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Volcanology 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 over a hot spot. Nearly thirty volcanoes are known to have erupted in the Holocene epoch; these include Eldgjá, source of the largest lava eruption in human history. 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). Two lateral volcanic zones play a minor role: Öræfi Volcanic Belt (ÖVB) and Snæfellsnes Volcanic Belt (SVB). Outside of the main island are the Reykjanes Ridge (RR), as part of the ... [...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 August 29, 2014 and ended on February 27, 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 2011 eruption of Grímsvötn, 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 Harmonic tremor, 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, comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Volcanic Zone
East or Orient is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth. Etymology As in other languages, the word is formed from the fact that east is the direction where the Sun rises: ''east'' comes from Middle English ''est'', from Old English ''ēast'', which itself comes from the Proto-Germanic *''aus-to-'' or *''austra-'' "east, toward the sunrise", from Proto-Indo-European *aus- "to shine," or "dawn", cognate with Old High German ''*ōstar'' "to the east", Latin ''aurora'' 'dawn', and Greek ''ēōs'' 'dawn, east'. Examples of the same formation in other languages include Latin oriens 'east, sunrise' from orior 'to rise, to originate', Greek ανατολή anatolé 'east' from ἀνατέλλω 'to rise' and Hebrew מִזְרָח mizraḥ 'east' from זָרַח zaraḥ 'to rise, to shine'. '' Ēostre'', a Germanic goddess of dawn, might have been a personification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grímsvötn
Grímsvötn (; ''vötn'' = "waters", singular: ) is a volcano with a (partially subglacial) fissure system located in Vatnajökull National Park, Iceland. The volcano itself is completely subglacial and located under the northwestern side of the Vatnajökull ice cap. The subglacial caldera is at , at an elevation of . Beneath the caldera is the magma chamber of the Grímsvötn volcano. Grímsvötn is a basaltic volcano which has the highest eruption frequency of all the volcanoes in Iceland and has a southwest-northeast-trending fissure system. The massive climate-impacting Laki fissure eruption of 1783–1784 was a part of the same fissure system. Grímsvötn was erupting at the same time as Laki during 1783, but continued to erupt until 1785. Because most of the volcanic system lies underneath Vatnajökull, most of its eruptions have been subglacial and the interaction of magma and meltwater from the ice causes phreatomagmatic explosive activity. Jökulhlaup Eruptions in the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Iceland
The recorded history of Iceland began with the settlement by Viking explorers and the people they enslaved from the east, particularly Norway and the British Isles, in the late ninth century. Iceland was still uninhabited long after the rest of Western Europe had been settled. Recorded settlement has conventionally been dated back to 874, although archaeological evidence indicates Gaelic monks from Ireland, known as papar according to sagas, had settled Iceland earlier. The land was settled quickly, mainly by Norwegians who may have been fleeing conflict or seeking new land to farm. By 930, the chieftains had established a form of governance, the ''Althing'', making it one of the world's oldest parliaments. Towards the end of the tenth century, Christianity came to Iceland through the influence of the Norwegian king Olaf Tryggvason. During this time, Iceland remained independent, a period known as the Old Commonwealth, and Icelandic historians began to document the nation's hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magma Chamber
A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces buoyant forces on the magma that tend to drive it upwards. If the magma finds a path to the surface, then the result will be a volcanic eruption; consequently, many volcanoes are situated over magma chambers. These chambers are hard to detect deep within the Earth, and therefore most of those known are close to the surface, commonly between 1 km and 10 km down. Dynamics of magma chambers Magma rises through cracks from beneath and across the crust because it is less dense than the surrounding rock. When the magma cannot find a path upwards it pools into a magma chamber. These chambers are commonly built up over time, by successive horizontal or vertical magma injections. Influx of new magma causes reaction of pre-existing crystals and the pressure in the chamber to increase. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shield Volcano
A shield volcano is a type of volcano named for its low profile, resembling a warrior's shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form. Shield volcanoes are found wherever fluid low-silica lava reaches the surface of a rocky planet. However, they are most characteristic of ocean island volcanism associated with hot spots or with continental rift volcanism. They include the largest volcanoes on earth, such as Tamu Massif and Mauna Loa. Giant shield volcanoes are found on other planets of the Solar System, including Olympus Mons on Mars and Sapas Mons on Venus. Etymology The term 'shield volcano' is taken from the German term ''Schildvulkan'', coined by the Austrian geologist Eduard Suess in 1888 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcano
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volcano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tjörnes Transform Zone
Tjörnes () is a peninsula situated at the northeast of Iceland, between the fjords of Öxarfjörður and Skjálfandi. Tjörnes is known for its particularly dense population of Rock Ptarmigan and the rich fossil record of Miocene - Pliocene age. The submarine volcano There is a submarine volcano north of Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ... named the ''Tjornes Fracture Zone''. It is a series of underwater fissure vents that last erupted in 1868. References Peninsulas of Iceland {{Iceland-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Iceland Seismic Zone
South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both east and west. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþaz'' ("south"), possibly related to the same Proto-Indo-European root that the word ''sun'' derived from. Some languages describe south in the same way, from the fact that it is the direction of the sun at noon (in the Northern Hemisphere), like Latin meridies 'noon, south' (from medius 'middle' + dies 'day', cf English meridional), while others describe south as the right-hand side of the rising sun, like Biblical Hebrew תֵּימָן teiman 'south' from יָמִין yamin 'right', Aramaic תַּימנַא taymna from יָמִין yamin 'right' and Syriac ܬܰܝܡܢܳܐ taymna from ܝܰܡܝܺܢܳܐ yamina (hence the name of Yemen, the land to the south/right of the Levant). Navigation By convention, the ''bottom or down-facing side'' of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kolbeinsey Ridge
The Kolbeinsey Ridge is a segment of the Mid-Atlantic Ridge located to the north of Iceland in the Arctic Ocean. It is bounded to the south by the Tjörnes Fracture Zone, which connects the submarine ridge to the on-shore Northern Volcanic Zone rifting center in eastern Iceland. The volcanic islands Kolbeinsey and Grímsey lie along the Kolbeinsey Ridge. In 1992, Robert Huber and Karl Stetter discovered a new species of thermophilic bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ... here and named it '' A. pyrophilus''. See also * Aegir Ridge References Mid-Atlantic Ridge Underwater ridges of the Atlantic Ocean {{Tectonics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reykjanes Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge (a divergent or constructive plate boundary) located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. In the North Atlantic, the ridge separates the North American from the Eurasian Plate and the African Plate, north and south of the Azores Triple Junction respectively. In the South Atlantic, it separates the African and 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 inferred by Matthew Fontaine Maury in 1853, based on soundings by the USS ''Dolphin''. The existence of the ridge and it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
%2C_13._September_2014.JPG "Click for more on -> 2014–2015 Eruption Of Bárðarbunga")
