Tjörnes (peninsula)
| Tjörnes | ||
.jpg) Húsavík |
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| Geographical location | ||
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| Coordinates | 66 ° 8 ′ 21 ″ N , 17 ° 6 ′ 10 ″ W | |
| Waters 1 | Skjálfandi ( Arctic Ocean ) | |
| Waters 2 | Öxarfjörður | |
 Tjörnes vineyards |
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Tjörnes is a large peninsula in the north of Iceland .
Surname
The name is a compound from isl. tjörn (= German pond ) and nes (= headland ).
geography
The peninsula is located in the north of Iceland, bordering Skjálfandi Bay to the west, the Arctic Ocean to the north and Öxarfjörður to the east .
On it is the homonymous municipality Tjörnes . Parts of the peninsula also extend to the municipality of Norðurþing , which surrounds Tjörnes to the east, south and west. The largest town is Húsavík , the administrative seat of the municipality of Norðurþing, on the west side of the Skjálfandi .
geology
Tjörnes is located on the western wing of the Tjörnes transform zone named after the peninsula. This geologically connects the Northern Volcanic Zone of Iceland (NVZ) with the Kolbeinsey Ridge . Thus Tjörnes is part of the active rift and volcanic zone of the Mid-Atlantic Ridge .
This means that Tjörnes can be affected by both plate movements and volcanic eruptions.
The main actors in this regard are a large tectonic fissure, the so-called Húsavík-Flatey-Fault, also Húsavík-Transform-Fault and the volcanic system of kireistareykir .
The tectonic fissure cuts through the urban area of Húsavík , where it can also be clearly seen and forms a natural harbor, and then runs into the mountains to the east to end in the central volcano Þeistareykjabunga . In its submarine continuation, it forms a 5–10 km wide and 3–4 km deep valley towards Kolbeinsey . Within the last 9 million years there has been a total shift of 60 km.
This manifests itself in sometimes violent tremors. The last major earthquake in the area so far took place in 1976 as part of the volcanic-tectonic episode on the Krafla . The hypocenter was near the town of Kópasker and the tremors reached a magnitude of 6.2.
paleontology
On the Tjörnes peninsula about 1200 m thick layers of sediment were found, the origin of which dates back about 4 million years, which document the phases of the earth's history since then. On the basis of the fossilized traces of mussels and microorganisms found there, climate changes in the Arctic can be reconstructed.
The subsoil consists of basalt layers that are around 8 million years old . Three clearly distinguishable layers of sediment build up on them . These are shallow sea deposits that are rich in clay and sand, as well as fluvial sandstones that were partially formed in former river mouths.
The oldest group, the tapes layers, are 4–3.5 million years old. Since the fossilized mussels found there now live in the North Sea , this suggests a warmer climate at that time.
The next layer is the Mactra layer . Their age is 3.5-2.5 million years. The fossils of this rock layer show that the climate is still considerably warmer, as the mussel species found in them now live in the mid-Atlantic as far as the Canary Islands .
The upper layer of mollusc-containing sediments, called seripes , bears witness to another climate change: the climate here was a little warmer than today, but colder than in the previous phase. What is most astonishing, however, is that in this layer one finds mussels from the Pacific , which speak for the opening of the Bering Strait at that time .
Web links
- IMMunda: The Tjörnes Peninsula: A site of different vegetation patterns in the North of Iceland , Acta Botanica Islandica 14-1, 2004 (PDF, English)
Individual evidence
- ^ HU Schmid: Dictionary Icelandic - German. Buske, Hamburg, 2001, p. 259.
- ^ HU Schmid: Dictionary Icelandic - German. Buske, Hamburg, 2001, p. 167.
- ↑ cf. Ísland Vega Atlas. Ed. Ferðakort, Reykjavík 2006, 17
- ↑ see e.g. Riedel, C., u. a .: First results from the North Iceland Experiment (PDF), Marine Geophysical Research, 2006, p. 1; doi: 10.1007 / s11001-006-9007-0
- ^ A b Thor Thordarson, Armann Hoskuldsson: Iceland. Classic Geology in Europe 3. Terra, Harpenden, 2002, p. 144.
- ↑ L. Passarelli et al .: A probabilistic approach for the classification of earthquakes as 'triggered' or 'not triggered' , Journal of Seismology, 2012; doi: 10.1007 / s10950-012-9289-4 .
- ↑ a b c d e f Thor Thordarson, Armann Hoskuldsson: Iceland. Classic Geology in Europe 3. Terra, Harpenden, 2002, pp. 140ff.
- ↑ Ari Trausti Guðmundsson: Living Earth. Facets of the geology of Iceland. Reykjavík, Mál og Menning, 2004, p. 377.