Super volcano

This article deals with the geological phenomenon supervolcano, for the television film of the same name see supervolcano (film) .

Well-known super volcanoes: _ VEI 8 ,_ VEI 7

Super volcanoes are the largest known volcanoes , which in contrast to "normal" volcanoes, due to the size of their magma chamber, do not build up volcanic cones during eruptions, but leave huge calderas in the ground. Super-eruptions are eruptions with the volcanic explosion index value 8 (VEI-8), with VEI-7 eruptions occasionally also being included. However, there is no scientifically exact definition. The specialist literature only adopted the term super volcano from media reports shortly after the turn of the millennium.

The last super volcano eruption occurred in the area of Lake Taupo (New Zealand) about 26,500 years ago. The time between the complete filling of the magma chamber and the subsequent eruption of such a super volcano is estimated at a few hundred to a few thousand years.

definition

False color satellite image of Lake Toba , a 100 km long and 30 km wide caldera of a super volcano

Super volcanoes have a particularly large magma chamber under the volcanic area. When erupting, they typically emit an amount of ejecta (lava, pyroclastics, dust, etc.) of at least 1000 km³. Under the Yellowstone volcano there is a magma chamber with a volume of around 10,000 km³ above a magma reservoir estimated at 46,000 km³. While the partially molten magma is enriched with gas over thousands of years, the area rises above the magma chamber. If the magma becomes critical due to the gas enrichment, it breaks through the overburden in several widely distributed places. Typically, this occurs in a ring shape due to the cracks in the ground that arise when the area above the magma chamber is lifted. The rock cover formed in this way sinks into the emptying magma chamber and thus forms the characteristic caldera ( cauldron ). The force of such an eruption is described with the volcanic explosion index value 8 (VEI-8) and higher. Hundreds or thousands of cubic kilometers of lava are thrown out of the magma chamber at supersonic speed up to 50 km high into the stratosphere and "rain" down within a radius of several 100 km. Volcanic dust is carried around the globe.

effect

Cross-section through a super volcano ( Long Valley Caldera )

Extremely hot pyroclastic currents cover a large area around the eruption site, they can reach up to 200 km and form a layer up to 200 m thick. Tsunamis are possible in the event of an outbreak near the coast . Years after the eruption there is still a risk of mudslides ( lahar ), which may a. Block rivers and cause floods. An area the size of a continent can be covered with ash.

The number of victims depends on the location of the supervolcano. All life is destroyed by the outbreak within a radius of around 100 km. Within a radius of several hundred kilometers, the load of layers of ash, especially when moisture is added, can cause roofs to collapse. Water and sewage systems, air traffic and electricity supply would be at risk. Mortality is high even at greater distances. Very fine volcanic dust with a diameter of less than 4 µm can get into the lungs through inhalation and cause short-term asthma and bronchitis attacks, long-term silicosis , lung cancer and COPD . The ash layer hinders the photosynthesis of plants, it can - depending on the thickness and dwell time of the tephra layer - impair their growth, up to and including death. Trees and bushes in particular can break from the weight of the tephra. If a cement-like layer forms due to rain or dew, the residence time of the tephra is extended and the recolonization of the areas delayed.

In addition to the primary damage caused by a super volcanic explosion, there is also a global climate catastrophe , also known as volcanic winter , in which temperatures worldwide drop by several degrees. The massive death of plants and animals threatens years of food shortage.

It is believed that super volcanoes were responsible for the extinction of species in the known eruptions . According to the controversial Toba catastrophe theory , mankind was reduced to a few thousand people when the Toba volcano erupted in Sumatra ( Indonesia ) 75,000 years ago . Relic of the outbreak is selected from the Caldera formed Tobasee .

activities

Supervolcanoes are currently being scientifically recorded worldwide, but their total number has not yet been conclusively determined. The best-known representative of this type is the Yellowstone in Yellowstone National Park . Other examples are the Phlegraean Fields in Italy, the Taupo in New Zealand and the La Garita Caldera in southwestern Colorado , USA .

The so far strongest volcanic eruption in the Quaternary is considered to be that of Toba on the Indonesian island of Sumatra around 74,000 years ago, for which a magnitude of 8.8 was calculated and which subsequently caused massive global temperature drops over a period of around ten years. According to the controversial Toba catastrophe theory of the anthropologist Stanley Ambrose , the consequences of this outbreak are said to have resulted in a “ genetic bottleneck ” among the hominids living at the time , which could explain the low genetic diversity of people living today.

Devastating volcanic systems are also the Trapps (from Scandinavian for "stairs"), which were active for a long time and thereby formed geological plateaus that clearly stand out from one another in the form of steps. The best known is the " Dekkan Trapp ", which is also associated with the extinction of the dinosaurs . The " Siberian Trapp " is considered to be the largest of its kind. It is associated with the mass extinction in the Permian and was active for around a million years. The "Etendeka Trapp" once stretched across the continents of West Africa and South America, which were then connected .

The Altiplano - Puna volcano complex in the triangle between Chile , Bolivia and Argentina with the active Uturuncu is also very active , with four other calderas (e.g. Vilama caldera ) being occupied.

The Lazufre volcanic field ( Ojos del Salado , Cerro de Azufre Lastarria and San Román ), which is named after the region between Lastarria and Cordón del Azufre on the border between Chile and Argentina, has hardly been explored . The Lazufre region stands out over an area of ​​1,750 km², in the center by 3 centimeters per year. The region is seismically much more active than, for example, the Yellowstone region. However, the Lazufre region has not been adequately researched scientifically and, due to its altitude, is only accessible to mountaineers.

frequency

According to a study published by researchers at the University of Bristol in the Earth and Planetary Science Letters at the beginning of November 2017 , supervolcanoes erupt with an explosion or eruption of at least Mag 8 every 5,200 to 48,000 years, around 10 times more often than in the previously assumed range of 45,000 to 714,000 years. The basis is a geological database covering the past 100,000 years; a last such eruption was therefore about 20,000 years ago.

Selection of supermassive explosive bursts

The data come from Partly from the database of the Volcano Global Risk Identification & Analysis Project (VOGRIPA), specifying the sources, although the scientists often have different opinions.

volcano	place	Country	Time of outbreak	Tephra deposit	Like	swell
Volcanic Explosivity Index 8
San Juan volcanic field ( La Garita Caldera )	Colorado	United States	about 27.8 million years ago	5,000 km³	9.2	lemma
Toba ( Tobasee ) (Young Toba Tuff)	Sumatra	Indonesia	about 74,000 years ago	2,800 km³	8.8
Toba ( Tobasee ) (Old Toba Tuff)	Sumatra	Indonesia	about 788,000 years ago	820 km³	8.4
Yellowstone Caldera (Lava Creek Eruption)	Wyoming	United States	about 640,000 years ago	1,000 km³	8.4
Yellowstone Caldera (Huckleberry Ridge eruption)	Wyoming	United States	about 2.1 million years ago, series of several eruptions with 1340 km³, 820 km³ and 290 km³	2,500 km³	8.8
Altiplano – Puna Volcano Complex (APVC) ( Vilama -Caldera)	El Tatio, Puna Region, Andes	Chile	about 8.4 million years ago	2,000 km³		lemma
Altiplano – Puna Volcano Complex (APVC) ( Guacha caldera)	Sol de Mañana , Puna region, Andes	Bolivia	about 5.6–5.8 million years ago	1,300 km³		?
Altiplano – Puna Volcano Complex (APVC) ( La Pacana Caldera)	Región de Antofagasta , Santa Cruz Region, Andes	Chile	about 3.5-3.6 million years ago	2,500 km³		?
Long Valley Caldera (Bishop Tuff)	California	United States	about 760,000 years ago	1,380 km³	8.3
Taupo ( Oruanui outbreak )	North island	New Zealand	about 26,500 years ago	1,170 km³	8.1
Taupo (Whakamaru eruption)	North island	New Zealand	about 254,000 years ago	1,170–2,000 km³		?
Corbetti (Awasa Caldera)	Awasa lake	Ethiopia	about 1 million years ago	1,000 km³	8.0
Volcanic Explosivity Index 7
Altiplano – Puna Volcano Complex (APVC) ( Pastos Grandes Caldera)	Potosí Department , Andes	Bolivia	about 2.89 million years ago	820 km³		?
Yellowstone Caldera (Mesa Fall Eruption)	Wyoming	United States	about 1.2 million or 1.6 million years ago	280-300 km³	7.8
Valles Caldera (Lower Bandelier)	New Mexico	United States	about 1.6 million years ago	690 km³	7.8
Aso (Jigoku eruption)	Kyushu	Japan	87,000 ± 9,000 BP , strongest eruption	600 km³	7.7
Aso	Kyushu	Japan	115,000 BP	150 km³	7.2
Aso	Kyushu	Japan	263,000 BP	100 km³	7.0
Aso (Hirose-3 eruption)	Kyushu	Japan	273,400 BP	100 km³	7.0
Atitlan (Los Chocoyos Ashes)	Central America	Guatemala	84,000 BP	420 km³	7.8
Kapenga (Waiotapu)	Fiji island	Fiji	710,000 BP	460 km³	7.7
Taupo (Reporoa eruption)	North island	New Zealand	about 230,000 years ago	340 km³		?
Taupo (Maroa eruption)	North island	New Zealand	about 230,000 years ago	140 km³		?
Taupo (Rotorua eruption)	North island	New Zealand	about 220,000 years ago	100 km³		?
Kos - Nisyros (Kos-Nisyros eruption)	Kos and Nisyros	Greece	about 161,000 years ago Separated Kos and Nisyros, Kos plateau tuff	110 km³	7.1
Changbaishan (Tianchi eruption)	Changbai Mountains	China	969 ± 30 AD	76-116 km³	7.4	lemma
Changbaishan (Oga eruption)	Changbai Mountains	China	about 448,000 years ago	70-100 km³	7.0
Maipo (Diamante Eruption)	San Carlos (Mendoza)	Chile / Argentina	about 450,000 years ago	450 km³	7.7
Bruneau-Jarbidge	Idaho	United States	about 10-12 million years ago	250 km³		?
Sabatini volcanic complex	Lazio	Italy	about 374,000 years ago	200 km³	7.3
Tambora	Sumbawa	Indonesia	1815 , " year without a summer "	110-160 km³	7.0	lemma
Samalas ( Eruption of Samala 1257 )	Lombok	Indonesia	1257 , "year without summer"	100 km³		lemma
Kikai (Akahoya eruption)	Ōsumi Islands	Japan	around 4350 BC Chr.	200 km³	7.2
Corbetti (Corbetti Caldera)	Awasa lake	Ethiopia	500,000 ± 60,000 years ago	103 km³
Mount Mazama	Crater Lake , Oregon	United States	around 5677 ± 150 BC BC (or 5724 ± 20 BC)	150 km³		lemma
Kuril lake (Ilinsky eruption)	Kamchatka	Russia	around 6440 ± 25 BC Chr.	155 km³	7.2
Aira	Kyushu	Japan	about 28,000 years ago	456 km³	7.7
Aira	Kyushu	Japan	about 456,000 years ago	100 km³	7.0
Santorini ( Minoan eruption )	Cyclades	Greece	1613 ± 13 BC Chr.	100 km³		lemma
Taupo (Hatepe eruption)	North island	New Zealand	181 . AD.	85-100 km³		lemma
Phlegraean Fields	Campania	Italy	about 39,000 years ago	320 km³	7.1
Phlegraean Fields	Campania	Italy	about 50,000 years ago	100 km³	7.0

Selection of supermassive effusive events

event	place	Country	Age (million years)	Covered area (million km²)	Lava volume (million km³)
Siberia Trapp	Putorana Mountains near Norilsk , Siberia	Russia	251-250	1.5-3.9	0.9-2.0
Dekkan Trapp (Mahabaleshwar – Rajahmundry Trapp)	Dekkan Plateau	India	066	0.5-0.8	0.5-1.0
Etendeka Trapp (Serra-Geral formation)	Paraná Basin and Etendeka Plateau	Brazil and Namibia / Angola	134-128	1.5	1
Emeishan Trapp	Emei Shan , Sichuan	China	263-259	0.25	0.3

reception

literature

• Ilya N. Bindemann: The elemental force of the super volcanoes . Spectrum of Science , pp. 38-45, August 2006, ISSN  0170-2971
• Clive Oppenheimer: Eruptions that Shook the World . (“Eruptions That Shook the World”), Cambridge University Press, 2011, ISBN 978-0-521-64112-8

Movie

• Supervolcano , USA 2005

Web links

Wiktionary: Supervulkan  - explanations of meanings, word origins, synonyms, translations

• Super volcanoes . Städtisches Theodolinden-Gymnasium, May 4, 2014,accessed on September 8, 2014(English). 
• scinexx.de: Supervolcanoes November 21, 2014
• Calvin F. Miller and David A. Wark: SUPERVOLCANOES AND THEIR EXPLOSIVE SUPERERUPTIONS (PDF, English; 992 kB)
• Peter L. Ward: Sulfur dioxide initiates global climate change in four ways. In: Thin Solid Films. 517, 2009, p. 3188, doi: 10.1016 / j.tsf.2009.01.005 . (List of volcanic eruptions with an impact on the world climate)
• Ben G. Maso, David M. Pyle, and Clive Oppenheimer: The size and frequency of the largest explosive eruptions on Earth . In: Bulletin of Volcanology . 66, No. 8, 2004, pp. 735-748. doi : 10.1007 / s00445-004-0355-9 .

Individual evidence

1. ↑ Vanderbilt University Press Release 2012: Super-eruptions may have surprisingly short fuses
2. ↑ Gualda, Pamukcu, Ghiorso, Anderson Jr, Sutton, et al .: Timescales of Quartz Crystallization and the Longevity of the Bishop Giant Magma Body . In: PLoS ONE . tape 7 , no. 5 , 2012, doi : 10.1371 / journal.pone.0037492 .
3. ↑ Definition of supervolcanoes from Yellowstone Volcano Observatory
4. ↑ Stephen Self: The effects and consequences of very large explosive volcanic eruptions . In: Philosophical Transactions of the Royal Society A . August 15, 2006, doi : 10.1098 / rsta.2006.1814 .
5. ↑ ^{a b c} Stephen Self: Explosive Super-Eruptions and Potential Global Impacts . In: Paolo Papale and John F. Shroder (Eds.): Volcanic Hazards, Risks and Disasters . 2015, ISBN 978-0-12-396453-3 , doi : 10.1016 / B978-0-12-396453-3.00016-2 .
6. ↑ CJ Horwell and PJ Baxter: The respiratory health hazards of volcanic ash: A review for volcanic risk mitigation . In: Bulletin of Volcanology . tape 69 , no. 1 , 2006, p. 1-24 , doi : 10.1007 / s00445-006-0052-y .
7. ↑ Paul Martin Ayris and Pierre Delmelle: The immediate environmental effects of tephra emission . In: Bulletin of Volcanology . 2012, p. 1914-1916 , 1926 , doi : 10.1007 / s00445-012-0654-5 .
8. ↑ Martin Williams: The ~ 73 ka Toba super-eruption and its impact: History of a debate . In: Quaternary International . 2012, doi : 10.1016 / j.quaint.2011.08.025 .
9. ↑ spiegel.de , March 26, 2012: Researchers discover the new super volcano Uturuncu in the Andes
10. ↑ ^{a b} German Research Center for Geosciences (GFZ) Potsdam, Thomas R. Walter, Joel Ruch, Andrea Manconi, Manoochehr Shirzaei, Mahdi Motagh, Jan Anderssohn, ebooks.gfz-potsdam.de: The "bump" of Lazufre
11. ↑ Jonathan Rougier, Stephen Sparks, Katharine Cashman, Sarah Brown: The global magnitude-frequency relationship for large explosive volcanic eruptions . In: Earth and Planetary Science Letters . November 8, 2017, ISSN  0012-821X ( bristol.ac.uk [accessed November 30, 2017]).
12. ↑ Geology - supervolcano eruptions more often than expected . In: Deutschlandfunk . ( deutschlandfunk.de [accessed November 30, 2017]).
13. ↑ ^{a b c d e f g h i j k l m n o p q r s t u v w x y z aa} VOGRIPA Database

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