian island (after Mount Kerinci on the Indonesian island of Sumatra), a ...

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: ) 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 a tourist attraction for its deep blue color and water clarity. T ...

called Lake Onawashiro. Several somma 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 i ...

; however, the eruption of 1732 was much larger and resulted in a substantial

lava flow Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...

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 cultural feature of outstanding or unique value because of its inherent rarity, representative of aesthetic qualities, or cultural significance. They can be natural geological and geographical features such as w ...

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. Panoramic around the crater of Mount Iwate

Panoramic around the crater of Mount Iwate

References

External links

* - Japan Meteorological Agency
Iwate Volcano
- Geological Survey of Japan
Iwatesan
- Smithsonian Institution: Global Volcanism Program
Mt. Iwate
- Hiking in Japan
Iwate Prefectural 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