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  • Last Known Eruption
  • 38.404°N
  • 14.962°E

  • 500 m
    1640 ft

  • 211050
  • Latitude
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The Global Volcanism Program has no activity reports for Vulcano.

The Global Volcanism Program has no Weekly Reports available for Vulcano.

Index of Monthly Reports

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

06/1985 (SEAN 10:06) Microearthquake swarm and slight uplift

02/1988 (SEAN 13:02) New fracture system

05/1988 (SEAN 13:05) Higher fumarole temperatures and changing gas chemistry

11/1988 (SEAN 13:11) Fumarole temperature profiles

01/1989 (SEAN 14:01) CO2 in soil increases

10/1989 (SEAN 14:10) Fumaroles deposit sulfur

03/1990 (BGVN 15:03) High-temperature fumaroles; gas chemistry; small seismic swarms

04/1990 (BGVN 15:04) Continued fumarolic activity

08/1990 (BGVN 15:08) High fumarole temperatures and geochemical changes; seismicity suggests complex fumarolic system

04/1991 (BGVN 16:04) Fumarole temperatures increase

03/1992 (BGVN 17:03) Vigorous fumarolic activity

10/1994 (BGVN 19:10) Fumarole observations and temperatures from Gran Cratere

04/1995 (BGVN 20:04) Fumaroles at Fossa Grande and Forgia Vecchia craters

06/1995 (BGVN 20:06) Fumarole observations and measurements

10/1995 (BGVN 20:10) Fumarolic activity notably diminished from previous years

04/1996 (BGVN 21:04) Decrease in fumarole temperatures

07/1997 (BGVN 22:07) Fumarolic emissions during April from Fossa Grande

11/1997 (BGVN 22:11) Trends in fumarolic gas composition during 1996-97

10/1999 (BGVN 24:10) H2S, SO2, HF, HCl, and other gases tending to increase during 1998-99

Contents of Monthly Reports

All information contained in these reports is preliminary and subject to change.

06/1985 (SEAN 10:06) Microearthquake swarm and slight uplift

"Daily earthquake frequency in the Vulcano area showed, from 24 April, a significant increase (figure 1). Seismic energy may also be considered unusual even though magnitudes have not exceeded 2.5. Epicenters lay predominantly in the Gran Cratere area or very close to it (figure 2); focal depths were generally <1 km. The timing of event and energy distribution reveals the swarm character of the seismicity. Waveforms lead us to hypothesize that both degassing and fracturing phenomena occurred. A leveling survey carried out in May showed a slight uplift (1 cm) of the epicentral area with respect to the S part of the island."

Figure 1. Daily frequency of local earthquakes recorded 1 January-30 May 1985 by the Vulcano Cratere seismic station on the N flank. Courtesy of IIV.
Figure 2. Epicenters of the seven highest energy earthquakes that occurred in the Vulcano area 24 April-30 May 1985. Courtesy of IIV.

Further References. Frazzetta, G., Gillot, P.Y., La Volpe, L., and Sheridan, M.F., 1984, Volcanic hazards at fossa of Vulcano: Data from the last 6000 years: BV, v. 47, p. 105-125.

Falsaperla, S., and Neri, G., 1986, Seismic monitoring of volcanoes: Vulcano (southern Italy): Periodico di Mineralogia, v. 55, p. 143-152.

Information Contacts: S. Falsaperla and G. Neri, IIV.

02/1988 (SEAN 13:02) New fracture system

"After the last explosive event, in 1888-90, activity has been mainly fumarolic emissions of varying intensity at the crater. A new fracture system, transverse to the main alignment along which the more recent activity had originated, opened during the last few months.

"No important seismic activity was detected at the same time, and the progressive spreading trend beginning in 1985 was not substantially modified. The rate of longitudinal opening (some meters/month), however, along with the well-defined magmatic character of the gaseous species emitted through these fractures, appear as a clear indication of an increasing pressure from beneath."

Information Contact: M. Martini, Univ di Firenze.

05/1988 (SEAN 13:05) Higher fumarole temperatures and changing gas chemistry

OV has regularly collected data on fumarole temperatures, gas chemistry, and radon emission at Vulcano. Since September 1987, the temperature of a fumarole (F5) on the crater rim has increased from 310 to 335°C. In December, a new vent near F5 had a temperature of 370°C. Measurements since then (through May 1988) do not show continued temperature increases, although values reached 415° near the bottom of the crater on 1 April. Chemical analyses of fumarolic fluids show clear variations in several gases with time. H2S, H2, H2O vapor, and the S/C ratio strongly increased (figure 3), while Cl and CO2 decreased significantly. Equilibrium temperatures calculated from the gas/water shift reaction (CO + H2O <-> CO2 + H2) do not show any variation with an average temperature of ~ 400°C. Measurements of water wells also show an increase in radon activity (figure 4).

Figure 3. Percentages of H2S, H2, and H2O; and S/C ratio in gases from fumarole F5 on Vulcano's crater rim, July 1987-April 1988.
Figure 4. Temperature (top), and radon tracks/cm2/day (bottom), at a well (Pozzo Bambara) near Vulcano, 8 June 1986-11 April 1988.

OV geologists believe that the variations could be explained by two main hypotheses: 1) An increase in permeability of the shallow system because of more fracturing (13:02); 2) An increase in heat migration from deeper to shallower reservoirs, buffered by water as indicated by the higher water vapor content of the collected gases.

On 21 April, a landslide occurred on the NE flank of the island. Visual estimates yield a total avalanche volume of <50,000 m3. OV geologists note that a very limited phreatic explosion cannot be excluded as a cause for the landslide.

Information Contacts: D. Tedesco, J.-P. Toutain, L. Bottiglieri, R. Pece, and G. Luongo, OV.

11/1988 (SEAN 13:11) Fumarole temperature profiles

Geologists visited Vulcano on 25 and 30 October and 1, 7, and 8 November to obtain spatial and temporal surface temperature distributions (figure 5). Fumaroles typically formed linear zones of acid steam discharge. Transects of a zone extending 40 m somewhat radially along the N rim of Gran Cratere were surveyed.

Figure 5. Apparent surface temperature profiles transverse to an elongated fumarolic zone on the N rim of Vulcano's Gran Cratere measured at 0930 (filled circles) and 1230 (open circles) on 8 November. Temperatures were recorded using a Minolta Cyclops 33 radiometer operating at [8-14 µm] wavelength. Each datum is the integrated temperature for the whole field of view of the radiometer, between 2.5 and 4.5 cm in diameter. The later survey shows warming of the downwind side of the zone by hot clouds of condensates blowing across the area. Courtesy of C. Oppenheimer and D. Rothery.

Gas temperatures (recorded by a thermocouple) were stable during the visits. The highest temperature measured was 396°C, although surface temperatures above 300°C were uncommon and highly localized (<0.01 m2) near vents. Because sublimates were unstable above about 150°C, there was a gray sublimate-free belt within 5-40 cm of the vents, flanked on either side first by white ammonium chloride, then yellow sulfur sublimates.

Further Reference. Oppenheimer, C., and Rothery, D., 1991, Infrared monitoring of volcanoes by satellite: J. of the Geological Society, London, v. 148, p. 563-569.

Information Contacts: C. Oppenheimer and D. Rothery, Open Univ.

01/1989 (SEAN 14:01) CO2 in soil increases

CO2 concentrations in soil near Vulcano's summit crater increased substantially between measurements in October 1987 and November 1988 (table 1), correlated with increased fumarolic activity. Changes in concentrations and flow rates of CO2 gas have been correlated to volcanic activity by Elskens, Tazieff, and Tonai (1969).

Table 1. CO2 soil concentrations near Vulcano's summit crater, in mole %. Equipment, sites, and the person making the measurements were all identical for both data sets.

    Location                         Mole % CO2 Measurements
                                  October 1987   November 1988

    Flat crater bottom                0.1           60-80
    N trail from bottom of rim      0.1-0.5         10-40
    W and N rims                      0.1            7-22
    S and E rims                      1.6            4-30

Reference. Elskens, I., Tazieff, H., and Tonai, F., 1969, investigations nouvelles sur les gaz volcaniques: BV, v. 32, no. 3, p. 523-575.

Information Contacts: R.X. Faivre Pierret, DPT/SPIN/LESI CEA CEN, Grenoble, France; F. Le Guern, CNRS, CFR, CEN, Saclay, France.

10/1989 (SEAN 14:10) Fumaroles deposit sulfur

Geologists from Ruhr Univ visited Vulcano on 20 September and observed it from nearby Lipari Island on 19 and 21 September. During the afternoon of 19 September, strong gas emission occurred from the N part of Fossa Grande Crater, site of Vulcano's last eruption in 1888-1890. Gases were generally driven W by strong winds, but a white plume occasionally rose 300 m above the crater. Strong fumarolic activity occurred from numerous vents and fissures during the 20 September visit. Most of the activity was concentrated in the crater's N sector, but some occurred from the outer N flank and the inner S crater rim. Activity was most intense from a fissure that cut the crater rim along a roughly N-S trend. Just inside the crater, the fissure was up to 0.5 m wide and 1 m deep, with sharp edges coated with sulfur sublimates. Gases escaped with a hissing noise at the most active points. The volume of visible steam seemed to decrease during the afternoon, probably because of a decrease in humidity. Steam emission was still somewhat reduced when viewed from Lipari Island the next day.

During field studies 27-28 September and 3-4 October, Open Univ geologists noted that fumaroles seemed little changed from their previous visit in October-November 1988 (13:11). The fumarole fissure, ~ 40 m long, that crossed the N rim of the crater, was substantially deeper in places, perhaps from the loss of rock particles ejected by the pressurized gas flow. Gas temperatures along the fissure were generally about 275°C, with the highest value, 407°, at a vent on the crater's NE rim. Solid sulfur was abundant near fumaroles, as loose masses of yellow crystals, thin-walled tubules and cups containing drops of acid solution, and sulfur stalactites a few centimeters long within recessed vents. Liquid sulfur was also present, commonly as yellow, orange, or red droplets and dribbles, although one vent had produced a molten sulfur flow ~2 m long, and another contained a pool of liquid sulfur ~ 10 cm in diameter, with a temperature of 115.2°C.

Information Contacts: B. Behncke, Ruhr Univ, Germany; C. Oppenheimer, Open Univ.

03/1990 (BGVN 15:03) High-temperature fumaroles; gas chemistry; small seismic swarms

Fumarolic activity at Vulcano remained at a very high level in 1989. The temperature of a fumarole (F5) on the crater rim (figure 6) has remained stable at 310 ± 5°C; more than 90 samples have been collected since July 1987. In contrast, a fumarole (FF) inside the crater showed very high temperatures, reaching a maximum of 550°C in August-September 1989, 100° hotter than in 1988. February 1990 temperatures were 515° and 312° at FF and F5 respectively.

Figure 6. Map of Vulcano, showing locations of F5 and FF fumaroles.

Major chemical species (H2O, CO2, H2S, and SO2) showed large variations in concentration (figure 7). 3He/4He ratios were very high for all crater fumaroles (~60% mantle-derived He), remaining stable during 1989 at ~ 7.5-8.0 x 10-6. The 13C/12C ratio followed a similar trend to that of CO2, with very wide oscillations from about d13C 0.00 to -2.20+. Geologists noted that the chemical and isotopic trends suggest mixing of different sources.

Figure 7. Variations in concentrations of H2O (top), CO2, (center) and SO2 and H2S (bottom) at Vulcano's fumarole F5, 1987-90. Courtesy of OV.

Seismic activity was monitored by a permanent network installed by IIV, and a digital mobile seismic network operated by OV since 1987. Seismicity was at a low level and characterized by low-energy earthquakes occurring in swarm sequences. On the basis of their wave shapes and spectral characteristics, the earthquakes were divided into "Volcano-tectonic" and "Volcanic" events (figure 8) using the classification of Latter (1981). Volcano-tectonic earthquakes outside the Fossa cone and around the island showed clear P and S phases, high frequency contents, and represented the most energetic events (M < 1.6). Volcanic-type events showed very regular wave trains that were sometimes sharply monochromatic, and were characterized by low dominant frequencies and an absence of clearly identifiable phases. Their energy reached 1011-1012 ergs and their magnitudes were negative. Particle motion analysis revealed the presence of Rayleigh and Rayleigh-like waves with a prograde rotation; the arrivals of these two phases followed one another during such earthquakes. Geologists interpreted these events, centered in the Fossa crater, as being related to fumarolic gas flow at shallow depth.

Figure 8. Seismograms showing events classified as "Volcano-tectonic" (top) and "Volcanic" (bottom) at Vulcano.

Reference. Latter, J.H., 1981, Volcanic earthquakes and their relationship to eruptions at Ruapehu and Ngauruhoe volcanoes: JVGR, v. 9, p. 293-310.

Information Contacts: D. Tedesco, S. Vulcano, and G. Luongo, OV.

04/1990 (BGVN 15:04) Continued fumarolic activity

A summit climb on 31 March revealed only minor changes since September 1989 (14:10). Gas emission continued from the fissure on the N rim, at high pressure from its 10-15-cm-wide central portion. Rocks up to 5 mm in diameter were re-ejected when thrown into the fissure's central section. The resulting gas plume rose 300-400 m during rainy weather on 3 April, but was considerably smaller at other times. Weak fumarolic activity was also occurring on the outer SE crater wall, and a new fumarole had formed on the NW flank.

Information Contact: B. Behncke, Ruhr Univ.

08/1990 (BGVN 15:08) High fumarole temperatures and geochemical changes; seismicity suggests complex fumarolic system

"OV geologists visited Vulcano island in recent months. Temperatures of the sampled crater fumaroles F5, F5AT, and FA (figure 9) were 300°, 420°, and 537°C respectively on 18 August. During two night inspections inside the crater, bright glow was discovered at all fumaroles up to 530°C and blue flames were discovered at some points in the fumarolic field, probably revealing burning of molten sulfur.

Figure 9. Map of Vulcano showing the locations of fumaroles (F5, F5AT, and FA), and the seismic stations (CNW and CNE) used during the May 1990 microseismicity study. Courtesy of the Osservatorio Vesuviano.

Geochemistry. "Several chemical variations have been observed since April 1990 in fluids sampled at F5 fumaroles. A sharp decrease in H2O content similar to that recorded in 1988 (see figure 7) has occurred. Consequently, CO2, SO2, N2, HCl, and HF increased in content. At the same time, the S/C ratio significantly decreased. Chemical variations seemed to follow the trend recorded in 1988. These data agree with an unpublished model by Tedesco et al. of possible mixing between shallow and deep fluids, continuously occurring in different proportions before gas escapes from fumarolic vents.

Geophysics. "A microseismicity study of Vulcano crater by the OV in the summer of 1988 revealed the presence of Rayleigh and Rayleigh-like waves with a prograde rotation (15:03). The analyzed earthquakes were low-frequency events, with energy up to 1012 ergs, showing phases not clearly identifiable on seismograms. Most scientists believe them to be related to gas flow in fumarolic conduits (Blot, 1971; Latter, 1971). Particle motion analysis revealed retrograde and prograde elliptical orbit phases that followed one another during such earthquakes (figures 10 and 11). This physical phenomenology was interpreted as due to propagation and reflection of tube waves in a fluid-filled conduit (White, 1983; Toksoz and Stewart, 1984; Hardage, 1985). According to such a model, the successive rotation inversions of particle motion would be generated from alternating downgoing and upgoing tube waves. The non-correlativity of phase arrivals among the seismic network stations suggested complex circulations discriminated by tube heights, because of the presence of several reflecting points (in fact seismographs operated at different altitudes on Vulcano island).

Figure 10. Particle motion on the vertical-radial plane (with respect to crater axes) derived from Vulcano seismogram in figure 11. Numbered frames correspond to seismogram segments and represent several seconds; arrows mark rotation inversions relating to phase arrivals. Courtesy of the OV.
Figure 11. Filtered three-component signal of the Vulcano microearthquake analyzed in figure 10. Dotted lines discriminate temporal intervals (numbered frames in figure 10) for particle motion, and arrows mark arriving of retrograde and prograde phases. Courtesy of OV.

"In May 1990, a survey was carried out to verify the possible presence of correlativity and synchrony of phase arrivals at two seismic stations placed at the same altitude on the top of the crater. Stations were installed at ~90° from each other with respect to the crater axes (figure 9). Notwithstanding the low activity level during the 2-week recording period, the few events analyzed show the same phenomenology observed on 1988 records. Unfortunately, the expected correlativity was absent. The negative result, not invalidating the proposed model, suggested a complex geometry of the tube-like source structure, such as non-vertical orientation."

References. Blot, C., 1971, Etude sismologique de Vulcano: Cahiers ORSTOM serie Géophysique, no. 11.

Hardage, B.A., 1985, Vertical seismic profiling, Part A: Principles, in Helbig, K., and Treitel, S., eds., Handbook of Geophysical Exploration: Geophysical Press, p. 71-95.

Latter, J.K., 1971, Near Surface seismicity of Vulcano, Aeolian Islands, Sicily: BV, v. 35, p. 117-126.

Toksoz, M.N., and Stewart, R.R., eds., 1984, Vertical seismic profiling, Part B: Advanced Concepts, in Helbig, K., and Treitel S., eds., Handbook of Geophysical Exploration: Geophysical Press, p. 256-313.

White, J.E., 1983, Underground sound: application of seismic waves: Elsevier, New York, p. 139-191.

Information Contacts: D. Tedesco, S. Vulcano, and G. Luongo, OV.

04/1991 (BGVN 16:04) Fumarole temperatures increase

Observations at "La Fossa" crater in recent years have included changes in fumarole temperatures and chemical compositions, ground deformation, and opening of new fractures. Data collected since a systematic surveillance program began in 1977 have allowed geologists to identify different stages during which changing contributions of magmatic gases and water caused fluctuating fumarole outputs. The interaction of heat rising from depth with shallow aquifers has produced changes in water vaporization and pressure as the heat/water ratio varied.

Only minor crater activity occurred until 1987, probably because of the constraints imposed by a limited fracture system on the thermal input. Since then, a sharp change has been observed, with ground inflation and significant increases in the maximum temperature and water concentration of emitted fluids.

In 1990, a further increase in the maximum temperature (to 620°C) and decrease in water contents of fumarole fluids were interpreted as a consequence of increased heat flow, causing significant aquifer depletion (15:08).

The most recent (April 1991) observations indicate that fumarole temperatures are again increasing, and significant vaporization as well as new inflation can be expected. Geologists noted that the long-lasting instability of La Fossa's NW sector could result in some form of collapse that could create problems for the local community.

Further References. Falsaperla, S., Frazzetta, G., Neri, G., Nunnari, G., Velardita, R., and Villari, L., 1989, Volcano monitoring in the Aeolian Islands (southern Tyrrhenian Sea): the Lipari-Vulcano eruptive complex, in Latter, J.H., ed., Volcanic Hazards: Assessment and Monitoring: Springer-Verlag, p. 339-356.

Martini, M., 1989, The forecasting significance of chemical indicators in areas of quiescent volcanism: examples from Vulcano and Phlegrean Fields (Italy), in Latter, J.H., ed., Volcanic Hazards: Assessment and Monitoring: Springer-Verlag, p. 372-383.

Martini, M., Giannini, L., Buccianti, A., Prati, F., Legittimo, P.C., Iozelli, P., and Capaccioni, B., 1991, 1980-1990: Ten years of geochemical investigation at Phlegrean Fields (Italy): Journal of Volcanology and Geothermal Research, v. 48, p. 161-171.

Martini, M., Giannini, L., and Capaccioni, B., 1991, Geochemical and seismic precursors of volcanic activity: Acta Vulcanologia, v. 1, p. 7-11.

Martini, M., Giannini, L., and Capaccioni, B., 1991, The influence of water on chemical changes of fumarolic gases: different characters and their implications in forecasting volcanic activity: Acta Vulcanologia, v. 1, p. 13-16.

Information Contact: M. Martini, Univ di Firenze.

03/1992 (BGVN 17:03) Vigorous fumarolic activity

Vigorous fumarolic activity was continuing from the N rim of the historically active crater (Fossa Grande) and from thermal areas on the upper N flank during a visit on the afternoon of 18 March. Most of the fumaroles were concentrated along the N crater rim, inside the N part of the crater, and on the N flank of the wall of tephra built during Vulcano's last eruption, in 1888-90. The main fumarole field appears to have extended a short distance to the E along the N crater rim, where new vents had formed since Behncke's last visit in November 1990. A new linear zone of high-pressure gas emission has developed roughly parallel to the large fissure that formed after 1988 on the N crater wall. Fumarolic activity from scattered vents on the upper N flank seemed to have increased since November 1990, and a less-prominent thermal area on the outer SE flank included at least 7 weak fumarolic vents.

Intense hydrothermal alteration and erosional undercutting have occurred on the upper N flank, around the S rim of the 18th-century Forgia Vecchia craters. Extension cracks have appeared within a few meters of the steep N slope, and deep gullies extend toward the coastal town of Porto di Levante.

Information Contact: B. Behncke, GEOMAR, Kiel.

10/1994 (BGVN 19:10) Fumarole observations and temperatures from Gran Cratere

"Gran Cratere was visited on 7 and 11 October 1994 by Open Univ geologists and observations were made of the fumarole zone, which extends from the floor of the lower crater to the rim of the upper crater, and onto the NE outer crater flanks. On 7 October, temperatures of >500 fumaroles were measured (table 2) with a Minolta/Land Cyclops Compac 3 hand-held radiometer (8-14 mm). The only area within the fumarole zone not sampled was that extending from the rim of the lower crater to its floor. Because radiant temperatures have not been corrected for spectral emissivity, all are given as brightness temperatures.

Table 2. Summary of fumarole and fissure temperatures measured at Gran Cratere, Vulcano, 7 October 1994. The upper temperature range of the Compac 3 is given as 500°C by the manufacturer. Courtesy of A. Harris, Open Univ.

    Area                     Temp (°C) on     Mean   Number of
                             7 Oct 1994       Temp   fumaroles
    Upper crater NE rim:
    S half                     88.7-305       161      105
    N half                     93.3-449       188       45

    Fissures cutting the
    N end of upper crater       134-345       257       64
    rim fumarole zone

    Upper crater inner flank:
    Upper slopes, S half        107-315       184       56
    Upper slopes, N half       92.7-334       169       98
    Lower slopes, S third       112-362       213       36
    Lower slopes, middle third  115-506*      363       39
    Lower slopes, N third       117-485       297       39

    Bench between foot of
    the upper crater and
    the lower crater rim        113-371       222       22

"Fumaroles along the crater rim are located in a sinuous 1-3 m wide fissure that runs along the NE crater rim for ~200 m. Within this zone, low-temperature (54-148°C) and medium-temperature (164-286°C) fumaroles dominate and sublimates are common. Maximum temperatures (305-449°C) came from fumaroles within gray rubble-filled depressions, which occurred less commonly along this fissure line. The crater rim fumaroles were bounded at the N end by a rubble-filled fissure, ~60 m long, which cuts the rim obliquely with a N-S trend and extends onto the outer and inner slopes of the crater. This fissure contains fumaroles at temperatures between 134 and 345°C (table 2). The upper slopes of the inner NE flank of the upper crater and S edge of the fumarole zone were dominated by low- to medium-temperature fumaroles, with less common high-temperature fumaroles in rubble-filled depressions and fissures. However, the lower slopes of the inner NE flank of the upper crater were dominated by an area (~70 x 15 m) of gray rubble and high-temperature fumaroles (211-507°C), with lower temperature fumaroles (60-191°C) and sublimates far less common. High temperatures were found in the middle and towards the N side of this area. During measurements there was constant discharge of gases from the fumaroles."

Information Contacts: A. Harris, Open Univ.

04/1995 (BGVN 20:04) Fumaroles at Fossa Grande and Forgia Vecchia craters

During an 18 Apri visit by Boris Behncke to the Fossa Grande crater the most vigorous fumaroles were present on the N inner crater rim and near its bottom. The main focus of fumarolic activity had shifted notably from the crater rim towards its center since his March 1992 visit (BGVN 17:03). Some of the spectacular fissures on the outer N crater wall were inactive, but several large fumaroles had formed near the crater floor. Molten sulfur was present in many fumaroles on the crater rim. Fumarolic activity on the oversteepened S part of the 18th century Forgia Vecchia craters and on the upper SE slope of the cone has changed little since 1992. Fumaroles were also active at Gran Cratere in October 1994.

Information Contacts: Giada Giuntoli and Boris Behncke, GEOMAR Research Center, Dept. of Volcanology and Petrology, Christian-Albrechts-Universitat zu Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany (Email:

06/1995 (BGVN 20:06) Fumarole observations and measurements

SVE members who visited Gran Cratere on the Fossa Cone on 21 May observed the fumarole zone that extends from the floor of the lower crater to the rim of the upper crater and onto the NE flanks of the outer crater. Fumarolic activity has remained steady for several months with maximum temperatures of 500-600°C. Although the E-W fissure inside the crater (near the fumarole area) still appeared to be moving, scientists at Palermo University reported no increased seismicity or inflation.

Periodic fumarole surveys made by Marino Martini within the "La Fossa" crater between April 1993 and April 1995 showed a significant decrease in temperatures. Fumarole emissions during this period exhibited increased H2O and CO2 gas with a corresponding decrease in volcanic gases (table 3). Marino suggested that the changes were caused by increased permeability, allowing additional shallow groundwater to dilute the fluids eventually emitted at the surface. Increased vapor pressure could affect the precarious stability of the NW slopes of the crater, a serious potential hazard.

Table 3. Fumarole temperatures and gas compositions at Vulcano, April 1993 and April 1995. Courtesy of Marino Martini.

    Component        1993     1995

    Temp (deg. C)     635      476

    H2O vol. %      88.80    90.93
    CO2 % dry gas   88.96    96.25
    H2S              1.72     0.82
    SO2              3.97     0.90
    HCl              1.89     0.82
    HF               0.29     0.12
    B                0.035    0.040
    H2               1.30     0.21
    N2               1.35     0.64
    CO               0.078    0.027

Information Contact: Henry Gaudru, Societe Volcanologique Europeenne (SVE), C.P. 1 - 1211 Geneva 17, Switzerland; Marino Martini, Department of Earth Sciences, University of Florence, Via G. La Pira 4, 50121 Florence, Italy.

10/1995 (BGVN 20:10) Fumarolic activity notably diminished from previous years

Fumarolic activity, vigorous in the late 1980s and through 1994, notably diminished in 1995 (BGVN 20:04 and 20:06). During observations in September, the steam and gas output of the most conspicuous fumaroles, at the N rim of the Fossa Grande crater, was back to pre-1985 levels, and no longer formed sizeable gas plumes. Some of the formerly most vigorous fumaroles and steaming cracks were no longer active. Strong gas emission still occurred from fumaroles in the oversteepened and unstable Forgia Vecchia area, below the N rim of the Fossa Grande, and hydrothermal alteration continued to weaken the rock. Several blocks of strongly altered rock with volumes of ~100-500 m3 each had already detached and subsided by 10-20 cm, and may fall. However, it was uncertain whether they would reach the S margin of the village below the Fossa cone. Fumarolic activity also continued from numerous places on the beach N of the "Faraglione" and on the low isthmus connecting Vulcanello to the main body of Vulcano island. During a visit to the western-most (and most recent) crater of Vulcanello on 13 September, no evidence of recent fumarolic activity was found in its NE part where intense fumarolic activity took place until the mid-19th century.

Information Contacts: Boris Behncke and Giada Giuntoli, Department of Volcanology and Petrology, GEOMAR, Wischhofstr. 1-3, 24148 Kiel, Germany (Email:, URL:

04/1996 (BGVN 21:04) Decrease in fumarole temperatures

The "La Fossa" crater was visited during 9-11 May by a group from the Federal Institute of Technology in Zurich. Fumarolic emissions were observed on the SW inner crater wall, on the outer N slope ~100 m below the crater rim, and on the NE outside flank about half way down from the rim towards the sea. During the night of 9-10 May, several new fissures, 2-3 m long and 2-5 cm wide, opened on the inner crater slopes. They formed as an extension of a major fissure reaching W from fumarole FF, concentric to the crater rim. Temperatures of gases emitted from these fissures ranged from 160 to 220°C. During the same night, pre-existing fissures widened by a few centimeters (<5 cm). New fissures just below the rim towards the crater were a few millimeters in width. The inner crater slope showed widening of both radial and tangential fractures.

Fumarole temperatures were measured on the NE crater rim and on the inner crater flanks, but those from radial fractures in the inner crater were not measured. Maximum temperature observed was 507°C on an extension fissure of fumarole FF on the inner crater slopes (table 4). This compares to the maximum temperature of 552°C in the same period last year at the same location. Temperatures on the crater rim peaked at 326°C at fumarole F5 compared to 512°C last year. Temperatures of outlets situated at the edge of the slope from the inner crater to its floor reach a maximum of 435°C. Fumarole temperatures therefore showed decreasing trends, but maximum temperatures remained high. The decrease was strongest at the rim fumaroles.

Table 4. Measured temperatures at La Fossa Crater, Vulcano, in May 1995 and 1996. Fumaroles F0/F1 and F5 are located at the crater rim; FF, FA and the extension fissure occur in the inner crater. Courtesy of C. Wahrenberger.

                    Peak Temperature (°C)
    Fumarole     1-5 May 1995  9-11 May 1996

       F0            369            320
       F1            302            320
       F5            512            326
       FF            484            435
       FA            474            445
     Extension       552            507
     fissure FF

Temperature measurements were done using a Cr-Al Type K thermocouple at ~5 cm below the surface. All 1996 measurements were taken at the same locations as those made in 1995. Temperatures at each point were also taken on three successive days; deviations in 1996 were <5°C from day to day. Gas and condensate samples were also taken because the research focus of the group is trace-element transport in volcanic gases.

Information Contacts: Christoph Wahrenberger, Terry M. Seward, and Volker Dietrich, Institute for Mineralogy and Petrography, Federal Institute of Technology, Sonneggstrasse 5, 8092 Zurich, Switzerland (Email:

07/1997 (BGVN 22:07) Fumarolic emissions during April from Fossa Grande

Fumarolic emissions observed by Boris Behncke during 24-30 April from the Fossa Grande crater appeared more voluminous and denser than during 1995-96. The main focus of the fumarolic activity was in the N-central part of the crater, but fumaroles also appeared more vigorous on the N crater rim.

Information Contact: Boris Behncke, Istituto di Geologia e Geofisica, Palazzo delle Scienze, Corso Italia 55, 95129 Catania, Italy (Email:, URL:

11/1997 (BGVN 22:11) Trends in fumarolic gas composition during 1996-97

Periodic observations of the chemical composition of fumarolic gases have been made at Vulcano since 1977. Several fumaroles with different temperatures but similar chemical compositions were observed. Differing trends in fumarolic gas composition at different locations on Vulcano have been observed during 1996-97.

Table 5 shows the trend in chemical composition of gases emitted by fumaroles on the rim and inside the crater during 1996-97. For fumaroles on the rim, percentages of typical magmatic species such as SO2, H2, and CO increased during 1996-97; percentages decreased for fumaroles inside the crater. Scientists estimated that the magmatic system was opening on the rim and closing inside the crater. This evolution pattern revealed that the stability of the system was affected by deformation of the Fossa cone produced by increased vapor pressures at depth.

Table 5. Fumarolic gas composition (percentages) on the rim (A) and inside the crater (B) of Vulcano, 1996-97. Courtesy of M. Martini.

                    A (rim)          B (crater)
                 1996     1997      1996    1997

    Temp. (°C)    348      328       399     426
    H2O (vol.)   84.41    88.86     81.50   85.38
    CO2 (dry)    93.90    92.37     97.40   97.13
    H2S           2.66     3.10      0.41    0.40
    SO2           1.46     2.11      1.11    0.99
    HCl           0.97     1.26      0.54    0.78
    HF            0.52     0.46      0.077   0.029
    B             0.017    0.023     0.014   0.017
    NH4           0.010    0.010     0.006   0.017
    H2            0.041    0.121     0.081   0.048
    N2            0.525    0.547     0.580   0.513
    CO            0.00047  0.00072   0.0038  0.0024

Correction: Boris Behncke (Istituto di Geologia e Geofisica at Università di Catania) noted that during a visit in late April 1997 (BGVN 22:07) steam emissions from the Fossa Grande crater appeared slightly more voluminous than during visits in 1995 and 1996. This statement may have created a false impression of renewed increase in fumarolic activity when it was actually due to the relative humidity of the air. Fieldwork by other scientists during spring 1997 revealed low fumarole temperatures and less abundant emissions. This was confirmed by Behncke during June-July and 10-12 October when fumarolic emissions were the lowest since 1989.

Information Contact: Marino Martini, Dipartimento di Scienze della Terra, Università di Firenze, Via La Pira 4, 50125, Firenze, Italy (Email:; Boris Behncke, Istituto di Geologia e Geofisica, Universitá di Catania, Corso Italia 55, 95129 Catania, Italy (Email:

10/1999 (BGVN 24:10) H2S, SO2, HF, HCl, and other gases tending to increase during 1998-99

Periodic inspections of Vulcano have indicated that the total output from the fumarolic field at the crater "La Fossa" started to decrease in 1995. However, an analysis of the chemical compositions of the gaseous phases conducted as a part of an overall evaluation of the volcanic system provides important volcanological details. Different trends observed between the fumaroles located on the rim and those inside the crater (see BGVN 22:11) indicate that the Fossa cone is affected by deformation, possibly the result of increased vapor pressure at depth. The chemical data from samples collected at the same locations during 1998 and 1999 (table 6) indicate similar trends of increasing magmatic gases. This could imply widespread opening of the system, which could affect the stability of the edifice.

Table 6. Chemical data measured at Vulcano, 1998-99. Courtesy of Marino Martini.

                     Crater Rim
                1997     1998    1999

    Temp. (°C)   328      320     303
    H2O (vol)   88.86    90.77   93.66
    CO2 (dry)   92.37    90.57   86.91
    H2S          3.10     3.41     6.54
    SO2          2.11     2.30     2.78
    HCl          1.26     1.47     1.77
    HF           0.46     0.42     0.66
    H2           0.12     0.18     0.22
    CO           0.0005   0.0006   0.0002

                    Inside Crater
                1997     1998     1999

    Temp. (°C)   426      281      379
    H2O (vol)   85.38    86.69    91.65
    CO2 (dry)   97.13    96.54    91.95
    H2S          0.40     0.26     1.25
    SO2          0.99     1.55     3.90
    HCl          0.78     0.43     0.85
    HF           0.03     0.08     0.13
    H2           0.05     0.18     0.08
    CO           0.0024   0.0114   0.0100

In addition to the data reported in table 6, temperature measurements taken along the N rim of Fossa crater some time during the period 2-16 July 1999 were reported by Claude Grandpey. The temperature in July was 340°C compared to ~410°C the previous April. Grandpey also reported stable temperatures (i.e., 95-100°C) at the fumaroles on the isthmus between Vulcano and Vulcanello.

Vulcano is located at the southern boundary of the Aeolian Islands, about 25 km from northern Sicily. It last erupted in 1888-90 when numerous meter-sized bombs and blocks fell in the area now occupied by the village of Vulcano Porto, which hosts thousands of tourists daily during the summer season. Vulcanello, the youngest part of Vulcano Island, began to form only ~2,100 years ago as an isolated island that later became connected with the main island. The latest activity at Vulcanello occurred in the 16th century when lava flows, now covered by large hotel complexes, were extruded.

Information Contacts: Marino Martini, Dipartimento di Scienze della Terra, Università di Firenze, Via La Pira 4, 50125, Firenze, Italy (Email:; Claude Grandpey, L'Association Volcanologique Europénne (LAVE), 7 rue de la Guadelopue, 75018 Paris, France (Email:

The word volcano is derived from Vulcano stratovolcano in Italy's Aeolian Islands. Vulcano was constructed during six stages during the past 136,000 years. Two overlapping calderas, the 2.5-km-wide Caldera del Piano on the SE and the 4-km-wide Caldera della Fossa on the NW, were formed at about 100,000 and 24,000-15,000 years ago, respectively, and volcanism has migrated to the north over time. La Fossa cone, active throughout the Holocene and the location of most of the historical eruptions, occupies the 3-km-wide Caldera della Fossa at the NW end of the elongated 3 x 7 km island. The Vulcanello lava platform forms a low, roughly circular peninsula on the northern tip of Vulcano that was formed as an island beginning in 183 BCE and was connected to Vulcano in about 1550 CE. Vulcanello is capped by three pyroclastic cones and was active intermittently until the 16th century. The latest eruption from Vulcano consisted of explosive activity from the Fossa cone from 1898 to 1900.

Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1968 Jul 11 ] [ Unknown ] Discredited    
[ 1892 Dec 14 ] [ Unknown ] Uncertain 0   5 km east of Vulcanello
1888 Aug 2 1890 Mar 22 Confirmed 3 Historical Observations Fossa
1886 Jan 5 ± 4 days Unknown Confirmed 3 Historical Observations Fossa
1873 Sep 1879 Confirmed 3 Historical Observations Fossa
[ 1831 ] [ Unknown ] Uncertain 1   Fossa
[ 1822 ] [ 1823 ] Uncertain 2   Fossa
[ 1812 ] [ Unknown ] Uncertain 1   Fossa
[ 1786 ] [ Unknown ] Uncertain 3   Fossa
1780 Unknown Confirmed 2 Historical Observations Fossa
[ 1775 ] [ Unknown ] Uncertain     Fossa
1771 Feb 17 1771 May Confirmed 3 Historical Observations Fossa
1731 1739 Confirmed 3 Historical Observations Fossa
1727 Unknown Confirmed 3 Historical Observations Forgia Vecchia II and Fossa
1688 Unknown Confirmed   Historical Observations Fossa
1651 Unknown Confirmed   Historical Observations Fossa
1631 Unknown Confirmed   Historical Observations
1626 Mar 1626 Apr Confirmed 3 Historical Observations
1618 Unknown Confirmed   Historical Observations
1550 Unknown Confirmed 3 Historical Observations Vulcanello III
1444 Feb 4 Unknown Confirmed 3 Historical Observations
1230 ± 20 years Unknown Confirmed 0 Magnetism Fossa, Palizzi lava flow
1200 ± 75 years Unknown Confirmed 2 Magnetism Vulcanello
1040 ± 75 years Unknown Confirmed 2 Magnetism
0925 ± 25 years Unknown Confirmed 3 Historical Observations
0729 Unknown Confirmed   Historical Observations Fossa
0526 (?) Unknown Confirmed 3 Historical Observations Fossa and Vulcanello III?
0144 Unknown Confirmed   Historical Observations Fossa
0050 ± 50 years Unknown Confirmed   Historical Observations Fossa
[ 0010 BCE ± 10 years ] [ Unknown ] Uncertain     Vulcanello
0024 BCE ± 5 years Unknown Confirmed   Historical Observations Vulcanello ?
[ 0043 BCE ] [ Unknown ] Discredited    
0091 BCE Unknown Confirmed 3 Historical Observations Vulcanello
0126 Jun BCE Unknown Confirmed   Historical Observations Vulcanello
0150 BCE ± 300 years Unknown Confirmed   Uranium-series
0183 BCE Unknown Confirmed 4 Historical Observations Vulcanello
0215 BCE Unknown Confirmed   Historical Observations Offshore vent
0300 BCE Unknown Confirmed 2 Historical Observations Fossa
0360 BCE ± 10 years Unknown Confirmed 2 Historical Observations Fossa
0475 BCE (?) Unknown Confirmed   Historical Observations Fossa
0950 BCE ± 500 years Unknown Confirmed 0 Uranium-series Fossa
1300 BCE (?) Unknown Confirmed 3 Tephrochronology Fossa
2650 BCE ± 1700 years Unknown Confirmed 3 Potassium-Argon Fossa
3550 BCE ± 1300 years Unknown Confirmed 0 Potassium-Argon Fossa, Punte Nere lava flow
6350 BCE ± 1600 years Unknown Confirmed   Potassium-Argon Monte Saraceno tephra
6550 BCE (?) Unknown Confirmed   Potassium-Argon NW side (Lentia)

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Feature Name Feature Type Elevation Latitude Longitude
Faraglione Cone
Fossa, La Tuff cone 391 m
Rosso, Monte Cone 328 m
Saraceno, Monte Cone 481 m
Sommata, La Cone
Vulcanello Cone 123 m

Feature Name Feature Type Elevation Latitude Longitude
Forgia Vecchia Crater 194 m
Fossa, Caldera della Caldera 481 m
Gran Cratere Crater 391 m
Piano, Caldera del Caldera

Feature Name Feature Type Elevation Latitude Longitude
Lentia Dome 187 m

Feature Name Feature Type Elevation Latitude Longitude
Acque Calde Thermal -6 m
Baia di Levante Thermal
Fossa Grande Thermal 290 m
Gelso Thermal -2 m
Istmo Thermal
La Roja Thermal
Punta Conigliara Thermal -15 m
The island of Vulcano in Italy's Aeolian Islands is the origin of the word volcano. It is seen here from the volcano observatory on the island of Lipari to the north, with the volcanic peninsula of Vulcanello, initially formed in 183 BC, in the foreground and Fossa cone in the background. Vulcano consists of at least three volcanic complexes, each of which is truncated by a small caldera. Volcanism has migrated to the north, with Fossa cone being the dominant Holocene center. The latest eruption took place from 1888 to 1890.

Photo by Richard Waitt, 1985 (U.S. Geological Survey).

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.

Arrighi S, Tanguy J-C, Rosi M, 2006. Eruptions of the last 2200 years at Vulcano and Vulcanello (Aeolian Islands, Italy) dated by high-accuracy archeomagnetism. Phys Earth Planet Int, 159: 225-233.

Blanco-Montenegro I, De Ritis R, Chiappini M, 2007. Imaging and modelling the subsurface structure of volcanic calderas with high-resolution aeromagnetic data at Vulcano (Aeolian Islands, Italy). Bull Volc, 69: 643-659.

Chiodini G, Cioni R, Guidi M, Marini L, 1991. Geochemical variations at Fossa Grande crater fumaroles (Vulcano Island, Italy) in summer 1988. Acta Vulc, 1: 179-192.

Clocchiatti R, Del Moro A, Gioncada A, Joron J L, Mosbah M, Pinarelli L, Sbrana A, 1994. Assessment of a shallow magmatic system: the 1888-90 eruption, Vulcano Island, Italy. Bull Volc, 56: 466-486.

De Astis G, Dellino P, De Rosa R, La Volpe L, 1997. Eruptive and emplacement mechanisms of widespread fine-grained pyroclatic deposits on Vulcano Island (Italy). Bull Volc, 59: 87-102.

De Astis G, La Volpe L, 1997. Volcanological and petrological evolution of Vulcano island (Aeolian Arc, southern Tyrrhenian Sea). J Geophys Res, 102: 8021-8050.

De Rosa R, Guillou H, Mazzuoli R, Ventura G, 2003. New unspiked K-Ar ages of volcanic rocks of the central and western sector of the Aeolian Islands: reconstruction of the volcanic stages. J Volc Geotherm Res, 120: 161-178.

Favalli M, Karatson D, Mazzuoli R, Pareschi M T, Ventura G, 2005. Volcanic geomorphology and tectonics of the Aeolian archipelago (Southern Italy) based on integrated DEM data. Bull Volc, 68: 157-170.

Frazzetta G, Gillot P Y, La Volpe L, Sheridan M F, 1984. Volcanic hazards at Fossa of Vulcano: data from the last 6000 years. Bull Volc, 47: 105-125.

Frazzetta G, La Volpe L, 1991. Volcanic history and maximum expected eruption at "La Fossa de Vulcano" (Aeolian Islands, Italy). Acta Vulc, 1: 107-113.

Frazzetta G, La Volpe L, Sheridan M F, 1983. Evolution of the Fossa cone, Vulcano. J Volc Geotherm Res, 17: 329-360.

Gamberi F, 2001. Volcanic facies associations in a modern volcaniclastic apron (Lipari and Vulcano offshore, Aeolian Island Arc). Bull Volc, 63: 264-273.

Gehring I, 2004. The use of grain-size dependent magnetic susceptibility and gamma-ray measurements for the detailed reconstruction of volcanostratigraphy: the case of La Fossa di Vulcano, S. Italy. J Volc Geotherm Res, 138: 163-183.

Gioncada A, Mazzuoli R, Bisson M, Pareschi M T, 2003. Petrology of volcanic products younger than 42 ka on the Lipari-Vulcano complex (Aeolian Islands, Italy): an example of volcanism controlled by tectonics. J Volc Geotherm Res, 122: 191-220.

Green J, Short N M, 1971. Volcanic Landforms and Surface Features: a Photographic Atlas and Glossary. New York: Springer-Verlag, 519 p.

Imbo G, 1965. Italy. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 18: 1-72.

Italiano F, Nuccio P M, 1991. Preliminary investigations on the underwater gaseous manifestations of Vulcano and Lipari. Acta Vulc, 1: 243-248.

Keller J, 1980. The island of Vulcano. Soc Italiana Min Petr, 36: 368-413.

Montalto A, 1996. Signs of potential renewal of eruptive activity at La Fossa (Vulcano, Aeolian Islands). Bull Volc, 57: 483-492.

Ventura G, 1994. Tectonics, structural evolution and caldera formation on Vulcano Island (Aeolian Archipelago, southern Tyrrheanian Sea). J Volc Geotherm Res, 60: 207-224.

Voltaggio M, Branca M, Tuccimei P, Tecce F, 1995. Leaching procedure used in dating young potassic volcanic rocks by the 226Ra/230Th method. Earth Planet Sci Lett, 136: 123-131.

Zanella E, De Astis G, Lanza R, 2001. Palaeomagnetism of welded, pyroclastic-fall scoriae at Vulcano, Aeolian Archipelago. J Volc Geotherm Res, 107: 71-86.

Volcano Types

Pyroclastic cone(s)

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Rock Types

Trachybasalt / Tephrite Basanite
Trachyandesite / Basaltic trachy-andesite
Trachyte / Trachyandesite
Basalt / Picro-Basalt


Within 5 km
Within 10 km
Within 30 km
Within 100 km

Affiliated Databases

Large Eruptions of Vulcano Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
Smithsonian Collections Search the Smithsonian's NMNH Department of Mineral Sciences collections database. Go to the "Search Rocks and Ores" tab and use the Volcano Name drop-down to find samples.