Skaftá
| Skaftá | ||
 The mouth of Skaftá in the Atlantic Ocean, with the flat estuary Landbrot (left, front) and Eldhraun (right, back) |
||
| Data | ||
| location | Iceland | |
| source | Skaftárjökull, a valley glacier of Vatnajökull | |
| muzzle |
Atlantic Ocean , south coast of Iceland Coordinates: 63 ° 39 ′ 50 ″ N , 17 ° 48 ′ 0 ″ W 63 ° 39 ′ 50 ″ N , 17 ° 48 ′ 0 ″ W |
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| Mouth height |
0 m
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| length | 115 km | |
| Catchment area | 1400 km² | |
| Drain |
MQ HHQ |
100 m³ / s 1500 m³ / s |
| Left tributaries | Grjótá , Hellisá , Fjaðrá | |
| Right tributaries | Útfall , Nyðri-Ófærá , Syðri-Ófærá | |
| Small towns | Kirkjubæjarklaustur | |
The Skaftá River is a glacial river in the south of Iceland .
Most important dates
The catchment area of the river covers 1400 km², its average water volume 100 m³ / s, its length 115 km.
Numerous smaller rivers flow into the Skaftá, including source rivers and the Útfall , a river from Lake Langisjór . It rises in the northwest of Vatnajökull and flows in a large curve to the south, where it flows into the North Atlantic not far from Kirkjubæjarklaustur .
The northernmost farm on the river is called Skaftárdalur , where there was a ferry for travelers before the ring road was expanded.
course
Upper course of the Skaftá
On the upper reaches, the Skaftá flows from the highlands, between Skaftártunga and Síða and past several farms, the land of which is regularly inundated in smaller and larger parts during the glacier runs.
Above the Skaftádalur farm, the river forms a 9 m high waterfall, the Hundafoss .
Lower Skaftá
The river branches in its lower course on the Mýrdalssandur , so that the traveler on the ring road to the east crosses it three times between the village and the nearest place in the west, Vík í Mýrdal .
The westernmost branch flows partly underground into the Eldvatn , which in turn flows into the Kúðafljót . This has its origin in the Eldgjá and numerous tributaries from the Mýrdalsjökull . In the middle of the Mýrdalssandur are the so-called Árkvíslar , rivers and brooks, some of which seep under the lava cover and flow to the sea below. The easternmost branch is called Skaftá, flows as such through Kirkjubæjarklaustur and flows into the sea ten kilometers southeast of it as Breiðbalakvísl .
The influence of volcanism: Gjálp, Skaftárkatlar and Laki glacier volcanoes
Subglacial volcanoes: Grímsvötn, Gjálp
The origin of the Skaftá lies in the area of a volcano, which lies under the large glacier shield Vatnajökull, a little northwest of the central volcano Grímsvötn and is called Gjálp . Gjálp made a name for itself especially in 1996 with a volcanic eruption and subsequent large glacier run over the Skeiðarársandur .
Skaftárkatlar: Regular glacier runs
About 10 km northwest of the Grímsvötn you can see three burglary kettles in the ice field, the so-called Skaftárkatlar . The diameter of the largest is about 2.5–3 km and it is 100–150 m deep. Below that lies a fairly large high temperature area with an estimated capacity of 800 MW.
Similar to the Grímsvötn, a lake forms under a glacier cover once a year, only more regularly. This normally arises from the slow but steady thawing of the glacier ice by an underlying high temperature area . When the lake has reached a certain height, the glacier ice floats on it and a glacier flow flows out from under the Skaftárjökull glacier , which in the last few years and centuries has never reached catastrophic proportions in the Skaftá river and usually between 500 and 1500 m³ / s includes. Until 1954 there were repeatedly smaller glacier runs, often associated with volcanic activity under the glacier. After 1954 this seems to have increased. In 2010 there were two glacier runs from the Skaftárkatlar with a maximum amount of approx. 1,400 m³ / s on June 28, 2010, at the end of July 2011 a smaller glacier run began, probably from the western, smaller basin
The gases that these glacier runs of the Skaftá bring with them are dangerous and that in the vicinity of the glacier often exceed harmful limits in terms of sulfur dioxide content .
Volcanic eruptions near Laki in the 18th century and their influence on the Skaftá
Volcanic eruptions have also influenced the course of the river.
The splitting of the river dates from one of the most catastrophic events in Icelandic history, the volcanic eruptions of the Lakikrater in 1783. Large amounts of lava flowed down the river valley, and the river almost evaporated, as eyewitnesses report (the fire preacher and pastor Jón Steingrímsson from Kirkjubjarklaustur).
Other lava flows have also caused the river to deviate course, such as B. the one in the Eldgjá around 930 AD as well as several volcanic eruptions from prehistoric times, in Iceland this means: more than 1100 years ago. Because in the highlands, not far from Laki and the Eldgjá, there are also other volcanic fissure systems such as the Kambagígar , the Lambavatnsgígar and the Lyngfellsgígar . There are many other layers beneath the huge 1783 lava fields and most of the lava apparently flowed down this river bed.
See also
Web links
- Skaftá at Nat.is (English)
Individual evidence
- ↑ a b c d Íslandshandbókin. Náttúra, saga og sérkenni. 2. bindi. Edited by T. Einarsson, H. Magnússon. Örn og Örlygur, Reykjavík 1989, 718
- ↑ Vegahandbókin. Ed. Landmælingar Íslands. 2006, p. 127
- ↑ Skaftárhlaup í júní 2010 , Fréttir, Veðurstofa Íslands, June 28, 2010 (Icelandic); Accessed September 8, 2011
- ↑ Afleiðingar Skaftárhlaups , Fréttir, RÚV, July 13, 2010 (Icelandic); Accessed July 30, 2011
- ↑ Hlaupið í Skaftá, Fréttir, Veðurstofa Íslands, July 29, 2011 (Icelandic); Accessed September 8, 2011
- ↑ cf. also Aukið vatnsmagn í Skaftá , Vísir, July 30, 2011 (Icelandic); Accessed September 8, 2011
- ↑ Skaftárhlaup: Varað við Brennisteinsmengun , Vísir , June 20, 2010 (Icelandic); Accessed September 8, 2011
- ↑ cf. Web links, nat.is
- ↑ Íslandshandbókin, ibid.
- ↑ cf. Jon Steingrimsson (Author), Keneva Kunz (Translator): Fires of the Earth - The Laki Eruption 1783–1784. Nordic Volcanological Institute and the University of Iceland Press, Reykjavík 1998. ISBN 9979-54-244-6 (English translation of Jón Steingrimsson's notes)