Template:Short description Template:Use dmy dates Template:Infobox mountain
Template:Nihongo is an active complex volcano in central Honshū, the main island of Japan. The volcano is the most active on Honshū.<ref name="Smithsonian" /> The Japan Meteorological Agency classifies Mount Asama as rank A.<ref name="qvoj-list"/> It stands Template:Convert above sea level on the border of Gunma and Nagano prefectures.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> It is included in 100 Famous Japanese Mountains.
GeologyEdit
Mount Asama sits at the conjunction of the Izu–Bonin–Mariana Arc and the Northeastern Japan Arc.<ref name="Smithsonian">Template:Cite gvp</ref> The mountain is built up from non-alkali mafic and pyroclastic volcanic rocks dating from the Late Pleistocene to the Holocene.<ref name="Semless">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The main rock types are andesite and dacite.<ref name="QVoJ"/>
Scientists from the University of Tokyo and Nagoya University completed their first successful imaging experiment of the interior of the volcano in April 2007. By detecting sub-atomic particles called muons as they passed through the volcano after arriving from space, the scientists were able gradually to build up a picture of the interior, creating images of cavities through which lava was passing deep inside the volcano.<ref>Template:Cite journal</ref>
A University of Tokyo volcano observatory is located on the mountain's east slope. Volcanic gas emissions from this volcano are measured by a Multi-Component Gas Analyzer System, which detects pre-eruptive degassing of rising magmas, improving prediction of volcanic activity.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
There is also another mountain called Asama (朝熊山, Asama-yama) of only 555 meters in Mie Prefecture.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Eruptive historyEdit
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The geologic features of this active volcano are closely monitored with seismographs and strategically positioned video cameras.<ref name="seach1">VolcanoLive.com: Asama</ref> Scientists have noted a range of textural variety in the ash which has been deposited in the region during the serial eruptions since the Tennin eruption of 1108.<ref>Yasui, Maya, Takahashi Masaki, and Sakagami Masakuki. "Textural Variety in the Eruptive Products of Vulcanian Eruptions between 1108 A.D. and 2004 A.D. on Asama-Maekake Volcano," Bulletin of the Volcanological Society of Japan (Kazan). Vol. 50, No. 6 (2005). pp. 501–517.</ref>
Tennin eruption (1108)Edit
The eruption of Mount Asama in 1108 (Tennin 1) has been the subject of studies by modern science.<ref>Centre national de la recherche scientifique (CNRS) Template:Webarchive, France: Yoshida, Minoru and Aoyagi, Ryugi. "Fluorine and chlorine contents in the products of the 1108 (Tennin) eruption of Asama volcano," Bulletin of the Volcanological Society of Japan (Kazan). Vol. 49, No. 4 (2004). pp. 189–199.</ref> Records suggest that the magnitude of this plinian eruption was twice as large as that of the Tenmei catastrophe in 1783.<ref>Hayakawa, Yukio and Hideko Nakajima. "Volcanic Eruptions and Hazards of Asama Written in Historical Records" (abstract), Bulletin of the Volcanological Society of Japan (Kazan). 19 July 2006.</ref>
A Swiss research team found Mount Asama's volcanic eruption could have contributed to extreme weather that caused severe famine, torrential rain and consecutive cold summers in Europe. They studied ice cores in Greenland which had increased sulfate deposition in 1108 CE. In the late Heian Period (794–1185) the diary of the court noble Fujiwara no Munetada reported that Mount Asama erupted on 29 August 1108. He wrote that a local report described rice paddies and fields could not be farmed due to being covered by a thick layer of ash.<ref name="Swiss-study">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Tenmei eruption (1783)Edit
Mount Asama erupted in 1783 (Tenmei 3), causing widespread damage.<ref>Titsingh, Isaac. (1834). Annales des empereurs du japon, p. 420.</ref> The three-month-long plinian eruption that began on 9 May 1783, produced andesitic pumice falls, pyroclastic flows, lava flows, and enlarged the cone. The climactic eruption began on 4 August and lasted for 15 hours,<ref name="Richards2003">Template:Cite book</ref> and contained pumice falls and pyroclastic flows.<ref name="seach1"/> The complex features of this eruption are explained by rapid deposits of coarse pyroclastic ash near the vent and the subsequent flows of lava; and these events which were accompanied by a high eruption plume which generated further injections of pumice into the air.<ref>Yasui, Maya and Takehiro Koyaguchi. "Sequence and eruptive style of the 1783 eruption of Asama Volcano, central Japan: a case study of an andesitic explosive eruption generating fountain-fed lava flow, pumice fall, scoria flow and forming a cone," Journal Bulletin of Volcanology (Kasan). Vol. 66, No. 3 (March 2004). pp. 243–262.</ref>
1982 eruptionEdit
Explosive eruptions occurred at the summit of Asama volcano on 26 April. Fine ash fell in Tokyo, Template:Convert to the SE, for the first time in 23 years.<ref name="seach1"/>
1983 eruptionsEdit
An explosive eruption occurred on 8 April. Incandescent tephra was ejected, and ash fell Template:Convert from the volcano.<ref name="seach1"/>
1995 earthquakesEdit
In April 1995, more than 1000 earthquakes were detected at the volcanic mountain.<ref name="seach1"/>
2004 eruptionEdit
A single vulcanian eruption occurred at Asama volcano at 11:02 UT on 1 September 2004. Incandescent blocks were ejected from the summit and caused many fires.<ref name="seach1"/> The eruption sent ash and rock as far away as Template:Convert.<ref name="BBC1" />
2008 eruptionsEdit
Three small ash eruptions occurred at Asama volcano in August 2008. This was the first activity at the volcano since 2004.<ref name="seach1"/>
2009 eruptionsEdit
Mount Asama erupted in early February 2009, sending ash to a height of Template:Convert,<ref name="BBC1">"Volcano erupts close to Tokyo," BBC. 2 February 2009.</ref> and throwing rocks up to Template:Cvt from the crater. Ash fall was reported in Tokyo, Template:Convert southeast of the volcano crater. On 16 February there were 13 recorded volcanic earthquakes and an eruption emitting smoke and ash in a cloud Template:Convert high.
Mount Asama continued to have small eruptions, tremors and earthquakes in February and remained on level-3 alert, with a danger zone within Template:Cvt of the crater.<ref name="Japanese Meteorological Agency">[1] Template:Webarchive 18 February 2009.</ref>
2019 eruptionEdit
A small eruption occurred on August 7th, 2019, with smoke reaching about 1,800 meters above the mountain.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Marking the span of Japan's historyEdit
The eruptions of Mount Asama mark the span of Japan's recorded history, including: 2019, 2009, 2008, 2004, 2003, 1995, 1990, 1983, 1982, 1973, 1965, 1961, 1958–59, 1953–55, 1952, 1952, 1950–51, 1949, 1947, 1946, 1944–45, 1938–42, 1935–37, 1934, 1934, 1933, 1931–32, 1930, 1929, 1929, 1927–28, 1924, 1922, 1920–21, 1919, 1918?, 1917, 1916, 1915, 1914, 1909–14, 1908, 1908, 1907, 1907, 1906, 1905?, 1904, 1903, 1902, 1902, 1900–01, 1899, 1899, 1894, 1889, 1879, 1878?, 1875, 1869, 1815, 1803, 1803, 1783, 1779?, 1777, 1776, 1769, 1762, 1755, 1754, 1733, 1732, 1731, 1729, 1729, 1728, 1723, 1723, 1722, 1721, 1720, 1719, 1718, 1717, 1711, 1710, 1708–09, 1706, 1704, 1703, 1669, 1661, 1661, 1660, 1659, 1658, 1657, 1656, 1655, 1653, 1652, 1651, 1650?, 1649, 1648, 1648, 1647, 1645, 1644, 1609, 1605, 1604, 1600, 1598, 1597, 1596, 1596, 1595?, 1591, 1590, 1532, 1528, 1527, 1518, 1427?, 1281, 1108, 887, 685.<ref name="seach1"/>
Note: The dates of eruptions featured in this article appear in bold italics.
OnioshidashiEdit
Template:Multiple image Onioshidashi (Template:Langx) "expelling demons" is the name of a lava flow on the northern slope of Mount Asama.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The lava flow that erupted in 1783 Tenmei eruption was solidified.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Now, it is known as a tourist destination.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Asama Volcano MuseumEdit
The Asama Volcano Museum (Template:Nihongo2), Template:Convert from the crater of the Mount Asama,<ref name="yomiuri">浅間火山博物館閉館へ, 『読売新聞』(Yomiuri Shimbun), 8 August 2020. Accessed 1 July 2021.</ref> open from 1993 to 2020, explained volcanoes.
The museum was in Naganohara-machi, Agatsuma-gun, Gunma Prefecture. As of early 2009, it was open from April until November.
Visitor numbers peaked at 265,000 in 1994; however, seismic activity at nearby Mount Asama was one reason for frequent closures. The closures were a factor in the drop in visitors:<ref name="jomo">浅間火山博物館を閉館 年度内に長野原町 新型コロナで休館中, 『上毛新聞』 (Jōmō Shinbun), 9 August 2020. Accessed 1 July 2021.</ref> this gradually fell to 23,000.<ref name="yomiuri" /> In the later years of the museum, most of the visitors were on school excursions.<ref name="jomo" /> The museum was running a deficit of about 17 million yen per year, paid for by the town of Naganohara. Additionally, the building was ageing, and maintenance threatened to cost hundreds of millions of yen.<ref name="yomiuri" /><ref name="jomo" />
A nearby building, Asama memorial hall (Template:Nihongo2) exhibited motorbikes; the plan in summer 2020 was to move these to a municipally owned tourist facility, Asama pasture (Template:Nihongo2), and to move some of the exhibits of the volcano museum to the memorial hall.<ref name="yomiuri" />
GalleryEdit
- Mt.Asama2 (From saku city).jpg
Viewed from the south
- 220929 Mt Asama Karuizawa Nagano pref Japan01s3.jpg
Viewed from the southeast
- Mt asama.jpg
Viewed from the SSE
- Mt.Asama (From onioshidashi).jpg
Viewed from the north
- Kisokaido03 Urawa.jpg
In popular cultureEdit
Mount Asama served as the backdrop to Japan's first colour film, Carmen Comes Home.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Several references are made to Mount Asama throughout the film, including a melody composed by a blind composer, Mr. Taguchi.
In the anime Neon Genesis Evangelion, the Eighth Angel, Sandalphon, was located inside Mount Asama.<ref name="FujieBooks2004">Template:Cite book</ref>
See alsoEdit
NotesEdit
ReferencesEdit
- Hall, John Whitney (1955). Tanuma Okitsugu, 1719–1788: Forerunner of Modern Japan, Cambridge: Harvard University Press.
- Hayakawa, Yukio and Hideko Nakajima. "Volcanic Eruptions and Hazards of Asama Written in Historical Records" (abstract), Bulletin of the Volcanological Society of Japan (Kazan). 19 July 2006.
- Screech, Timon (2006). Secret Memoirs of the Shoguns: Isaac Titsingh and Japan, 1779–1822. London: RoutledgeCurzon. Template:ISBN (cloth); Template:ISBN (electronic)
- Titsingh, Isaac (1834). [Siyun-sai Rin-siyo/Hayashi Gahō, 1652], Nipon o daï itsi ran; ou, Annales des empereurs du Japon. Paris: Oriental Translation Fund of Great Britain and Ireland.
External linksEdit
- Asamayama – Japan Meteorological Agency Template:In lang
- {{#invoke:citation/CS1|citation
|CitationClass=web }} – Japan Meteorological Agency
- Asama Volcano – Geological Survey of Japan
- Asamayama – Smithsonian Institution: Global Volcanism Program