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| THE ASAHI SHIMBUN/GETTY IMAGES |
The above image shows a dirty thunderstorm within the plume on the southeast side of the volcano. Gas bubbles pop inside the volcano cause powerful explosions. Electrical charges are generated when rock fragments, ash, and ice particles in a volcanic plume collide and produce static charges, just as ice particles collide in regular thunderstorms. Volcanic eruptions also release large amounts of water, which may help fuel these thunderstorms.
Dirty thunderstorms typically are rare, but they’re common at Mount Sakurajima, Alaska's Mount Augustine, Iceland's Eyjafjallajökull volcano, Chaiten Volcano in Chile, and Mount Etna in Italy.
This article is about the volcano not the radish.
Sakurajima (Japanese: 桜島, lit. "Cherry Blossom Island") is an active composite volcano (stratovolcano) and a former island in Kagoshima Prefecture in Kyushu, Japan.[1] The lava flows of the 1914 eruption caused the former island to be connected with the Osumi Peninsula.[2]
The volcanic activity still continues, dropping large amounts of volcanic ash on the surroundings. Earlier eruptions built the white sands highlands in the region. As of September 2015, the volcano is under a Level 3 (orange) alert by the Japan Meteorological Agency, signifying the volcano is active and should not be approached.[3] The most recent eruption started on February 5, 2016.[4]
Sakurajima is a strato mountain. Its summit has three peaks, Kita-dake (northern peak), Naka-dake (central peak) and Minami-dake (southern peak) which is active now.
Kita-dake is Sakurajima's highest peak, rising to 1,117 m (3,665 ft) above sea level. The mountain is located in a part of Kagoshima Bay known as Kinkō-wan. The former island is part of the city of Kagoshima.[5] The surface of this volcanic peninsula is about 77 km2 (30 sq mi).
Sakurajima is located in the Aira caldera and formed in an enormous eruption 22,000 years ago.[6] Several hundred cubic kilometres of ash and pumice were ejected, causing the magma chamber underneath the erupting vents to collapse. The resulting caldera is over 20 km (12 mi) across. Tephra fell as far as 1,000 km (620 mi) from the volcano. Sakurajima is a modern active vent of the same Aira caldera volcano.
Sakurajima was formed by later activity within the caldera, beginning about 13,000 years ago.[7] It lies about 8 km (5 mi) south of the centre of the caldera. Its first eruption in recorded history occurred in 963 AD.[8] Most of its eruptions are strombolian,[8] affecting only the summit areas, but larger plinian eruptions have occurred in 1471–1476, 1779–1782 and 1914.[9]
Volcanic activity at Kita-dake ended around 4,900 years ago: subsequent eruptions have been centered on Minami-dake.[10] Since 2006 activity has centred on Showa crater, to the East of the summit of Minami-dake.[11]
Nussbaum, Louis-Frédéric. (2005). "Sakurajima" in Japan Encyclopedia, p. 814; see photo, caption -- Kagoshima after Sakurashima eruption, Illustrated London News. January 1914.
Jump up ^ Davison C (1916-09-21). "The Sakura-Jima Eruption of January, 1914". Nature 98: 57–58. Bibcode:1916Natur..98...57D. doi:10.1038/098057b0.
Jump up ^ Japan Meteorological Agency: Volcano Warnings
Jump up ^ "Mount Sakurajima erupts in fiery blast". The Japan Times. 5 February 2016. Retrieved 5 February 2016.
Jump up ^ Nussbaum, "Kagoshima prefecture" at p. 447.
^ Jump up to: a b c d e f g "The 1914 Sakurajima explosion at Volcanoworld". Retrieved 2007-08-03.
Jump up ^ "Sakurajima at Activolcan.info" (in French). Retrieved 2007-08-03.
^ Jump up to: a b c "Sakura-jima, Japan". VolcanoWorld. Oregon State University. Archived from the original on 2008-08-01. Retrieved 2008-10-12.
Jump up ^ "Sakurajima at the Earthquake Research Institute, University of Tokyo.". Retrieved 2007-08-03.
Jump up ^ "Sakura-jima". Global Volcanism Program. Smithsonian Institution. Retrieved 2007-08-04.
Jump up ^ Iguchi, Masato (20 July 2013). "Forecasting volcanic activity of Sakurajima" (PDF). Proceedings of IAVCEI 2013 Scientific Assembly. Retrieved 18 August 2013.
