Laacher See
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| Laacher See | |
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| Lake in summer; Maria Laach Abbey visible in the background | |
| Location | Rhineland-Palatinate |
| Coordinates | 50°25′N 7°16′E / 50.417°N 7.267°ECoordinates: 50°25′N 7°16′E / 50.417°N 7.267°E |
| Lake type | crater lake, caldera lake |
| Basin countries | Germany |
| Surface area | 3.3 km2 (1.3 sq mi) |
| Max. depth | 53 m (174 ft) |
| Surface elevation | 275 m (902 ft) |
Laacher See (German pronunciation: [ˈlaːxɐ ˈzeː]) or Laach Lake (in English) is a caldera lake and a potentially active volcano, in Rhineland-Palatinate, Germany, situated close to the cities of Koblenz (24 km), and Bonn (37 km), and closest to the towns Andernach (8 km), and Mayen (11 km). The caldera lake lies just 8 km from the river Rhine at Andernach. Just like the nearby 'Wehrer Kessel' volcano and Rieden volcano, the Laacher See volcano forms a volcanic caldera in the Eifel mountain range. It is part of the area called "East Eifel volcanic field".
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[edit] Description
The great Eifel lake takes its name from the Old High German word "lacha" which in turn is derived from Latin "lacus" as English "lake". Thus the name literally means "Lake of the Lake" similar to the "Loch Lochy" in the Scottish Highlands with the same meaning.
The lake lies 259 m above sea level, is 8 km in circumference, and surrounded by a ring of high hills. The water is blue, very cold and bitter to the taste. The lake has no natural outlet and so the water level changes considerably due to evaporation and rainfall conditions. On the western side lies the Benedictine monastery of Maria Laach Abbey (Abbatia Lacensis), founded in 1093 by Henry II of Laach of the House of Luxembourg, first count palatine of the Rhine who has had his castle opposite to the monastery above the eastern lakeside.
The caldera was formed after the colossal Laacher See eruption dated to 12,900 years ago.[1][2][3] The remaining crust collapsed into the empty magma chamber below, probably two or three days after the eruption.[4] An estimated 6 km³ of magma was erupted,[5] producing around 16 km³ of tephra.[6] This massive eruption thus had a Volcanic Explosivity Index (VEI) of 6, and was larger than the colossal 1991 eruption of Mount Pinatubo (Philippines) which also had a VEI of 6 (10 km³ of tephra erupted).
Tephra deposits from the eruption dammed the Rhine, creating a 140 km2 (50 sq mi) lake. When the dam broke, an outburst flood swept downstream, leaving deposits as far away as Bonn.[5]
The Laacher eruption coincides with the onset of the abrupt Younger Dryas re-glaciation, which brought renewed very cold conditions to the northern hemisphere from 12.9 to 11.6 ka. However, any relationship between this climate change and the eruption is speculative; eruptions of the size of the Laacher See eruption usually cause only short-term global cooling.
Remains of this eruption can be found all over Europe and the tephra is often used for dating of sediments.[7][8] A number of unique minerals can be found in the region,[9] and quarries mine the stone as a building material.
The Laacher See is a potentially active volcano, proven by seismic activities and heavy thermal anomalies under the lake. Carbon dioxide gas from magma still bubbles up at the southeastern shore [10].
[edit] See also
[edit] References
- ^ van den Bogaard, P (1995). 40Ar/(39Ar) ages of sanidine phenocrysts from Laacher See Tephra (12,900 yr BP): Chronostratigraphic and petrological significance
- ^ de Klerk et al. (2008). Environmental impact of the Laacher See eruption at a large distance from the volcano: Integrated palaeoecological studies from Vorpommern (NE Germany)
- ^ Baales, Michael; Jöris, Olaf; Street, Martin; Bittmann, Felix; Weninger, Bernhard; Wiethold, Julian (November 2002). "Impact of the Late Glacial Eruption of the Laacher See Volcano, Central Rhineland, Germany". Quaternary Research 58 (3): 273–288. doi:10.1006/qres.2002.2379.
- ^ Assembly area: Laacher lake (German)
- ^ a b Schmincke, Hans-Ulrich; Park, Cornelia; and Harms, Eduard (1999). "Evolution and environmental impacts of the eruption of Laacher See Volcano (Germany) 12,900 a BP". Quaternary International 61 (1): 61–72. doi:10.1016/S1040-6182(99)00017-8.
- ^ P.v.d. Bogaard, H.-U. Schmincke, A. Freundt and C. Park (1989). Evolution of Complex Plinian Eruptions: the Late Quarternary (sic) Laacher See Case History, "Thera and the Aegean World III", Volume Two: "Earth Sciences", Proceedings of the Third International Congress, Santorini, Greece, 3–9 September 1989. pp. 463–485.
- ^ Bogaard, P. v. d.; Schmincke, Hans-Ulrich (1985). "Laacher See Tephra: A widespread isochronous late Quaternary tephra layer in central and northern Europe". Geological Society of America Bulletin 96 (12): 1554–1571. doi:10.1130/0016-7606(1985)96<1554:LSTAWI>2.0.CO;2. ISSN 0016-7606.
- ^ Bogaard, Paul van den (1995). "40Ar/39Ar ages of sanidine phenocrysts from Laacher See Tephra (12,900 yr BP): Chronostratigraphic and petrological significance". Earth and Planetary Science Letters 133 (1–2): 163–174. Bibcode 1995E&PSL.133..163V. doi:10.1016/0012-821X(95)00066-L.
- ^ Ginibre, Catherine; Wörner, Gerhard; Kronz, Andreas (2004). "Structure and Dynamics of the Laacher See Magma Chamber (Eifel, Germany) from Major and Trace Element Zoning in Sanidine: a Cathodoluminescence and Electron Microprobe Study". Journal of Petrology 45 (11): 2197–2223. doi:10.1093/petrology/egh053.
- ^ National Geographic. 1986 #9
This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed (1911). Encyclopædia Britannica (11th ed.). Cambridge University Press.
[edit] Further reading
- Park, Cornelia; Schmincke, Hans-Ulrich (1997). "Lake Formation and Catastrophic Dam Burst during the Late Pleistocene Laacher See Eruption (Germany)". Naturwissenschaften 84 (12): 521–525. doi:10.1007/s001140050438.
- Riede, Felix (2008). "The Laacher See-eruption (12,920 BP) and material culture change at the end of the Allerød in Northern Europe". Journal of Archaeological Science 35 (3): 591–599. doi:10.1016/j.jas.2007.05.007.
[edit] External links
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Wikimedia Commons has media related to: Maria Laach |
- Nixdorf, B.; et al. (2004), "Laacher See" (in German), Dokumentation von Zustand und Entwicklung der wichtigsten Seen Deutschlands, Berlin: Umweltbundesamt, pp. 28, http://www-docs.tu-cottbus.de/gewaesserschutz/public/projekte/uba_2/09_nrw_rheinl_saar.pdf#page=28
- Apokalypse im Rheintal (Cornelia Park und Hans-Ulrich Schmincke)
