According to the team, their results show that gravity is the primary force causing this flank of the volcano to move. This makes sense: Rising magma can inflate parts of the mountain, adding extra weight to sections of it and causing structural weaknesses to appear.
This activity coincided with the eight-day movement of a local fault. The team agrees that rising magma does play a role, because other flank accelerations match up nicely with unambiguous intrusions of new molten material. But the fact that such huge deformations are also occurring far from the magma-dominated summit suggests that gravity is the star of the show—a notion shared by other research groups.
Their data indicated that, from to , Etna moved toward the Ionian Sea in a southeasterly direction at a rate of 0. These researchers also suspect that gravity is the driving force, pushing Etna along on a layer of loosely packed sediments. The April study suggested that the entire volcano was moving, but the new paper only looked at the southeastern flank.
Both factors are also connected, with gravitationally driven flank movements allowing magmatic intrusions to take place. No wonder, then, that Etna is one of the most heavily monitored volcanoes on Earth. All rights reserved. A Yosemite Icon Half Dome, here in , has long been an iconic feature of Yosemite, which was established as a national park in thanks largely to efforts by explorer and naturalist John Muir.
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A quake triggered by Italy's Mount Etna volcano has jolted eastern Sicily, slightly injuring 10 people and prompting frightened Italian villagers to flee their homes. The Mount Etna observatory says lava and ash are spewing from a new fracture on the active Sicilian volcano amid an unusually high level of seismic activity. Explore further. This document is subject to copyright.
Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Global consensus needed to develop climate risk disclosures for companies 15 hours ago. Ash and lapilli fell onto the E flank of the volcano, near an area affected by the tephra fall on the previous day.
A few hours later images revealed a new lava flow from VOR traveling W. Eruptive activity continued at least through , though the volcanic tremor amplitude had diminished. At on 23 February an explosion at Northeast Crater NEC ejected incandescent tephra several tens of meters above the crater rim, and produced a dark ash plume that drifted NE. A camera recorded lightning flashes in the plume. Weak ash emission rose from the crater during the rest of the morning.
During December Strombolian activity was detected at NEC, with a few ejected incandescence bombs falling onto the outer flank and abundant ash emissions. Activity gradually diminished over a few days. The emissions ceased in the afternoon; very minor and sporadic explosions continued from the same vent during the following days. Seismicity had significantly decreased. INGV reported that after a progressive intensification of activity during the evening of 2 December, an eruption at Etna's Voragine Crater peaked between and on 3 December.
During the peak period sustained lava fountains rose over 1 km above the crater with some jets of hot material rising 3 km high. Activity had almost ceased by dawn. This event was among the largest in the last 20 years, similar to large events occurring at the same crater on 22 July and 4 September At about on 4 December renewed activity at Voragine Crater was characterized by tall lava fountains and an ash plume that rose km high.
The ash plume had a mushrooming top and produced deposits of coarse-grained pyroclastic material on the upper SW flank above 2 km elevation. Ashfall was reported in Giarre-Zafferana Etnea on the E flank. The activity was accompanied by frequent ash emissions from a new pit crater that had recently opened on the upper E flank of the New Southeast Crater NSEC cone. Two more events occurred at Voragine Crater during December, between and on 4 December and and on 5 December, again producing tall lava fountains and many-kilometer-high ash plumes.
During the evening of 5 December activity at Voragine Crater progressively diminished. Between and on 6 December surveillance cameras recorded the onset of vigorous Strombolian activity from the vent on the E flank of the NSEC cone. Repeated collapses of both old and new material from the cone's flank generated hot avalanches that traveled a few hundred meters E towards the Valle del Bove.
Ongoing effusive activity through the day produced two lava flows; one advanced NE for less than 1 km and the other advanced E. Strombolian activity continued through the evening.
During the early morning hours of 8 December Strombolian activity progressively diminished and then ended. Later that afternoon weak Strombolian activity and ash emission were observed at the Northeast Crater. At on 13 May a series of small collapses accompanied the opening of three vents, along a fracture oriented E-W, below the E rim of NSEC, one of which effused a small lava flow. At a fracture at the vent propagated m from the rim down the cone within 10 minutes.
This event was accompanied by collapses, along with reddish ash ejection onto the summit area and the high S flank. Strombolian activity increased that night and was characterized by almost continuous Strombolian explosions, sometimes accompanied by ash emissions. This activity continued during May. Ash plumes rose a few hundred meters and dispersed with the wind; minor ashfall was reported in areas from the S to the NE.
A single lava flow traveled NE towards Mt. Rittman, and then E towards Mt. Simone where it formed two branches. Activity decreased on 15 May and ceased on 16 May. This activity was preceded by a sudden increase in tremor amplitude and intense degassing during May; visible activity did not accompany the episode, and after a few days tremor returned to normal levels.
Resulting ash puffs rose a few hundred meters above the crater and dispersed. Poor meteorological conditions prevented views of the summit area during the first 36 hours of the eruption. During improved viewing conditions on the evening of 1 February, volcanologists observed Strombolian activity from a single vent in the saddle between the cones of the Southeast Crater SEC.
Explosions occurred every few seconds and ejected incandescent bombs m high. At the same time a vent at the base of the southern SEC cone issued a lava flow that traveled 2 km S, dividing into two branches. At dawn on 2 February the Strombolian activity produced a dense ash cloud that drifted E.
At about emissions stopped and volcanic tremor suddenly decreased. The next day occasionally pulsating ash emissions rose from Northeast Crater and drifted SE. Ash emissions continued through 17 January; cloud cover prevented observations of the summit area on 18 January.
INGV reported that at night during January the frequency of Strombolian explosions at Etna's Voragine Crater decreased; however, some of the explosions ejected incandescent pyroclastic material outside of the crater and onto the W and SW flanks.
On 7 January many of the small explosions generated brown ash plumes that rose a few hundred meters above Etna's summit and quickly dissipated. Strombolian activity increased on 8 January, possibly from two vents within the crater.
Pyroclastic material continued to be ejected out of the crater. Early on 9 January Strombolian activity again decreased and gave way to ash emissions that rose several hundred meters. Ash emissions continued the next morning, decreased, and had almost completely ceased by late morning. Ash emissions resumed in the afternoon and were sometimes accompanied by Strombolian explosions. Ash emissions on 13 January were continuous in the morning but then decreased in frequency by the afternoon.
During the night on 1 and 2 January cameras recorded intermittent flashes from Voragine Crater one of four summit craters , indicating Strombolian activity there for the first time in nearly two years.
On the evening of 3 January explosions ejected incandescent material m above the crater rim. Inclement weather prevented observations of the summit area so the erupting crater was not identifiable. Tremor began to decrease at , and indicated that the eruption was over at During some nights small Strombolian explosions ejected incandescent material a few tens of meters above the crater rim.
Lava continued to flow about 3 km NE towards Monte Simone. On 9 August INGV reported that volcanic tremor decreased and an ash plume rose to 1 km above the July 25 area of Etna and returned to strong Strombolian activity in the evening. Strombolian activity increased at New Southeast Crater that was accompanied by small emissions of black ash that remained within the crater. The vent was located around 3,, m elevation. Weak and sporadic strombolian explosions and small ash emissions were observed during July from New SE Crater, but by 11 July this activity had ceased.
Activity from the new fissure continued through 11 July with frequent strombolian explosions that were audible in nearby towns. Some explosions ejected incandescent pyroclastic material a few tens of meters above the crater rim that occasionally fell onto the outer flanks. On 14 June a new eruptive episode began within the NSEC, beginning with near-continuous Strombolian explosions and lava fountaining.
Fine ash emissions were concurrent with lava that began to overflow the edge of the SE crater, forming a flow that continued downhill on the W wall of Valle del Bove. During the morning of 15 June the overflowing lava followed the fissure that had been formed on 28 November A spatter cone also formed in the E sector of the cone.
During June volcanic tremor increased sharply and remained at a medium-high level until 18 June when it returned to normal levels. INGV noted that this activity was similar to the episode of effusive lava emissions observed during and December in terms of duration and intensity. Some explosions ejected incandescent pyroclastic material a few tens of meters above the crater rim that rarely fell onto the outer flanks. Some explosions ejected incandescent pyroclastic material out of the crater and onto the upper S and SE flanks of the cone.
A few small collapses occurred on the cone's unstable E flank. The frequency and intensity of Strombolian explosions slightly increased late in the evening on 30 April. Degassing at the Northeast Crater also increased and thermal anomalies were detected by a camera. Weak Strombolian activity continued to be detected through 1 May. Strombolian activity gradually intensified during the evening of 2 April and then decreased the next morning.
Some collapses from the E flank of the cone were also observed that morning. Poor weather conditions prevented views of Etna for a few days, but by 7 April the lava flows had ceased and Strombolian activity had sharply declined. No activity was observed on 8 April. Lava emissions from the lower side of the NSEC significantly decreased; on the evening of 28 March a small lava flow continued to advance but had stopped and was cooling the next day. Strombolian activity intensified during March, producing more ash, and then decreased; no ash was emitted on 23 March.
Lava flows originating from a vent on the upper wall traveled towards the upper part of the W wall of the Valle del Bove and also NE in the direction of Monte Simone. Lava flows originating from a vent on the upper wall traveled towards the upper part of the W wall of the Valle del Bove. After several days of lava emissions from a vent on the lower part of the NSEC cone, during March lava flows originated only from a higher vent and traveled 1.
On 8 March sporadic emissions of hot material with small amounts of volcanic ash originated from Bocca Nuova. An unstable part of the lower E flank of the cone that collapsed on 11 February continued to produce small collapses with reddish ash clouds. Lava continued to flow from a vent on the lower part of the NSEC cone to the W wall of the Valle del Bove, and during March the flows reached the base of the wall.
An unstable part of the lower E flank of the cone that collapsed on 11 February continued to produce small collapses with reddish ash clouds, and thermal anomalies.
An unstable part of the lower E flank of the cone that collapsed on 11 February continued to produce small collapses and reddish ash clouds. Lava continued to flow from the cone towards the Valle del Bove, and by nightfall had reached the base of the steep W wall of the valley, then advanced on the flat land to the N of Mount Centenarians.
Strombolian activity continued during February. Lava emissions declined, but produced lava flows a few hundred meters long. At on 15 February an explosion generated a vapor-and-ash plume, and was then followed by more explosions from the same area. The flow traveled m towards the W wall of the Valle del Bove, and remained active the next day.
During February Strombolian activity continued to produce small quantities of ash. Lava continued to flow from the vent at the base of the cone. The lava flows reached the base of the W slope of the Valle del Bove. On 6 February ash emissions ceased and small Strombolian explosions ejected incandescent pyroclastic material m above the crater. On 7 February Strombolian explosions ejected material onto the flanks of the cone, and the next day ash puffs were observed. During February activity continued to be characterized by Strombolian activity, periodic ash emissions, and advancing lava flows.
At on 11 February a large quantity of reddish brown ash emitted from an area near the vents formed a very dense hot flow which quickly reached the base of the W wall of the Valle del Bove. Reddish brown ash emissions continued after the event. Weak and sporadic Strombolian explosions were detected at night, but then the thermal cameras recorded no anomalies associated with Strombolian activity.
Lava flows from two vents at the base of the NSEC cone continued to effuse at a very low rate. Weather conditions almost entirely prevented observations of Etna from the morning of 30 January until the evening of 3 February. Late on 3 February observers noted that the lava flow remained active and was several hundred meters long. Almost continuous ash emissions from NSEC began at about on 4 February and continued into the night; about ash puffs were separated by steam emissions.
Ash plumes drifted E. After sunset jets of hot material were observed rising m above the crater rim. At the ash emissions and injection of incandescent material ceased, but the lava flow continued and reached 1 km long. Strong degassing continued at least through 22 January.
Some explosions generated very small ash emissions that barely rose above the crater rim. Late on 22 January a small lava flow from the vent on the high E flank of the NSEC cone traveled a few hundred meters in a few hours. Strombolian explosions ejected incandescent pyroclastic material onto the cone flanks. The frequency and intensity of the explosions decreased early on 23 January, and the lava flow stopped advancing.
Weak Strombolian activity and the advancing lava flow continued during January, although on 25 January the amount of ash produced by the Strombolian activity increased. On 26 January an ash plume drifted E. By evening the intensity of the Strombolian activity as well as the amount of ash in the emissions decreased. The lava flow was 4 km long. Volcanic tremor amplitude remained at low levels. On 3 January staff doing field work noted that the effusive activity had stopped.
During the early morning hours on 29 December a camera recorded weak and sporadic incandescence from NSEC. Strong pulsating degassing also occurred at Northeast Crater. After the explosion mild Strombolian activity continued and then progressively intensified in the evening. Frequent powerful explosions from two vents located within the crater were audible in a vast sector around the volcano. Diffuse ash plumes drifted NE. Contemporaneously, two lava flows are active, one from a vent on the E flank of the NSEC cone, and the second, fed directly from the crater, traveled down the NE flank of the cone.
Intermittent ash emission gradually turned into Strombolian activity. After the activity intensified; small ash puffs were produced and Strombolian explosions ejected incandescent pyroclastics onto the flanks of the cone. Over the next few hours activity continued to intensify and a diffuse ash plume drifted ESE. At lava overflowed the SE crater rim and flowed towards the Valle del Bove.
During the night explosive activity continued to intensify, and by on 15 December Strombolian activity was intense and virtually continuous. After explosive activity started to diminish, and at the volcanic tremor amplitude and the intensity and frequency of Strombolian explosions showed a sharp drop. Explosive activity continued to produce copious amounts of ash until about According to a news article, the ash emissions caused the cancellation of more than 20 flights in and out of the Catania airport.
At and two vents opened within the deep trench cutting the SE flank of the NSEC cone where lava was still flowing from the crater since the previous evening , the first just a few tens of meters below the crater rim, the second about m further downslope. Both vents initially produced lava fountains for a few minutes, with jets a few tens of meters high, and then produced lava flows that descended through the trench. Between on 15 December and the morning of 16 December ash emission varied in frequency and intensity, related to variations in the intensity of the Strombolian activity at NSEC.
During the afternoon and evening of 15 December explosive activity lasted a few to a few tens of minutes and Strombolian activity became significantly more intense or passed into pulsating, low lava fountains. The more intense periods produced greater amounts of ash leading to ashfall in populated areas on the E and SE flank, from the Milo-Zafferana area toward the Ionian coast. At night during December lava flows continued to flow towards the Valle del Bove.
On 15 December small and periodic ash emissions also occurred from Northeast Crater. Small thermal anomalies detected with a thermal camera were detected during December.
Strombolian activity at the NSEC continued through 16 December at a slowly decreasing rate and with numerous minor intensifications that generated diluted ash plumes. Lava effusion also gradually diminished, but at about on 16 December, a short fissure opened on the lower NE flank of the NSEC cone, producing a small lava flow which advanced a few hundred meters. Explosive activity finally ceased around midnight on 17 December. Very slow lava effusion continued, at a gradually decreasing rate, from the fissure on the NE flank of the NSEC cone, through the night of December.
Weather clouds prevented observations of the event. Vigorous Strombolian activity on 2 December produced a plume comprised mostly of gas drifting N. The activity intensified during the evening and evolved into a paroxysmal event that finished by The event was characterized by tall lava fountains, lava flows, and a plume laden with pyroclastic material that drifted NNW and deposited ash and lapilli in that area.
The next day sporadic explosions continued, inclement weather however prevented visual observations. The episode was characterized by a rapid evolution from Strombolian activity to lava fountains, an ash plume that rose several kilometers and drifted NE, and lava flows that were significantly less extensive than those emitted during the November paroxysm. INGV-Osservatorio Etneo staff visited the area the next day and noted that explosions were heard one to three times per minute, and during times of good visibility no pyroclastic material was ejected.
Sporadic ejections of incandescent pyroclastics were observed after nightfall. Early on 16 November Strombolian activity gradually intensified; however, only pulsating puffs of vapor, but no ash, were produced. On 17 November a new paroxysmal eruptive episode was characterized by violent Strombolian activity and pulsating lava fountains, emission of lava flows that traveled S, ESE, and NE, and the formation of an eruption column charged with pyroclastic material that drifted NE.
The episode ended with a long series of powerful explosions and loud bangs heard tens of kilometers away. Strombolian activity continued until the late evening; after nightfall, a small lava flow issued from an effusive vent located on the lower E flank of the NSEC cone. During November several phases of frequent explosions produced ash puffs visible during the daytime and ejected incandescent material from Strombolian activity was visible at night.
On 8 November the explosions occurred at intervals of several hours, producing small ash plumes that rose a few hundred meters above the summit and drifted ENE.
A culminating phase of lava fountains, ash emissions, and lava flows began at on 11 November, after about 10 hours of gradually intensifying Strombolian activity. Weather conditions prevented visual observations, but a strong increase in the volcanic tremor amplitude was detected.
The phase of maximum intensity lasted about 7. Ash and lapilli fell in areas E and NE. Vigorous Strombolian activity continued, with explosions at intervals of minutes, which launched incandescent material as high as m above the crater rim.
At night during November Strombolian activity ceased and the lava flows were no longer active. A brief glow seen on surveillance cameras was followed by ash emissions. The event was accompanied by a strong seismic signal detected by summit seismic stations. Poor weather prevented additional observations. A gas plume laden with pyroclastic material rose several kilometers above the summit and drifted SW, affecting population centers as far as the Caltanissetta area.
According to a news article a representative from Catania airport noted that the eruption caused the closure of nearby airspace before dawn through the early morning. Lava emitted from the saddle between the two cones of the Southeast Crater advanced S, destroying two wooden shacks at Torre del Filosofo. Another smaller lava flow descended the SE flank of the NSEC cone, partially filling the deep collapse scar formed during the 27 April paroxysm.
At vigorous ash emissions from the Northeast Crater formed a dark brown plume that rose 1 km; ash emissions from that crater continued through late evening. Lava fountaining from NSEC continued through the late morning and was then followed by a long series of powerful explosions audible to many tens of kilometers away.
Strombolian explosions occurred in the late evening. Lava flows continued to advance the next day. Sezione di Catania - Osservatorio Etneo reported that a series of small and sporadic ash emissions from Etna's New Southeast Crater NSEC began during the morning of 3 September, marking the end of four months of complete quiescence.
At daybreak small ash puffs were emitted once or twice per hour. The same morning intense incandescence emanated from Bocca Nuova. The report stated that since early May only degassing from the summit craters was noted, along with usual bangs and rumblings from deep within the conduit of the Northeast Crater NEC , which during the past few weeks had become more continuous and louder.
Activity increased on 21 April and was characterized by Strombolian explosions and frequent ash emissions. Eruptive activity and the volcanic tremor amplitude gradually increased in the evening of 26 April. Activity increased on 16 April with ejected incandescent tephra and small ash puffs from a vent inside NSEC, followed by weak Strombolian explosions.
Strombolian explosions became more frequent and intense on the morning of 18 April and then were almost continuous by During the next two hours lava fountains developed and a dense plume drifted SSW. Ash and lapilli fell in between the villages of Ragalna, Belper, and Paterno, as well as the tourist area "Etna Sud. Three lava flows were produced; the largest flowed through the deep notch in the SE rim of the crater and traveled 4 km towards the Valle del Bove.
The interaction of the lava with snow led to rapid melting, generating small lahars. The two other lava flows originated in the saddle between the two SEC cones; one traveled N and the other S.
After the lava fountains ceased, strong explosions were heard the rest of the day. On 19 April explosions produced little puffs of ash and ejected hot tephra.
The twelfth episode occurred two days later during the late afternoon of 20 April. Intermittent explosions ejected incandescent tephra and generated small ash puffs on 19 April. During the evening a large dark plume rose from NSEC, and sporadic Strombolian explosions were observed. The explosive activity ceased in the late evening, but shortly afterwards the lower of the two effusive vents at the base of the NSEC cone produced a lava flow that traveled 1.
Around ash puffs rose from the crater, followed by incandescent tephra ejected at Within a few minutes sustained lava fountains were observed, along with a tall eruption plume that drifted E. On 20 April several lava flows on the W wall of the Valle del Bove interacted with the snow, generating explosions and lahars.
Around lava-fountain activity decreased and turned into explosions and ash emissions. At the paroxysm was over. In the evening, the lava flow emitted from the effusive vent at the base of the SE part of the NSEC cone was still well-fed. Poor weather conditions prevented visual observations until the evening of 21 April, when surveillance videos showed sporadic Strombolian explosions accompanied by small ash puffs at the NSEC, and the emission of a small lava flow from the base of the cone.
Sezione di Catania - Osservatorio Etneo reported that the tenth eruptive episode of began at Etna's New Southeast Crater NSEC on 8 April with sporadic ash emissions occasionally accompanied by incandescent material. A large explosion at was heard up to 15 km away. The ash emissions continued for about 48 hours. In the late afternoon on 10 April Strombolian activity began, producing minor ash emissions during some of the explosions.
In the morning on 11 April Strombolian explosions occurred about every seconds, ejecting incandescent pyroclastics several tens of meters above the crater rim. Strombolian activity increased slowly in intensity and frequency of explosions throughout the day; contemporaneously the volcanic tremor amplitude continued to show a gradual rise.
Late in the afternoon frequent and very powerful Strombolian explosions occurred every seconds and were widely audible around the volcano. Jets of incandescent pyroclastics often rose m above the crater rim and generally contained minor amounts of ash. Around , a small amount of lava flowed over the deep breach in the SE rim of the crater. In the late evening it stopped and showed evidence of cooling. Throughout the night powerful explosions alternated with intermittent, low lava fountains.
At daybreak on 12 April a dense eruption plume containing relatively minor amounts of pyroclastic material drifted ESE. At a flow of hot pyroclastic material from the same area traveled about 2 km NE in less than 1 minute. In the meantime, eruptive activity continued at the NSEC with frequent, powerful Strombolian explosions and emission of modest quantities of volcanic ash, which was rapidly dispersed. Shortly before , the eruptive activity changed from low lava fountains to Strombolian explosions and intermittent ash emissions.
Vigorous ash emissions resumed at both from the main vent of the NSEC and from the saddle vent. Expulsion of blocks, bombs and ash from the saddle vent continued until , when the main vent of the NSEC reactivated, and for the next nearly 20 minutes both vents were the source intense ash emissions.
The activity shifted back entirely to NSEC, entering into the true paroxysmal phase of this episode at with sustained lava fountaining, accompanied by a return to high levels of the volcanic tremor amplitude.
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