Rauðhólar (Reykjavíkurborg)
Coordinates: 64 ° 5 ′ 43 " N , 21 ° 45 ′ 19" W.
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The Rauðhólar (Eng. "Red Hills") are a group of pseudocraters in the Icelandic capital city of Reykjavíkurborg .
geography
The hills are located in the Heiðmörk recreation area just west of the Hringvegur just outside the urban area of Reykjavík .
Volcanism
The craters were formed during volcanic eruptions in the Brennisteinsfjöll volcanic system around 4,700 years ago.
The lavas streamed down from the Bláfjöll mountain range into the plain, formed the Leitahraun lava field and covered a wetland in the process. Various lava caves, such as the Búri (cave), are located here.
The collision of hot lava with the water triggered phreatomagmatic explosions , in which the pseudocraters formed. They are a group of slag and weld slag cones that cover an area of approximately 1.2 km 2 . A map from 1912 shows the original extent of the field and the shape of the crater, the largest of which was 212 m in diameter. It rose 22 m above the plateau consisting of slag about 5 m thick and a 7 m thick layer of lava.
The damage to the craters brought their interior to light. You can see that the individual craters built up in a series of explosions over a long period of time.
The red color of the craters is explained by a high iron content .
Developments in the area
The group originally consisted of 150 pseudocraters. However, only a few of these still exist and numerous craters have also been severely damaged. This can be explained by years of material extraction, especially for road construction and the construction of Reykjavík airport by the Allies during the Second World War . The craters have been under nature protection since 1962. The area belongs to the Heiðmörk .
See also
Web links
Individual evidence
- ↑ T. Einarsson, H. Magnússon (eds.): Íslandshandbókin , 2. bindi, Reykjavík, Örn & Örlygur, 1989, p. 813
- ↑ cf. Thor Thordarsson, Armann Hoskuldsson: Iceland. Classic Geology in Europe , 3. Harpenden 2002, p. 55 ff.
- ↑ Thor Thordarsson, ibid., P. 56
- ↑ T. Einarsson, H. Magnússon (eds.): Íslandshandbókin , 1. bindi, Reykjavík, Örn & Örlygur, 1989, p. 34