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Volcanoes Of Iceland
:''The volcano system in Iceland that started activity on August 17, 2014, and ended on February 27, 2015, is Bárðarbunga.'' :''The volcano in Iceland that erupted in May 2011 is Grímsvötn.'' Iceland experiences frequent volcanic activity, due to its location both on the Mid-Atlantic Ridge, a divergent tectonic plate boundary, and being over a hotspot. Nearly thirty volcanoes are known to have erupted in the Holocene epoch; these include Eldgjá, source of the largest lava eruption in human history. Some of the various eruptions of lava, gas and ash have been both destructive of property and deadly to life over the years, as well as disruptive to local and European air travel. Volcanic systems and volcanic zones of Iceland Holocene volcanism in Iceland is mostly to be found in the ''Neovolcanic Zone'', comprising the Reykjanes volcanic belt (RVB), the West volcanic zone (WVZ), the Mid-Iceland belt (MIB), the East volcanic zone (EVZ) and the North volcanic zone (NVZ). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2014–2015 Eruption Of Bárðarbunga
The 2014–2015 eruption of Bárðarbunga was a Hawaiian eruption in the Bárðarbunga volcanic system in Iceland, that began on 29 August 2014, and ended on 27 February 2015. The eruption emitted large volumes of sulphur dioxide and impacted air quality in Iceland. There was no effect on flights outside of the immediate vicinity due to a lack of a significant emission of volcanic ash. The eruption took place in the lava field of Holuhraun northeast of the Bárðarbunga caldera proper. Overview Seismic activity surrounding the Bárðarbunga volcano gradually increased from 2007 to 2014, with a brief pause during the nearby eruption at Grímsvötn in 2011. By the summer of 2014 activity reached a level similar to that just before the Grímsvötn eruption. In May 2014 there was a small earthquake sequence of about 200 events. GPS data recorded a displacement of 14 cm in the region since the beginning of the phase of unrest, compared to a figure of 2 cm over the res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lakagigar
Laki () or Lakagígar (, ''Craters of Laki'') is a volcanic fissure in the western part of Vatnajökull National Park, Iceland, not far from the volcanic fissure of Eldgjá and the small village of Kirkjubæjarklaustur. The fissure is properly referred to as Lakagígar, while Laki is a mountain that the fissure bisects. Lakagígar is part of a volcanic system centered on the volcano Grímsvötn and including the volcano Þórðarhyrna. It lies between the glaciers of Mýrdalsjökull and Vatnajökull, in an area of fissures that run in a southwest to northeast direction. The system erupted violently over an eight-month period between June 1783 and February 1784 from the Laki fissure and the adjoining volcano Grímsvötn. It poured out an estimated 42 billion tonnes or of basalt lava as well as clouds of poisonous hydrofluoric acid and sulfur dioxide compounds that contaminated the soil, leading to the death of over 50% of Iceland's livestock population, and the destruction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge (a Divergent boundary, divergent or constructive Plate tectonics, plate boundary) located along the floor of the Atlantic Ocean, and part of the List of longest mountain chains on Earth, longest mountain range in the world. In the North Atlantic, the ridge separates the North American plate, North American from the Eurasian plate and the African plate, north and south of the Azores triple junction. In the South Atlantic, it separates the African plate, African and South American plate, South American plates. The ridge extends from a junction with the Gakkel Ridge (Mid-Arctic Ridge) northeast of Greenland southward to the Bouvet triple junction in the South Atlantic. Although the Mid-Atlantic Ridge is mostly an underwater feature, portions of it have enough elevation to extend above sea level, for example in Iceland. The ridge has an average spreading rate of about per year. Discovery A ridge under the northern Atlantic Ocean was first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and because most of Earth's plate boundaries are underwater, most volcanoes are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes resulting from divergent tectonic activity are usually non-explosive whereas those resulting from convergent tectonic activity cause violent eruptions."Mid-ocean ridge tectonics, volcanism and geomorphology." Geology 26, no. 455 (2001): 458. https://macdonald.faculty.geol.ucsb.edu/papers/Macdonald%20Mid-Ocean%20Ridge%20Tectonics.pdf Volcanoes can also form where there is str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceland
Iceland is a Nordic countries, Nordic island country between the Atlantic Ocean, North Atlantic and Arctic Oceans, on the Mid-Atlantic Ridge between North America and Europe. It is culturally and politically linked with Europe and is the region's westernmost and most list of countries and dependencies by population density, sparsely populated country. Its Capital city, capital and largest city is Reykjavík, which is home to about 36% of the country's roughly 380,000 residents (excluding nearby towns/suburbs, which are separate municipalities). The official language of the country is Icelandic language, Icelandic. Iceland is on a rift between Plate tectonics, tectonic plates, and its geologic activity includes geysers and frequent Types of volcanic eruptions, volcanic eruptions. The interior consists of a volcanic plateau with sand and lava fields, mountains and glaciers, and many Glacial stream, glacial rivers flow to the sea through the Upland and lowland, lowlands. Iceland i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Volcano
A central volcano is a type of volcano formed by basalts and silica-rich volcanic rocks. They contain very few or no volcanic rocks of intermediate composition, such that they are chemically bimodal volcanism, bimodal. Large silicic eruptions at central volcanoes often result in the formation of one or more calderas. Central volcanoes can be stratovolcanoes or shield volcanoes. Central volcanoes undergo periodic eruptions throughout their lifetime, which can span more than a million years. In Iceland, volcanic systems are normally named after an associated central volcano. The largest known glaciovolcanism, glaciovolcanic central volcano on Earth is Mount Haddington, a glacier-covered shield volcano on James Ross Island in Antarctica. Examples Antarctica *Mount Discovery *Mount Morning Canada *Armadillo Peak *Ice Peak *Ilgachuz Range *Itcha Range *Level Mountain *Mount Edziza *Rainbow Range (Chilcotin Plateau), Rainbow Range *Spectrum Range Iceland *Askja *Eyjafjallajökull *K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theistareykjarbunga
Theistareykjarbunga (Þeistareykjarbunga, ) is a shield volcano in north-eastern Iceland with two fissure vents called Þeistareykjahraun and Borgahraun , and two cones: the Stórahversmór and the , Stóravíti . They both are currently extinct, although there is evidence suggesting the potential for activity such as recent localised uplift and seismicity. The multiple vents make up the Theistareykir (Þeistareykir) volcanic system, with more recent evidence that the former classification as a shield volcano is better considered an embryonic central volcano with associated fissure swarm, as rhyolite has erupted in a limited area. The recent lava has picrite, olivine tholeiite basalt characteristics but before the ice age there were basaltic andesite and rhyolite eruptions. There is a central high temperature geothermal area with numerous steam vents and fumaroles. This has been utilised by a 90 MWe power station. Eruptions There have been three dated eruptions, all VEI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krafla
Krafla () is a volcanic caldera of about in diameter with a long fissure zone. It is located in the north of Iceland in the Mývatn region and is situated on the Iceland hotspot atop the Mid-Atlantic Ridge, which forms the divergent boundary between the North American Plate and the Eurasian Plate. Its highest peak reaches up to and it is in depth. There have been 29 reported eruptions in recorded history. Overview Iceland sits astride the Mid-Atlantic Ridge; the western part of the island nation is part of the roughly westward-moving North American plate, while the eastern part of the island is part of the roughly eastward-moving Eurasian Plate. The north–south axis of the Mid-Atlantic Ridge splits Iceland in two, roughly north to south. Along this ridge many of Iceland's most active volcanoes are located; Krafla is one of these. Krafla includes the crater Víti , which contains a green lake. South of the Krafla area is Námafjall , a mountain, at the foot of which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Askja
Askja () is an active volcano situated in a remote part of the central highlands of Iceland. The name Askja refers to a complex of nested calderas within the surrounding Dyngjufjöll mountains, which rise to , ''askja'' meaning ''box'' or ''caldera'' in Icelandic. Geography The Askja central volcano is in diameter and is associated with the Askja volcanic system which has a long fissure swarm that extends north from beneath the Vatnajökull glacier towards the north coast of Iceland. The Hrúthálsar area which is to the north-east is now usually regarded as part of the system. The outer caldera of Askja, representing a prehistoric eruption, is about in area, and there is evidence of other later caldera-forming events within it. These include the main summit caldera, that is about in diameter, to its north-east the diameter Kollur caldera, and the 1875 Öskjuvatn caldera with a diameter of about . The main crater floor lies at about . The central volcano region i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Langjökull
Langjökull (, Icelandic for "long glacier") is the second largest ice cap in Iceland (), after Vatnajökull. It is situated in the west of the Icelandic interior or Highlands of Iceland and can be seen clearly from Haukadalur. It covers the higher parts of the Langjökull volcanic system. Its volume is and the ice is up to thick. The highest point of the ice cap (at ''Baldjökull'' at the northern end of Langjökull) is about above sea level. In the past, the largest recorded surface area was in 1840. Situation and form The glacier is roughly parallel to the direction of the country's active volcanic zone: north-east to south-west. It is about long and wide, and has a slightly narrower point roughly between the lake Hvítárvatn on the Kjölur mountain road to the east and the Þrístapajökull glacier to the west, near another smaller glacier, Eiríksjökull, which is not quite connected to Langjökull. It is the nearest large glacier to Reykjavík. The area o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hofsjökull
__NOTOC__ Hofsjökull (Icelandic language, Icelandic: "temple glacier", ) is the third largest ice cap in Iceland after Vatnajökull and Langjökull and covers the largest active central volcano in the country, which has the same name. It is situated in the west of the Highlands of Iceland and north of the mountain range Kerlingarfjöll, between the two largest glaciers of Iceland. Glacier It covers an area of , with the icecap top being , and bottom being at about . There are other summits relating to the underlying volcano with two being at . Hofsjökull is the source of several rivers including the Þjórsá, Iceland's longest river. Changes While all ice caps in Iceland have been losing volume since 1995, due to high precipitation in 2015 and low ablation during the previous cool summer, the Hofsjökull ice cap increased in mass, the first time in 20 years this had happened. Between 1989 and 2015, even allowing for that last years increase, the icecap had lost about 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
