Alnön
![]() False colorsatellite image of Alnö outside Sundsvall in the Gulf of Bothnia. | |
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Geography | |
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Location | Gulf of Bothnia |
Coordinates | 62°24′N17°28′E/ 62.400°N 17.467°E |
Area | 67.79 km2(26.17 sq mi)[1] |
Administration | |
County | Västernorrland |
Alnönis an island in theGulf of Bothniajust outsideSundsvallinMedelpad,Sweden. It has an area of 67.79 km2and a permanent population of 8,417 (as of 31 December 2010), although its summertime inhabitants are about twice that number. Most of the island's inhabitants work in Sundsvall and other towns on the mainland.
The island is 15 km long and 6 km wide on the widest spot. It is connected to the mainland by a 1,042-meter-long (3,419 ft) bridge, which was the longest bridge in Sweden when it was opened in 1964.
Evidences of habitation on the island predate theViking Age,and there are severaltumulion the island from that period. Theold stone churchnear the modern bridge was built in the 12th century. The island saw a population boom in the second half of the 19th century, due to the development of steam-drivensawmills.In 1850 the island had 950 inhabitants, mainly farmers and fishermen, but by 1900 the population had grown to almost 7,000, following the establishment of 18 sawmills between 1860 and 1897.
As result of decreased foreign trade duringWorld War IIapatitewas mined in Alnön from 1943 to 1945.[2]Apatite was separated byflotationbut results were meager.[2]While the separation process had improved in 1945 the end of the war the same year meant also apatite mining became unprofitable.[2]
Geology
[edit]Alnö was affected some 570 million years ago by a massivevolcanic eruption.The northeastern part of the island is rich incarbonateminerals, and it is one of few areas in the world with acarbonatitevolcanic complex.[3]Its chemistry is very different from the ordinary granitic rock that form the rest of the island, resulting in a number of unusual minerals, such asbaryteandaegirine.[4]
The most famous of therocksof Alnön is thealnoite,named from the Island, which is alamprophyrechiefly composed ofbiotiteorphlogopiteandmeliliteas essential minerals, commonly witholivine,calciteandclinopyroxene.Perovskite,apatite,nephelineandgarnetmay also be present.Diamondshave also been found on Alnön, but only in very small amounts.[5]
![](https://upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Aln%C3%B6bron.jpg/600px-Aln%C3%B6bron.jpg)
Sport
[edit]Notable citizens
[edit]- Vilma Abrahamsson, Football player
- Gunnar Hellström,Director
- Tina Nordlund,Football player
- Hjördis Schymberg,Opera singer
- Andreas Yngvesson,Football player
- Helen Sjöholm,Singer and actress
References
[edit]- ^"Statistisk årsbok 2011"(PDF)(in Swedish).Statistics Sweden.p. 12. Archived fromthe original(PDF)on 13 January 2012.Retrieved5 July2011.
- ^abcLundegårdh, Per H. (1971). "Apatit".Nyttosten i Sverige(in Swedish). Stockholm:Almqvist & Wiksell.p. 70.
- ^Andersson, Magnus; Malehmir, Alireza; Troll, Valentin R.; Dehghannejad, Mahdieh; Juhlin, Christopher; Ask, Maria (2013-04-17)."Carbonatite ring-complexes explained by caldera-style volcanism".Scientific Reports.3(1): 1677.doi:10.1038/srep01677.ISSN2045-2322.PMC3628075.PMID23591904.
- ^von Eckermann, Harry (1948).The Alkaline District of Alnö Island.Ca, Avhandlingar och uppsatser. Vol. 36. Stockholm: Sveriges geologiska undersökning. pp. 3–176.
- ^Kresten, Peter; Troll, Valentin R. (2018)."The Alnö Carbonatite Complex, Central Sweden".GeoGuide.doi:10.1007/978-3-319-90224-1.ISBN978-3-319-90223-4.ISSN2364-6497.S2CID135266142.