|
Múlakvísl
The Múlakvísl () is a river in the south of Iceland on the western side of Mýrdalssandur. Glacier flow The river has a glacier flow which draws its water from the Mýrdalsjökull, mainly through the glacier tongue Kötlujökull. The river's floods are usually of gray-brown color, since it carries much sediment with it. At Selfjall, about east of the village Vík í Mýrdal, the Ring Road goes across a bridge over the Múlakvísl. Jökulhlaups As increasing water levels of this river are an important indicator of Katla's upcoming volcanic eruptions, it is closely monitored. 1955 A predecessor of the present bridge was demolished in 1955, during a jökulhlaup with 2,500 m3/s of water. A fissure formed on Katla in 1918 in the caldera of the volcano, and a kettle had formed upon the glacier. This showed volcanic activities under the glacier, which in turn initiated the jökulhlaup. However, there was no real outbreak in 1955. July 2011 On 9 July 2011, another jökulhlaup o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mýrdalsjökull
Mýrdalsjökull (pronounced , Icelandic for "(the) mire dale glacier" or "(the) mire valley glacier") is an ice cap on the top of the Katla volcano in the south of Iceland. It is to the north of the town of Vík í Mýrdal and to the east of the smaller ice cap Eyjafjallajökull. Between these two glaciers is the Fimmvörðuháls pass. The glacier contributes to the most serious natural hazard area of Iceland. Setting The icecap of the glacier covers an active volcano. The caldera of Katla has a diameter of and the volcano erupts usually every 40–80 years. The last eruption took place in 1918. Scientists are actively monitoring the volcano, particularly after the eruption of nearby Eyjafjallajökull began in April 2010. There is a further historic relationship with Eyjafjallajökull as the two glaciers were continuous as a single ice cap at the end of the 19th century and only separated into the larger Mýrdalsjökull and smaller Eyjafjallajökull in the middle of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Katla (volcano)
Katla () is an active subglacial volcano in Farthings of Iceland, southern Iceland. This volcano has been very active historically with at least twenty documented major eruptions since 2920 BC. In its recent history though, Katla has been less active as the last major eruption occurred in 1918. These eruptions have had a Volcanic Explosivity Index (VEI) of between 4 and 5 on a scale of 0 to 8. In comparison, the Eyjafjallajökull 2010 eruption had a VEI of 4. Larger VEI-5 eruptions are comparable to Mount St. Helens 1980 eruption of Mount St. Helens, 1980 eruption. These eruptions have produced very large glacial outburst floods. Several smaller (minor) events measuring Volcanic explosivity index, VEI-1 and below have occurred since. Katla is one of the largest volcanic sources of Carbon dioxide, carbon dioxide (CO2) on Earth, accounting for up to 4% of total global volcanic carbon dioxide emissions. Geography and physical appearances Katla is one of the largest volcanoes in I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mýrdalssandur
Mýrdalssandur () is an outwash plain on the south coast of Iceland. Location and description The outwash plain is located between the rivers of Kúðafljót in the east and Múlakvísl in the west. Both rivers carry water from the Mýrdalsjökull glacier to the sea. Mýrdalssandur has a -long coast line, including Kötlutangi , the southernmost point of the island of Iceland. The Ring Road crosses this flat surface on . Development The outwash plain was built by the numerous jökulhlaups of the Mýrdalsjökull. The last large jökulhlaup was due to an explosive eruption of the Katla volcano under the glacier in 1918, and the water volume at the peak of the jökulhlaup was estimated to be around 200,000 - 300,000 m³/s. History of settlements South of the road rises Hjörleifshöfði to a height of . The mountain is named after Hjörleifr Hróðmarsson. He was the first settler to come to Iceland with Ingólfr Arnarson. In the Middle Ages there was a fishing lake called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hjörleifshöfði
Hjörleifshöfði () is a -high inselberg in southern Iceland. It consists of palagonite. The mountain is located on the Mýrdalssandur outwash plain about east of Vík í Mýrdal, and was an island in the Atlantic Ocean. Name The name was given to the mountain by one of the first legendary settlers mentioned in the ''Landnámabók''. According to this, Hjörleifr Hróðmarsson was the brother-in-law of Ingólfur Arnarson, Iceland's first official settler. He settled at Hjörleifshöfði towards the end of the ninth century. There, however, he was slain by his slaves. The slaves fled to Vestmannaeyjar, where Ingólfur took his revenge for his friend and slew them. On the top of the mountain is a mound called Hjörleifshaugur , where Hjörleifr is said to be buried. Geology The mountain is of volcanic origin but was covered by ice or seawater at the time of its formation, so it has a similar past as the nearby larger Hafursey mountain. Then it was an island surrounded by sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Route 1 (Iceland)
Route 1 or the Ring Road ( or ) is a National road (Iceland), national road in Iceland that circles the entire country. As a major Trunk road, trunk route, it is considered to be the most important piece of transport infrastructure in Iceland as it connects the majority of towns together in the most densely populated areas of the country. Economically, it carries a large proportion of goods traffic as well as Tourism, tourist traffic. The total length of the road is , making it the longest ring road in Europe. The road was completed in 1974, coinciding with the 1,100th anniversary of Settlement of Iceland, the country's settlement when the longest bridge in Iceland, crossing the Skeiðará river in the southeast, was opened. Previously, vehicles intending to travel between southern settlements, e.g. Vík to Höfn, had to travel north of the country through Akureyri, making the opening a major transport improvement to the country. Many popular tourist attractions in Iceland, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Rivers Of Iceland
On an island like Iceland, the rivers are short in length. None of the rivers are important as a means of navigation due to the impracticality of settlements in the Highlands of Iceland where they originate. South * Hvítá * Krossá * Kúðafljót * Markarfljót * Mustafl *Ölfusá (the Icelandic river with the greatest flow) * Rangá *Skaftá *Skeiðará * Skógá * Sog *Þjórsá (the longest river in Iceland, 230 km) * Tungnaá West *Fossá * Hvítá * Kjarrá–Thervá * Norðurá Westfjords * Dynjandi * Kolbeinsá * Staðará North *Blanda * Eyjafjarðará * Eystri Jökulsá * Fnjóská * Glerá * Grafará * Gönguskarðsá * Heiðará *Héraðsvötn * Hjaltadalsá * Hofsá (Skagafjörður) * Hofsá (Vesturdalur) * Hörgá * Jökulsá á Fjöllum * Kolka (Kolbeinsdalsá) * Laxá * Norðurá * Sauðá *Skjálfandafljót * Svartá * Sæmundará * Vatnsdalsá East * Hamarsá * Hofsá * Jökulsá á Dal * Jökulsá í Fljótsdal * Jökulsá í Lóni *Laga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kettle (landform)
A kettle (also known as a kettle hole, kettlehole, or pothole) is a depression or hole in an outwash plain formed by retreating glaciers or draining floodwaters. The kettles are formed as a result of blocks of dead ice left behind by retreating glaciers, which become surrounded by sediment deposited by meltwater streams as there is increased friction. The ice becomes buried in the sediment and when the ice melts, a depression is left called a kettle hole, creating a dimpled appearance on the outwash plain. Lakes often fill these kettles; these are called kettle hole lakes. Another source is the sudden drainage of an ice-dammed lake and when the block melts, the hole it leaves behind is a kettle. As the ice melts, ramparts can form around the edge of the kettle hole. The lakes that fill these holes are seldom more than deep and eventually fill with sediment. In acidic conditions, a kettle bog may form but in alkaline conditions, it will be Mire, kettle peatland. Overview Kettles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the structural integrity of such a chamber, greatly diminishing its capacity to support its own roof and any substrate or rock resting above. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface (from one to dozens of kilometers in diameter). Although sometimes described as a Volcanic crater, crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur over the course of a century, the formation of a caldera is a rare event, occurring only a few times within a given window of 100 years. Only eight caldera-forming collapses are known to have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fissure Vent
A fissure vent, also known as a volcanic fissure, eruption fissure or simply a fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is often a few metres wide and may be many kilometres long. Fissure vents can cause large flood basalts which run first in lava channels and later in lava tubes. After some time, the eruption tends to become focused at one or more spatter cones. Volcanic cones and their craters that are aligned along a fissure form a crater row. Small fissure vents may not be easily discernible from the air, but the crater rows (see Laki) or the canyons (see Eldgjá) built up by some of them are. The dikes that feed fissures reach the surface from depths of a few kilometers and connect them to deeper magma reservoirs, often under volcanic centers. Fissures are usually found in or along rifts and rift zones, such as Iceland and the East African Rift. Fissure vents are often part of the structu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jökulhlaup
A jökulhlaup ( ) (literally "glacial run") is a type of glacial outburst flood. It is an Icelandic term that has been adopted in glaciological terminology in many languages. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland, which are triggered by geothermal heating and occasionally by a volcanic subglacial eruption, but it is now used to describe any large and abrupt release of water from a subglacial or proglacial lake/reservoir. Since jökulhlaups emerge from hydrostatically sealed lakes with floating levels far above the threshold, their peak discharge can be much larger than that of a marginal or extra-marginal lake burst. The hydrograph of a jökulhlaup from Vatnajökull typically either climbs over a period of weeks with the largest flow near the end, or it climbs much faster during the course of some hours. These patterns are suggested to reflect channel melting, and sheet flow under the front, respectively. Similar p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentation
Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the forces acting on them: these forces can be due to gravity, centrifugal acceleration, or electromagnetism. Settling is the falling of suspended particles through the liquid, whereas sedimentation is the final result of the settling process. In geology, sedimentation is the deposition of sediments which results in the formation of sedimentary rock. The term is broadly applied to the entire range of processes that result in the formation of sedimentary rock, from initial erosion through sediment transport and settling to the lithification of the sediments. However, the strict geological definition of sedimentation is the mechanical deposition of sediment particles from an initial suspension in air or water. Sedimentation may pertain to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
