Sturkell, E. Vogfjord , Sigurlaug Hjaltadottir , Gunnar B. Gudmundsson , Matthew J. Large explosions from the summit crater; ash plumes close airspace in Europe.
After a short hiatus in eruptive activity, an explosive eruptive phase began on 14 April under the ice-covered central summit caldera. The resulting plume caused an unprecedented disruption of air traffic and closure of airspace over northern and central Europe. In the early morning of 14 April, the ash-loaded eruption plume rose to more than 8 km altitude and blew E.
The eruption plume reached mainland Europe on 15 April, triggering the closure of airspace over large areas. On 16 April some variability occurred in seismic tremor and tephra generation, but overall the eruptive pace remained stable and large closures of airspace continued.
The IES estimated the amount of erupted material during the first 72 hours of the eruption at the summit caldera April Erupted products consisted of fragmental material, the majority being fine-grained airborne tephra.
On 17 April the ash plume rose to over 8 km altitude, blowing first to the E, and then, after about that day, blowing to the S. Ash fell around the volcano and there were at least lightning strikes in vicinity of the eruption. When ash emissions on 17 April figure 12 blew S they created an optically thicker band of ash that appeared to be surrounded by a much wider, less optically dense plume figure NASA analysts determined that the ash plumes were at two different altitudes, the narrow, more concentrated plume was above the more diffuse cloud, casting a shadow on the ash below.
They said that according to the Icelandic Met Office, the upper parts of 17 April ash puffs reached 4. The 17 April example illustrates the difficulty of estimating the critical 'source terms' boundary conditions for modeling ash plume dispersal. Such models, which are regularly run by groups such as VAACs, volcano observatories, and their associated agencies, help assess where plumes might go in conditions such as darkness and overcast weather.
After about on 18 April, tremor intensified beyond levels maintained since 16 April. Daily solutions from continuous, second GPS stations operated by IMO and IES, revealed centimeter-scale horizontal movements toward the center of the volcano, with some stations also registering centimeter-scale vertical elevation decreases. Tremor with a dominant frequency of 0. Following an initial period of glacial flooding on April, relatively little water drained from the ice cap's N flank. On 19 April the plume rose only m above the volcano's 1.
Later in the afternoon reports indicated maximum plume height around 4. Samples collected 19 April show the same composition as early in the explosive phase, but the fluorine content was higher. Tephra deposited next to the craters was m thick. Analogous conditions continued to exist for the following week. Although there had been magma spatter at the vent area by 20 April, no significant lava flow had yet been detected. Heavy sound blasts were heard nearby, especially S and E of the mountain.
Radar images acquired that day by the Icelandic Coast Guard showed no changes in the size of the cauldron since 19 April. Latest results from GPS stations showed deflation. On 21 April, the eruption continued with less explosive activity.
The northernmost one of two main craters in the summit caldera was active, and phreatomagmatic explosions occurred with some lava spatter at craters. Lava flows towards the N were thought to have begun around noon on 21 April. Beginning about 24 April the IES website contained detailed daily status reports of the eruption. Over the next few days there was little change, with the N crater remaining active, generating mild explosive activity and spatter. Steam plumes were rising where the N-flowing lava met ice.
The eruption site was seen clearly during an overflight on 27 April. The eruptive activity in the N ice cauldron was seen to be similar to conditions during the preceding four days, but a new crater had formed in the cauldron's SW corner. Erupted material continued to accumulate on the flanks of the crater. Spatter escaped the vent, reaching heights of m.
Unstable plumes of ash rose regularly from the vent. After an slight decrease in explosive activity early in May, activity then increased somewhat. The eruption was mixed, with the lava-producing phase being larger than the explosive phase. During this time, the plume was darker and wider than in the preceding week. Near-source tephra fall-out increased.
On 4 May a flight by the Icelandic Coast Guard showed that the crater continued buildup in the northern-most ice cauldron. Lava flowed N and spread at an elevation of m. Increased seismicity up to 13 May suggested that new material was intruding from depth, and GPS observations indicated inflation.
Little change in activity was observed during May. Tephra fallout was detected mainly to the NE, with some reaching the coast. Some tephra dispersed towards the W in the afternoon. By May only a weak plume rose from the W part of the crater; both explosions and lava flows from the crater were absent. During May there was no apparent eruptive activity, though there was still a considerable amount of steam coming from the crater.
Aerial observers on 25 May figure 14 saw blue smog sulfuric gases and smelled sulfur. Scientists who went to the crater on 25 May saw a small blast of ash, but mostly steam. Intense steam rose from the craters, with occasional small ashy explosions. Noise of intense boiling and or degassing came from the craters. Visibility to the bottom was limited due to steam. A strong smell of sulfur came from around the craters. Volcanic tremor was still higher than before the eruption, being rather steady since 22 May, but small pulses, mostly on the lowest frequency, were detected.
Several small and shallow earthquakes under the volcano occurred on a daily basis. No significant GPS deformation was measured. There was still a considerable amount of steam coming from the crater. Recent precursory intrusions. According to Sturkell and others , "In , and again in , magma intrusion was detected under the southern slopes of Eyjafjallajokull.
These intrusions had their center of uplift approximately 4 km southeast of the summit crater of the volcano and were associated with considerable seismic activity. After the intrusion event in , crustal deformation and earthquake activity at Eyjafjallajokull have remained low.
Aviation impacts. According to Wall and Flottau , more than , flights were canceled after the ash plume caused aviation authorities in many parts of Europe to close their airspace for several days.
Wall, Flottau, and Mecham noted the difficulty if assessing the risk of flying through volcanic ash plumes which can have varying particulate concenrations and compositions. Routes of several FAF aircraft figure 15 suggest that the flight distances were on the order of a few hundred kilometers.
The Flightglobal website reported the FAF released images showing the effects of volcanic dust ingestion from inside the engines of a jet fighter that flew through the ash cloud on the morning of 15 April. One aircraft engine showed melted ash clearly visible on an interior surface.
Another jet trainer flew through the plume carrying an air sampling pod to collect dust from the atmosphere at various altitudes, however the measurements have yet to be reported.
Einarsson, P. This compilation of synonyms and subsidiary features may not be comprehensive. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.
It consists of an elongated ice-covered stratovolcano with a 2. Fissure-fed lava flows occur on both the E and W flanks, but are more prominent on the western side. Although the volcano has erupted during historical time, it has been less active than other volcanoes of Iceland's eastern volcanic zone, and relatively few Holocene lava flows are known.
An intrusion beneath the S flank from July-December was accompanied by increased seismic activity. The last historical activity prior to an eruption in produced intermediate-to-silicic tephra from the central caldera during December to January The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Volcanic hazards in Iceland. Jokull , Post-Miocene Volcanoes of the World.
Jakobsson S P, Petrology of recent basalts of the eastern volcanic zone, Iceland. Acta Nat Islandica , Johannesson H, The endless lavas at the foot of Eyjafjoll and glaciers of the last glaciation. Jokull , in Icelandic with English summary. Geological map of Iceland, sheet 6, south Iceland.
Oskarsson B V, Unpublished Master's thesis , Univ Iceland, p. Pedersen R, Sigmundsson F, Temporal development of the intrusive episode in the Eyjafjallajokull volcano, Iceland, derived from InSAR images. Bull Volcanol , Steinthorsson S, et al.
Catalog of Active Volcanoes of the World - Iceland. Unpublished manuscript. May summit eruption, indicating gradual deflation of a source distinct from the pre-eruptive inflation source. Black orthogonal arrows show the satellite flight path and look direction. One colour fringe corresponds to line-of-sight LOS change of Black dots show earthquake epicentres for the corresponding period. Background is shaded topography. Thick lines below indicate the time span of the interferograms.
Red stars and triangles same as in Fig. Hooper, T. Pedersen, M. Roberts, N. Oskarsson, A. Auriac, J. Decriem, P. Einarsson, H. Geirsson, M. Hensch, B. Ofeigsson, E. Sturkell, H. Feigl, Nature , , Remarks: GPS and InSAR data reveal a pre-eruptive stage of inflation due to a complicated time-evolving magma intrusion that produced variable and high rates of deformation, in particular after 4 March.
One of the nine interferograms selected for modeling the intrusive episode. Incoherent areas are masked. Amplitude image in background. The area corresponds to Fig. The time span insets show the relation to the period s of elevated seismic activity Dark gray main seismic period; Light gray secondary seismic period.
For details on dates please refer to Table 2. One full color cycle corresponds to a change in range of 2. Einarsson, F. Sigmundsson, S. Hreinsdottir, and H. Geophysical Research Letters , 30, Remarks: Deformation at Eyjafjallajokull is accompanied by an earthquake swarm in June and can be modeled with a horizontal sill intrusion.
All images cover the area shown in Figure 1B. Glacier outlined in black. Details on image-pairs in Table 1; f Fringe pattern predicted by variable opening sill model. Dashed line shows outline of uniform sill plane. Green star: optimal Mogi source. Grey circles: best micro-earthquake locations from the swarm; g Variable sill opening.
The three minor areas of opening disconnected from the main sill are artifacts due to atmospheric noise in the data. Sigmundsson,, Geophysical Research Letters , 31, L The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full dpi map. Very small-scale maps such as world maps are not included.
The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email. Catalog number links will open a window with more information. Figure Courtesy of USGS. Stars indicate eruptive sites map scale at top left.
The map includes a small slice of the Atlantic ocean along the lower left-hand margin. Revised from a map by Sigmundsson and others The scene helps explain the high degree of water and ice interaction with the erupting lavas. Snow had melted from numerous ash and lava-covered surfaces black areas. Although portions of the crater emitted steam, evidence of substantial ongoing lava emissions were absent at this point in time.
Courtesy of Sigmundsson and others The left-hand graphic is a true-color RGB red-green-blue composite, and the right-hand image is a false-color composite of Bands 32, 31, and 29 12, 11, and 8. These data were processed with the decorrelation stretch D-stretch , a technique for enhancing spectral contrast based on principal components analysis.
In this rendition the ash plume appears red and the ice-rich clouds appear blue. The D-stretch was based on scene statistics and was intended to be a quick method for discriminating material that may be volcanic in origin. Courtesy of Vincent J. Marked arrows on the map give locations of labeled photos A-E taken 18 September A Fresh lava darker seen looking N. In the distance appear fresh black lava flows, some portions of which formed the lava falls down the valley walls.
B View showing the elongate ridge as seen from the upslope perspective people in the distance for scale. This photo was taken with a flash, otherwise the fissure walls would have been very dark. D The fracture indicated on the map as it appeared near the rim of the ridge of newly erupted lava. E The same fracture seen in D from another perspective.
Courtesy of John and Ludmilla Eichelberger. Information is preliminary and subject to change. Figure 1. Index map showing some eruptive centers is from Laursen Base map courtesy of IMO. The main outlet glaciers are to the north: Gigjokull that flows into Lonid, and Steinholtsjokull which flows into Steinholtslon. The mountain itself stands 1, metres 5, ft at its highest point. It has a crater 3—4 kilometres 1. On March 20, Eyjafjallajokull began spewing molten lava in an uninhabited area in south Iceland , after being dormant for years.
On April 14th, , after a brief intermission, the volcano resumed erupting from the top crater in the center of the glacier. The renewed eruption caused massive flooding, which required an evacuation of people. This second eruption threw volcanic ash several kilometers up in the atmosphere. The ash plume could be seen from miles away. That led to air traffic disruption in North-West Europe. The disruption lasted for six days, from April 15th to April 21st, that stranded thousands of travelers.
It happened again in May, which resulted in the closure of airspace over many parts of Europe. The eruption also created electrical storms. The volcano continued to have several earthquakes daily, with volcanologists watching the mountain closely. Today the aftermath of the volcanic eruption can be seen in Thorsmork Glacier Valley, the natural oasis that lies just behind the volcano.
You can also see a part of the ice cap is still covered in ash, though that is slowly disappearing under layers of snow. Perhaps you would like to go on a snowmobile tour on the ice cap and see the crater, which also offers you a great view of southern part of Iceland. Eyjafjallajokull is a strato volcano.
It is a conical volcano built by many layers of hardened lava, tephra, pumice and volcanic ash. Strata volcanoes are among the most common volcanoes.
Due to the glacier on top of Eyjafjallajokull eruptions are explosive and contain much ash. A large magma chamber under the mountain feeds Eyjafjallajokull. The chamber derives magma from the tectonic divergence of the Mid-Atlantic ridge. You can still see the effects of the eruption in the surrounding area, including layers of ash and newly-formed craters.
The Eyjafjallajokull eruption did not harm life in Iceland. Thorsmork Volcano Hike 14 reviews. Availability Apr - Oct. Duration hours. Departs From Reykjavik. Level Challenging. Minimum age 14 years.
Ratio Pick Up Yes. Meet on Location No. View Tour. Best Seller. Eyjafjallajokull Snowmobiling Availability All Year. Level Easy. Minimum age 5 years. Meet on Location Yes. Pick Up No. Super Jeep Tour. Duration 5 hours. Minimum age No min age. Explore a World-famous Volcano in a Super Jeep. What type of volcano is Eyjafjallajokull? From the 18th of April to the 4th of May: Now a combination of an explosive eruption and flowing lava went on.
From the 5th of May to the 17th of May: The eruption has started to cool down, eruptions were happening less frequently and no new lava was flowing.
From the 18th of May to the 22nd of May: Decreased upstream of magma and the smoke coming from the eruption was getting a lot smaller. See More. Here are videos on how NOT:.
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