It rises 10, feet 3, m above the floor of the Tyrrhenian Sea. This photo shows the volcanic island of Stromboli. Photograph courtesy of and copyrighted by Mike Lyvers. Stromboli is one of the most active volcanoes on Earth. It has been in nearly continuous eruption for about 2, years some volcanologists suggest 5, years. Most of the present cone was well developed 15, years ago. This photo shows the volcano and town of Stromboli.
Photographs courtesy of and copyrighted by Mike Lyvers. Most eruptions at Stromboli consists of small gas explosions that hurl incandescent blobs of lava above the crater rim.
Several explosions occur each hour. Larger eruptions and lava flows are less frequent. When this type of eruption is observed at other volcanoes it is often referred to as a Strombolian eruption. No one was directly injured by the fallout, but a girl fell and broke her arm when panic caused a rush towards the village. According to numerous eyewitnesses, the explosions began without premonitory activity. Seismic records from the Ginostra station 1. However, a slight increase in volcanic tremor amplitude and energy of seismic shocks was observed a few days before the explosions by a portable seismograph operating on the N flank 1.
The rate of gas emission and frequency of explosions gradually returned to a normal level in the following days. Further Reference. Information Contacts: S. Falsaperla , G. Frazzetta , and E. Privitera , IIV; M. Rosi , Univ di Pisa. Geologists from Ruhr Univ. On 15 September between and , 10 eruptions occurred from at least 3 vents, ejecting glowing spatter to m above the crater terrace. No ash plumes were observed, and only two of the eruptions were audible from. Activity seemed comparatively weak and irregular during observations of the crater terrace from about on 16 September until the next day from Pizzo sopra la Fossa, m elevation.
Individual bursts were separated by quiet intervals of minutes. The SE walls of the active vents seemed to have grown unusually high. Next to the most active vent was a second [] on figure 2 which apparently contained a lava lake.
Although not visible, the lava lake's presence was suggested by a continuous glow and dull surf-like sounds. Geologists suggested that the two vents probably coalesced sometime after midnight on 17 September, as explosive activity from the first vent was much reduced and glow was also visible above it. Between and , two brown ash plumes rose from the center of Crater 1 to perhaps m above the vents, dropping some ash on the observation platform. A small ash plume was visible during the evening when the volcano was frequently observed from the E coast.
Crater 3 erupted only three times during the observation period, but often made loud crashing noises without visible ejections. No earthquakes were felt. Information Contacts: B. Behncke , Ruhr Univ, Germany. During 5 October fieldwork, Open Univ geologists noted that morphology of the active craters appeared similar to that of late Crater 1 see figure 2 was the most active, with two open vents at about the same positions as [] and [], both containing magma at or near the surface.
Bombs rose as much as m above the rim. Explosions from vent [] were less frequent and less powerful. Crater 3 was also active, with eruptions at an average of once every 45 minutes, ejecting glowing bombs obliquely to the W, into adjoining Crater 2. Oppenheimer , Open Univ. Stromboli was visited on 29 March and April. Poor weather on the 29th obscured the active summit vents until late afternoon, when six eruptive episodes were observed between and Five were accompanied by emission of dark gray to black ash plumes that rose m above the two active vents.
Observations from the summit between on 1 April and the next morning revealed morphologic changes that had occurred in the vent area since September Crater A [termed Crater 1 in previous reports; compare figure 2 and figure 3 below] included at least five vents, four of which were active. Each of the eruptions was accompanied by a few seconds of deep but not very loud rumbling. In the NE part of Crater A, a cluster of open vents several very small and three larger contained active magma and glowed intensely at night.
They emitted burning gases but no spatter. Crater B [coalesced from craters formerly termed 2, 3, and 4; compare figures 2 and 3 below] included at least 4 vents, and others were probably hidden from view by intense gas emission and topographic obstacles.
In its center was a symmetrical spatter cone m high with a glowing summit vent and a small steaming hornito near its SW base. The cone was covered with yellowish green sublimates and was not ejecting tephra. Vent 5, frequently active in September, erupted only once every hours. Its eruptions lasted up to 30 seconds, sometimes consisting of several pulses of lava fountains that reached m above the rim, accompanied by loud rumbling.
A few were accompanied by ejection of several glowing blocks, probably from the conduit walls. Vent 3, between craters A and B, remained inactive during the observation period. During the afternoon of 3 April, ash emission reportedly became stronger and could be seen from villages on the SE and E sides of the island.
An automatic telemetering short-period seismic station was installed near the active craters in October to monitor explosive activity and volcanic tremor. During the second half of November, several events with peculiar waveforms were recorded over a 4-day period.
Volcano guides who cooperate with volcanologists by noting visible activity, as reported below observed a new cone inside Crater 1 in December , and another cone that showed explosive activity between craters 1 and 2 in February In March, small cones produced bluish vapor inside Crater 3; emissions were accompanied by dull rumbling.
During the end of May and the first half of June 28 and 30 May, and 3, 4, 11, 13, and 15 June "normal" activity was observed at craters 1 and 3 with continuous explosions and ejection of incandescent material to m height.
Crater 2 was not active during this period. Morphologic changes to the new cones in Crater 1 were not evident. At least four large explosions occurred on 18 June between and Bartolo village on the NE side of the island. The wall between craters 2 and 3 collapsed. After this episode, explosive activity with ejection of small glowing blocks was observed at Crater 2 on 19, 21, 24, 25, and 28 June, and 2 July with almost continuous noisy gas emission on 25 June, and 4, 7, and 9 July.
An increase in the number of low-energy explosion earthquakes occurred July, while tremor amplitude decreased slightly. The number of events saturating the seismometer then increased sharply, while low-energy shocks dropped to near the long-term mean figure 6. Ash and lapilli emissions were continuous from the three craters, with increases in ejecta height and emission frequency after 19 July. The strong eruptive activity declined after 26 July. Crater 2 had been completely filled by tephra, but included two active vents characterized by synchronous noisy explosions.
Activity at Crater 3 was dominated by prolonged silent ash emissions. Continuous strong explosions from Crater 1 have been observed since 1 August. The number of explosions and seismometer-saturating events fluctuated during August, and were apparently inversely correlated figure 7. The highest peak in saturating events, 86, occurred on 13 August. Crater 2 resumed visible explosive activity with continuous rumbling August, while Crater 1 showed fumarolic activity August and explosive activity following the 13th.
Lapilli and cinders continued to fill the craters, completely covering the two cones in Crater 1 Riuscetti , Univ di Udine. At the end of August, explosive activity in Crater 1 became nearly continuous and tremor amplitude increased. The monthly average tremor amplitude was twice as high in September as in August. The daily number of events that saturated seismometers oscillated around a mean of 30 until 20 September before rapidly decreasing figure 9.
Saturating events and tremor amplitude reached a minimum during the first week in October, then remained at levels similar to those preceding the strong activity in the second half of July.
Volcano guides reported the following activity. Violent explosions with ash emission m high occurred from C3. Block ejection and gas emission took place from C2. Tephra was filling C3, where 4 new vents were forming on 15 September.
Geologists visited the summit area October. The activity was more vigorous than had been seen during 25 years of study at Stromboli. Strong explosions at minute intervals fed powerful brown ash emissions that reached about m height from vent 4 of C3. Nearly continuous bomb ejection from vent 1 of C1 was evident at night and gases were red. Stronger explosions were synchronous from many of the vents in the 3 craters.
Lava spilled out every few tenths of a second from one small cone 1 in C3. One vent 3 in C1 ejected gas nearly every second. Fumarolic activity was very intense, especially from the W rim of C3.
Although the eruption was apparently somewhat less vigorous in late October, activity observed by Boris Behncke on November was stronger than during his previous visits in September and March-April Vigorous gas emission fed a dense plume that obscured the vent area during the day, but visibility improved after sunset and a clear view of the craters was possible after on 7 November.
Although vent morphology had changed somewhat, vent configuration was much the same as in April. The main focus of activity was a cluster of at least four vents in C1 at the NE end of the summit crater group that were almost continuously erupting. Intense bomb and spatter ejection started at on 7 November and continued for at least 2 hours, with loud roaring like a jet aircraft.
The strongest eruptions occurred from C1's easternmost vent 1 , site of nearly continuous bomb ejections in early October. On 7 November, vent 1 ejected lava fountains to m height, often followed within seconds by eruptions from vent 3, the southernmost vent in C1.
Individual bursts of spatter, mostly from vent 3, were accompanied by loud explosions; gas had been emitted from this vent nearly once a second in early October.
Between stronger bursts, very small lava fountains were continuously active within vents 2 and 3. At on 8 November, fountains rose m from the latter vent, and loud roaring was continuing.
None of the vents produced ash plumes after on 7 November. The former vent at the NE end of C1 had apparently ceased erupting and may have been buried by the growing cone at vent 1, a prominent feature that had been too small to be visible from the summit in April.
Eruptive episodes from C3 at the SW end of the summit crater group occurred about twice an hour, producing lava fountains that rose as much as m, and sometimes diffuse brown ash plumes and light tephra falls onto the summit platform.
A strong eruptive episode at on 7 November was followed by bursts of spatter at intervals of seconds until Another particularly violent burst at covered most of the crater area with glowing bombs and spatter. Much of C3 had been filled with recent pyroclastics. Strombolian activity, abnormally vigorous during early October, began to decline in late October, and reached "normal" levels by the end of November.
On 23 November, weak fumarolic activity was observed on the W rim of Crater 3, and continuous rumbling punctuated by rare explosions were reported from vent 3 in Crater 1. No activity was observed in Crater 2. The average tremor amplitude and the number of major shocks decreased to levels lower than in June when the paroxysmal phase began figure 9.
Visits to the summit on 30 March and 9 April revealed that activity was restricted to Crater 1, and that the small cone 1 in Crater 3 had collapsed, forming a glowing red vent. Average tremor amplitude returned to normal following a low in December. The number of seismically recorded explosions increased briefly in late March and persistently from mid-April figure Volcano guides reported infrequent small explosive activity at the 3 craters during visits to the summit on 10, 15, and 16 April, and 1 May.
Table 1. Courtesy of M. Local residents reported a significant increase in the number of explosions on 19 May, after several weeks of weak activity. During a visit to the summit on the evening of 21 May, frequent strong explosions were observed at craters 1 and 3, with large ejections of incandescent material.
Thirty explosions were counted between on the 21st and the next day. Many ejecta fell onto the N flank's Sciara del Fuoco. Crater 2 and the small cones continuously emitted gas and vapor.
Riuscetti , Univ di Udine; M. Martini , Univ di Firenze; H. Average tremor amplitude declined slightly at the beginning of June while the number of saturating earthquakes rose sharply figure Volcano guides reported that the activity was concentrated at Crater 3, where explosions ejected glowing fragments and white gas columns that rose m in late June.
Explosions were rare from other craters, but tephra built small cones in Crater 2. White gas emission was continuous. The number and intensity of explosions has continued to fluctuate in recent months, with the average rate remaining slightly higher since mid-March.
The strongest ejected incandescent material toward the edge of the summit area. Most of the explosions were from Crater 1, the rest from Crater 3, with only gas emission evident from Crater 2 and from a small cone.
On this occasion and during other visits over the past several years, durations of precursory noises appeared linked to explosive vigor, with stronger explosions following noises lasting seconds, whereas second noises preceded weak explosions [see also ]. Information Contacts: H. De St. Cyr , Fontaines St. Martin, France. Explosive activity was restricted to crater C1 NE part of the summit area; figure 17 during 9 August fieldwork by F.
Glow from two small radial fissures in crater C2 was clearly visible at night. Sustained noisy gas emissions occurred about once an hour. Volcano guides had reported that activity was concentrated in crater C3 SW part of the summit area , but at its cone 1 only hot vapor emission was occurring, from two vents, on 9 August. Rare explosions, mostly ejecting tephra, took place at bocca 4.
Average tremor amplitude also remained relatively constant through the end of July, while large shocks nearly disappeared after a peak on 29 June figure Moderate activity was observed in early September, with explosive episodes about every 15 minutes at crater C3 and roughly hourly at C1.
Activity increased in the 3 hours of observations after on 6 September, with many moderate to strong explosions from the SW part of C3. Ejections of incandescent bombs and scoria sometimes lasted several minutes. Thick white vapor plumes rose from C2 and a small cone in its center, while blue SO 2 -rich plumes emerged from several other vents. Explosions from C1 were vigorous, ejecting glowing fragments and dark brown columns that rose m above the crater. C3's smaller explosive bursts, consisting of tephra-poor incandescent gas jets, were usually preceded by comparatively brief periods of increasing, noisy gas puffs; larger explosions that ejected a higher proportion of tephra followed longer intervals, with fewer or no precursory gas puffs.
Geologists attributed this pattern to intermittent closure by cooling of the lava-filled conduits to gas-bubble rise from the underlying magma body, allowing higher pressure to build at depth. Geologists concluded that combined with microprobe determination of the initial and residual sulfur content of Stromboli's lava, the SO 2 flux data require the degassing of 0.
Thus, gas output is essentially derived from magma stored within the volcano. To assess the amount of diffuse magmatic degassing through the volcanic pile, other than from the craters, infrared mass spectrometric profiling of CO 2 concentrations in the ground began on 11 September.
Concentrations gradually decreased toward the rim of this former crater, and no CO 2 anomaly was detected in outer areas to the S down to the Vancori rampart. Allard, P. Relatively low levels of activity lasted from mid-July to mid-August. The number of instrument-saturating events was low and concentrated on a few days during the second week in August, while average tremor amplitude remained relatively stable until it declined in late August figure The following report from Jonathan Dehn and Boris Behncke, on August activity, supplements information in Eruptions came from only two vents, one at the NE end of C1 figure 22 , and the other in the center of C3.
The former erupted frequently during the evening of 28 August producing fountains up to m high. Such eruptions lasted at least 10 seconds and began without any noticeable premonitory signs.
Bombs and spatter fell over much of the C1 area and into C2. These explosions were often preceded by an increasingly bright glow from the interior of C3. Two more vents 2 and 3 were visible within or near C1. Vent 2 appeared to be a larger pit created by collapse of the former vents 1 and 2.
This pit contained at least three active vents, of which two were open and displaying continuous glow and gas emission. Minor spattering from these vents occurred at times, often heralding eruptions from a third vent, in the center of the pit's floor, that was buried under a cover of bombs and scoriae.
Eruptions from this vent fragmented the old overlying material, forming diffuse ash plumes followed by the ejection of fresh glowing spatter. All of the ejecta from C3 fell back into the pit and onto its walls, and slumping of material from the pit's walls commonly covered the vent within seconds after each eruption. They contained small active lava ponds, or molten sulfur, and displayed pulsating gas emission. The ponds were located within a cavern, but no obvious vertical conduit was seen.
The rim of C3 was covered with a thin coating of fine tephra and fresh Pele's hair, but no ejecta fell in this area during the stay on the crater rim. From until about 29 August , the end of the summit visit, eruptions were separated by intervals ranging from 10 to 40 minutes.
Information Contacts: J. Dehn and B. The number of recorded explosion shocks increased irregularly through October figure 23 , a continuation of the generally increasing trend that followed the low activity of mid-July to mid-August. Tremor amplitude also increased figure The number of seismometer-saturating events was quite low and concentrated during the last week of October, when tremor was stronger and explosions were more frequent.
A team from the Univ di Udine climbed the volcano during the first week in October. Two vents were active in Crater 1, the first near the E rim, the second a m-high cone on its NW flank facing the Sciara del Fuoco. Explosions produced plumes m high, and ejected lapilli and sand-sized tephra.
Crater 2 was still marked by two radial fissures with clearly visible night glow, but its rim was no longer well-defined. Cone 1 in Crater 3 continued to produce white vapor from two vents. The westernmost vent of Crater 3 appeared to be the most active, and was at the center of a rapidly enlarging chasm.
It ejected clouds of black, sand-sized tephra to a maximum height of m. Along the ridge extending E from Pizzo sopra la Fossa the observation point SE of the active craters , a zone that once consisted of a few isolated hot spots had evolved to a thermal anomaly in September and a continuous line of fumaroles in October. Despite frequent heavy rains, no dark, ash-laden phreatomagmatic eruption plumes were observed.
When viewed from a ferryboat for about an hour during the morning of 18 March, the volcano erupted only once, shortly after , otherwise emitting only a gas plume. When operations resumed on 17 May, seismicity was unusually high, and the number of recorded events on 19 May was the largest since the station was installed in October figure Tremor amplitude briefly remained at November levels, but decreased rapidly beginning 20 May.
Daily summit observations May revealed that activity was concentrated in craters C1 vent 1 and C3 vent 4 with glowing tephra ejected to m height.
Noisy vapor emissions lasting seconds, accompanied by modest spatter ejection, occurred from a fissure in C2, on the W rim. Very modest activity continued from the small spatter cone in C3. During the night of May, Beat Gasser saw activity from several vents. Between explosions, a steady red glow and lava spattering were visible inside the crater, with spatter seldom reaching the crater's outer walls. Spattering declined before explosions.
Crater C2 produced noisy second gas emissions about once an hour. Ejections of a few red tephra fragments from C2 were seen during the night. East of C2, a steady red glow was visible at night within a small vent that was the source of pulsing gas emissions at 3-second intervals.
Eruptions occurred about twice an hour from C3, but like those from C1 were not evenly spaced. Two eruptions typically occurred roughly 10 minutes apart, followed by nearly an hour of quiet. The three active craters never erupted simultaneously, and their eruptions were separated by intervals of at least 5 minutes.
Riuscetti , Univ di Udine; B. Gasser , Kloten, Switzerland. Fieldwork during the first week in June revealed that eruptive activity was mainly concentrated in craters C1 vent 1 and C3 vent 4 , which fed black plumes no more than m high. A minimum of events was recorded on 24 June. After declining rapidly about 20 May, tremor energy returned to levels characteristic of the period since November Daily summit observations revealed frequent weak explosions and vigorous fumarolic activity in July and August.
Tremor amplitude was constant, and seismic activity was slightly above average. Tremor amplitude, measured with hourly second samples, generally averaged 0. Continuous spatter ejection; occasional vigorous explosions; seismicity increases. Fieldwork during the third week in October revealed that eruptive activity was mainly concentrated in crater 1, in the NE part of the summit area. Spatter ejection was nearly continuous and explosions were frequent from C1's NE vent.
Rare strong explosions from vent 5 of C3 SW summit area fed black plumes about m high. Strong noisy degassing occurred from C2, with some spatter emission from vents that had developed from pre-existing fissures. C1 had been partially filled with debris and the spatter cone in C3 destroyed.
Tremor energy and the number of earthquakes increased steadily in September and October figure A short series of violent explosions occurred from the summit craters on 10 February at GMT, ejecting a large tephra column. Only weak degassing from the summit craters was visible during the next two days. The last earthquake was followed by high-amplitude tremor that lasted for 8 minutes, then gradually declined. No other anomalous seismic activity was recorded during the succeeding hours, although spectral amplitude of tremor was remarkably low.
No seismicity associated with the explosive activity was detected by any other stations in the IIV network. Tilt data from a shallow borehole station on the lower N flank at Punta Labronzo did not show any deformation suggesting significant magma storage in the volcanic edifice. Geologists noted that the activity appears to be comparable to similar episodes in and , thought to be caused by shallow gas accumulation building pressure in a feeder pipe.
Falsaperla and L. Velardita , IIV. Seismicity between 1 November and 28 February was stable except for two episodes of heightened activity figure On 10 February, three strong explosions occurred followed by a sudden decrease of tremor to about one-sixth the energy and one-third the number of events. In the week preceding the 10 February explosions, a large number of strong shocks occurred, with a maximum of 76 on 7 February.
After a few days of low seismicity following the explosions, tremor amplitude and the number of events gradually increased, reaching an isolated maximum on 22 February. Steve Matthews and Abigail Church observed vigorous Strombolian activity on 22 April at two m-high hornitos in crater C1 figure Semi-liquid bombs up to 2 m across reached up to m above the vents.
Stronger activity from all three craters every minutes consisted of gas emissions lasting as long as 15 seconds that ejected spatter as high as m. These stronger events appeared to occur in pairs from craters C3 and C2. An explosion from C3's vent 4 was often followed a few minutes later by an explosion from vent 2 in C2. Within C1, these larger explosions were only produced from the NE hornito vent 1.
Many incandescent fumaroles were visible on the hornitos and the floors of all three craters. Small amounts of spatter were also ejected from the fumaroles during the strongest explosive episodes. At about , shortly after sunset, lava was observed flowing slowly from a breach or bocca in the SW hornito vent 2 in C1. When observations ended at , the lava flow had divided and was beginning to form a moat around the hornitos.
A high level of eruptive activity was reported by Steve O'Meara on May. A gray fountain was observed from the lower NE slopes around that rose several hundred meters above the NE-most vent. Several strong explosions later that evening sent incandescent boulders rolling down the steep slope of the Sciara del Fuoco figure There were at least 8 vents active for several hours during summit observations the night of May.
Eruptive activity increased dramatically after the nearly full moon rose, peaked when the moon culminated in the southern sky, and waned before moonset. Lunar perigee when the moon is closest to the Earth occurred that night around Vent 1 in crater C1 figure 29 was a large dome-shaped mound with a summit crater and shallow floor filled with incandescent bombs from other vent explosions. Approximately every 30 minutes a powerful explosive blast, which sounded like a large cannon firing, violently blew the debris from the vent to heights of m.
Increased crater glow preceded these eruptions and most others. C1's vent 2 is a small cone with a peanut-shaped throat adjacent to and W of vent 1. This vent was continuously active with jetting sounds, blue flames, and spatter ejection. Thin streams of lava were erupted about every 5 minutes, with larger m sprays of lava about every 15 minutes. Occasionally, vents would erupt together. Ejecta from vent 3 was directed slightly NE, while blasts from vents 1 and 2 were directed vertically.
These explosions only lasted for a few seconds. Another less-active vent in C1, S of and adjacent to vent 1, also appeared to erupt synchronously with vents to heights of tens of meters. Eruptions from vent 2 in C2 occurred every minutes and lasted seconds each. Eruptions began with a strong jetting sound, after which a thin spray of lava would shoot out, followed by more vigorous jetting and extensive lava production.
Lava fountains reached heights of up to m. Lava was visible in the vent for about a minute after each eruption, with the surface continually being fractured by escaping gases. The lava would then slowly sink into the vent until it was no longer visible, although glow remained.
Two small adjacent vents in crater C3 were each surrounded by wide, shallow cinder rims. Eruptions were more frequent at the W vent, where explosions sent material m high about every 10 minutes during the most active periods.
These eruptions occurred without warning and were accompanied by a loud roaring noise. The largest eruptions from this vent produced very broad, expansive plumes shaped like large evergreen trees, which reached 30 m above the summit of the volcano. Another vent farther S may also have erupted, but that area was obscured by fumes and steam. The frequency of eruptions from each vent changed with time, but not the sounds, making it possible to know which vents were erupting.
By the morning of 3 May, activity had declined to one large explosion and a couple of smaller ones approximately every 20 minutes. Activity increased again after moonrise on 4 May and remained strong into the early morning.
Orange glow reflected by the clouds was observed that night in San Vincenzo. The next day, powerful eruptions continued from crater C3 and vent 1 in C1, but with less frequency.
Vents 2 and 3 in C1 glowed but did not have any strong eruptions. Observations ended about on 5 May. Seven eruptions were seen from the ferry on 6 May. Marcello Riuscetti reports that Stromboli guides observed a new cone in crater C1 and renewed activity at the C3 spatter cone in mid-May. On 16 May a small lava emission occurred from the base of a cone in C3. During the night the flow traveled 30 m down the slope, reaching the feeding fissure of the eruption before stopping.
Strong tremor and frequent explosions accompanied the lava flow. Seismicity number and energy of shocks, tremor energy increased in March and April after the low of 11 February The level of seismicity was very high in April figure 30 , with nearly continuous explosions in the second and third weeks. The strong Strombolian activity that accompanied the 18 May eruptive phase had stopped by 28 May.
Observations on 20 May revealed the end of lava emissions, intense Strombolian activity from the active vents of Crater 1 E crater , and degassing from Crater 3 W crater. Two cones were built by Strombolian activity inside Crater 1. The smaller one, only a few meters high, is located near the E rim. The second, located in the W part of Crater 1, was about 10 m high.
Strombolian activity was continuous in the small E cone, with ejection of bombs to a few meters, but was discontinuous and stronger in the W cone. Frequent explosions sent incandescent juvenile scoriae to m above the crater rim; they fell up to tens of meters away from the rim. Significant ejections occurred at intervals of about minutes. The funnel-shaped bottom of Crater 3 was obstructed by material, resulting in strong bursts of gas at intervals of minutes that formed a column up to m high.
The column consisted of brown, non-juvenile dust and blocks that fell back into the crater. The intensity of Strombolian activity at Crater 1 was lower on 27 May than during the previous visit, with fewer explosions and a decreased volume of ejected material. However, gas explosions at Crater 3 were continuing with the same frequency and intensity. No sounds indicative of Strombolian activity were heard during about one hour of observation 28 May.
Only weak degassing was observed from the vents in Crater 1. The degassing was interrupted at intervals of minutes by noisy gas explosions that formed a plume up to m high composed of brown, non-juvenile dust and a few scoria blocks.
At Crater 3, activity was similar to previous visits, with gas explosions and brown dust emissions at intervals of minutes. Calvari , IIV. Eruptive activity and seismicity decline from high levels in May; two strong explosions in October. After the eruption of a small lava flow in mid-May accompanied by high seismicity, there was an abrupt decay of seismic activity back to "normal levels" in early June figure Stromboli guides reported very low activity at the craters, with rare ejection of black ash from crater C3 and spatter from C1 during May to August.
Two strong explosions felt at on 16 October destroyed the small spatter cone in C3 that was built during the October eruption. Large blocks and spatter up to 2 m in diameter were ejected as far as m from the crater, and reddish ash fell on the NW slope of the volcano along the Sciara del Fuoco.
One woman was injured by hot ashes while sleeping near the crater area, and some bushes caught fire along the slopes. Tremor had begun to increase around of the previous day and then fell below the detection limits of the instruments one hour after the explosions.
An eruptive episode in the early hours of 23 October produced some strong explosions at both Crater 1 and Crater 2, ejecting spatter and lithic clasts. Two people who spent the night near the summit were injured by incandescent material during the explosions. Crater 1 the easternmost of the summit craters ejected bombs that measured up to 2 m across. Stromboli volcano has been particularly active in recent weeks, and spectacular eruptions have been captured in numerous videos that show the incredible phenomenon.
In these images below, captured by Landsat 8 during both night and day, we can also see this phenomenon from a different perspective; from space.
Another aim of these images is to promote the opportunity to download Landsat data through the ESA portals , where images captured every day are made available in near real time to the users and the scientific community. Stromboli Volcano. Latest eruption August Stromboli Volcano Stromboli is a small island in the Tyrrhenian Sea, off the north coast of Sicily, containing one of the three active volcanoes in Italy. Latest eruption August Landsat comparison images Night and Day Stromboli volcano has been particularly active in recent weeks, and spectacular eruptions have been captured in numerous videos that show the incredible phenomenon.
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