What kind of volcano is vulcano

Simkin, T. Skip to main content. Toggle menu Go to search page. Search Field. You are here Home. Elevation: 1, feet m Vulcano is a volcanic island and the southernmost of the Aeolian Islands.

Active fumaroles are now concentrated near the Gran Cratere on Fossa. Keller, J. Italiana Min. Krafft, M. Images of Volcanoes To VolcanoWorld. Latitude DD :. Longitude dd :. Elevation m :. Google Maps:. More Images:. Lavas with low silica contents have low viscosities and flow freely, allowing any gas bubbles to escape readily, while lavas with high silica contents are more viscous resistant to flow , so that any trapped gases cannot escape gradually.

Mount Garibaldi, a potentially active volcano in southwest British Columbia, located within 30 km of the towns of Whistler and Squamish. How the silica and gas content of lava affect volcano eruptive behaviour. Skip to main content Skip to "About this site". What is a volcano? Since then, a sharp change has been observed, with ground inflation and significant increases in the maximum temperature and water concentration of emitted fluids. The most recent April 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. Martini, M. 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 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 A new linear zone of high-pressure gas emission has developed roughly parallel to the large fissure that formed after on the N crater wall.

Fumarolic activity from scattered vents on the upper N flank seemed to have increased since November , 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. 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 Courtesy of A.

Harris, Open Univ. 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. 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. 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 visit BGVN 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 Fumaroles were also active at Gran Cratere in October 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.

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 and April showed a significant decrease in temperatures. Fumarole emissions during this period exhibited increased H 2 O and CO 2 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 and April La Pira 4, Florence, Italy. Fumarolic activity, vigorous in the late s and through , notably diminished in BGVN and 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 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.

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 midth century. During the night of May, several new fissures, m long and 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. During the same night, pre-existing fissures widened by a few centimeters.

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.

Fumarole temperatures therefore showed decreasing trends, but maximum temperatures remained high. The decrease was strongest at the rim fumaroles.

Table 4. Courtesy of C. All measurements were taken at the same locations as those made in Temperatures at each point were also taken on three successive days; deviations in were. Fumarolic emissions observed by Boris Behncke during April from the Fossa Grande crater appeared more voluminous and denser than during 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.

Periodic observations of the chemical composition of fumarolic gases have been made at Vulcano since 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 Table 5 shows the trend in chemical composition of gases emitted by fumaroles on the rim and inside the crater during For fumaroles on the rim, percentages of typical magmatic species such as SO 2 , H2, and CO increased during ; 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, Courtesy of M. 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 revealed low fumarole temperatures and less abundant emissions. This was confirmed by Behncke during June-July and October when fumarolic emissions were the lowest since This compilation of synonyms and subsidiary features may not be comprehensive.

Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided. The word volcano is derived from Vulcano stratovolcano in Italy's Aeolian Islands.

Vulcano was constructed during six stages over the past , years. Two overlapping calderas, the 2. La Fossa cone, active throughout the Holocene and the location of most 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 is a low, roughly circular peninsula on the northern tip of Vulcano that was formed as an island beginning more than 2, years ago and was connected to the main island in about CE.

Vulcanello is capped by three pyroclastic cones and was active intermittently until the 16th century. Explosive activity took place at the Fossa cone from to The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Eruptions of the last years at Vulcano and Vulcanello Aeolian Islands, Italy dated by high-accuracy archeomagnetism.

Phys Earth Planet Int , Imaging and modelling the subsurface structure of volcanic calderas with high-resolution aeromagnetic data at Vulcano Aeolian Islands, Italy.

Bull Volcanol , Acta Vulc , 1: Assessment of a shallow magmatic system: the eruption, Vulcano Island, Italy. Livelli di allerta. Sono individuati sulla base della combinazione di parametri di monitoraggio e di dati relativi a eventuali eventi in corso. In particolare:. Dichiarazione dei livelli di allerta. Il Dipartimento della protezione civile condivide tutte queste informazioni con la struttura di protezione civile della Regione Siciliana che, soprattutto in relazione a scenari di impatto locale, ha il compito di allertare le strutture territoriali di protezione civile e adottare eventuali misure in risposta alle situazioni emergenziali.

Passaggio di livello di allerta. Rilascio di gas tossici.