Italian Volcanoes Explained: Etna, Vesuvius, Stromboli, Campi Flegrei and Italy’s Active Volcanic Regions

Why Does Italy Have So Many Volcanoes?

Italy has volcanoes because it occupies one of the most geologically complicated collision zones on the planet.
The Mediterranean region sits between the broad African and Eurasian tectonic plates, but the boundary between
them is not a single clean line. It is divided into smaller plates, rotating crustal blocks, deep ocean basins,
mountain belts, faults and fragments of subducting oceanic crust.

For tens of millions of years, Africa has moved generally northward toward Eurasia. This convergence helped form
the Alps, Apennines and other Mediterranean mountain systems. In southern Italy, remnants of oceanic lithosphere
have descended into the mantle beneath the Calabrian region and the Tyrrhenian Sea.

Water and other volatile substances released from descending crust can promote melting in the mantle above the
subduction zone. The resulting magma rises through weaknesses in the crust and may collect in underground
reservoirs before erupting at the surface.

Subduction is only part of the story. Parts of Italy and the Tyrrhenian region are also being stretched. This
extension creates faults, thins the crust and provides pathways through which magma can rise. The interaction
between compression, subduction, extension and regional faulting helps explain why Italian volcanoes occur in
several separate provinces rather than in one continuous line.

Italy’s volcanoes therefore cannot all be explained by one simple mechanism. Etna, the Aeolian Islands, Vesuvius,
Campi Flegrei and the volcanic districts of central Italy have different magma compositions, geological histories
and relationships with the regional tectonic system.

Italy’s Mediterranean Tectonic Setting

The central Mediterranean contains a patchwork of tectonic elements. These include the African Plate, Eurasian
Plate, Adriatic or Apulian block, Ionian oceanic crust, Calabrian Arc, Apennine mountain chain and the
back-arc basin of the Tyrrhenian Sea.

The Calabrian Arc curves around the southern end of mainland Italy and northeastern Sicily.
Beneath this region, a slab of Ionian oceanic lithosphere descends steeply into the mantle. The slab’s retreat has
contributed to extension behind the volcanic arc and to the opening of the Tyrrhenian Sea.

This geological configuration helped generate the volcanic islands of the Aeolian archipelago, including
Stromboli, Vulcano, Lipari and Panarea. It also influenced submarine volcanism in the southern Tyrrhenian basin.

Mount Etna lies south of the main Aeolian arc and has a more debated tectonic origin. Its magma production appears
to involve interaction among regional faults, the edge of the subducting slab, mantle upwelling and the complex
boundary between eastern Sicily and the Ionian domain.

Farther north, the volcanoes of the Naples region—including Vesuvius, Campi Flegrei and Ischia—formed within a
zone affected by crustal extension along the western side of the Apennines. Their magmas evolved beneath a region
where continental crust, older subduction processes and Tyrrhenian extension interact.

Central Italy contains older volcanic districts around Rome, Lazio and Tuscany. These systems include large
calderas, crater lakes, lava plateaus and extinct or dormant centers. Although they are generally much less active
than Etna or Stromboli, their geology records repeated episodes of explosive and effusive volcanism.

Major Volcanic Regions of Italy

Italian volcanoes can be divided into several broad geographical provinces. Each province contains volcanoes with
distinctive ages, magma compositions and eruption styles.

Types of Italian Volcanoes

Italy contains nearly every major type of volcanic landform found in subduction-related and extensional settings.
The shape of a volcano reflects its magma, eruption frequency, structural history and interaction with water.

Stratovolcanoes

Stratovolcanoes are large, steep-sided volcanoes built from alternating layers of lava, ash, scoria and other
fragmented material. Etna, Vesuvius and Stromboli are all broadly stratovolcanic, although each has a very
different shape and eruption pattern.

Calderas

Calderas are large depressions formed when the ground collapses after magma is withdrawn from a shallow reservoir.
Campi Flegrei is a vast caldera rather than a classic cone. Pantelleria and several central Italian volcanic
districts also contain major collapse structures.

Lava Domes

Lava domes form when viscous magma accumulates close to a vent instead of flowing easily away. Dome growth can be
hazardous because unstable sections may collapse and generate pyroclastic density currents.

Shield-Like Lava Complexes

Although Etna is commonly called a stratovolcano, its broad lower slopes and repeated fluid lava flows give parts
of the volcanic edifice shield-like characteristics. Its overall structure reflects overlapping eruptive centers,
flank vents and repeated episodes of collapse and rebuilding.

Maar Craters and Crater Lakes

Explosive interaction between magma and groundwater can excavate broad, low-relief craters called maars. Several
central Italian lakes occupy volcanic craters or caldera depressions.

Submarine Volcanoes

Much of Italy’s volcanic landscape continues below sea level. Submarine eruptions may produce pillow lava,
hydrothermal vents, pumice rafts, gas emissions or temporary islands when eruptive material reaches the surface.

Which Italian Volcanoes Are Active?

The word active does not mean that a volcano is erupting continuously. It generally describes a
volcanic system that has erupted during geologically recent time or continues to show signs of magma, gas or
hydrothermal activity.

Italy’s most visibly active volcanoes are Mount Etna and Stromboli. Both erupt frequently, but their activity can
shift rapidly from relatively mild emissions to powerful explosions, lava fountains or lava flows.

Other active or potentially active systems include:

• Vesuvius, which last erupted in 1944;
• Campi Flegrei, where earthquakes and ground deformation reflect continuing unrest;
• Vulcano, which last erupted in the nineteenth century but remains strongly fumarolic;
• Ischia, a resurgent volcanic island with geothermal activity;
• Pantelleria, which has experienced geologically recent eruptions;
• submarine volcanic systems in the Tyrrhenian Sea and Sicily Channel.

Some central Italian systems have been quiet for tens of thousands of years yet retain geothermal activity,
carbon-dioxide emissions or geological evidence of comparatively recent eruptions. Their classification can
depend on the timescale and criteria used by individual studies.

Volcanoes of Sicily and the Aeolian Islands

Sicily and the nearby Aeolian Islands form Italy’s most continuously active volcanic region. Mount Etna dominates
the eastern coast of Sicily, while the Aeolian chain curves across the southern Tyrrhenian Sea north of the island.

The seven principal Aeolian Islands are Alicudi, Filicudi, Salina, Lipari, Vulcano, Panarea and Stromboli. Each
island represents the exposed summit or remnants of a much larger volcanic structure rising from the seafloor.

The archipelago contains active craters, extinct cones, collapsed calderas, obsidian flows, underwater gas vents,
fumaroles, hot springs and lava domes. Stromboli and Vulcano are the best-known active systems, but volcanic and
hydrothermal processes occur across the broader island chain.

The terms Strombolian eruption and Vulcanian eruption were both derived from
Italian volcanoes. These names are now used worldwide to describe two contrasting styles of explosive activity.

Mount Etna: Europe’s Giant Active Volcano

Mount Etna rises above the eastern coast of Sicily between Catania and the Strait of Messina. It
is the highest active volcano in continental Europe and one of the most frequently erupting volcanoes on Earth.
Its summit elevation changes as eruptions construct new cones or destroy parts of the crater area.

Etna’s volcanic history extends back more than half a million years. Early eruptions occurred in a marine or
coastal environment before volcanic activity gradually migrated and built the enormous complex visible today.
During approximately the last hundred thousand years, Etna developed the broad conical shape that now dominates
northeastern Sicily.

The modern volcano is not a single simple cone. It consists of overlapping eruptive centers, summit craters,
hundreds of flank cones, ancient collapse structures and layers of lava and pyroclastic material accumulated
during thousands of eruptions.

Etna’s Summit Craters

Etna’s summit area contains several principal crater structures that can change through time as vents open,
collapse or merge. The best-known summit areas include the Northeast Crater, Bocca Nuova, Voragine and the
Southeast Crater complex.

Summit activity may involve gas emissions, ash explosions, Strombolian bursts, lava fountains and lava overflows.
Some eruptive episodes remain confined near the summit, while others feed lava flows that descend into the
uninhabited upper slopes.

Etna’s Flank Vents

Some of Etna’s most consequential eruptions begin when fractures open on the volcano’s flanks. Magma can travel
laterally through underground dikes and emerge far below the summit. These flank eruptions may threaten towns,
roads, ski facilities, forests, farms and communication infrastructure.

Hundreds of cinder cones dot Etna’s slopes. Many formed during relatively short-lived flank eruptions that
produced lava fountains, scoria and extensive lava flows.

The Valle del Bove

The eastern side of Etna is cut by the enormous Valle del Bove, a horseshoe-shaped depression
created by repeated structural collapse and erosion. The valley acts as a natural containment area for many lava
flows from the summit and upper eastern flank.

Its steep walls expose layers from older volcanic edifices, allowing scientists to reconstruct parts of Etna’s
complicated geological evolution.

How Does Mount Etna Erupt?

Etna produces a wide range of eruption styles, from quiet lava effusion to spectacular lava fountains and
explosive ash columns. Activity can occur at summit craters or from fissures that open on the volcano’s flanks.

Strombolian Explosions

Gas bubbles rising through the magma can burst at open vents, throwing glowing fragments, lava bombs and scoria
into the air. Repeated bursts may continue for hours, days or much longer.

Lava Fountains

During more intense episodes, jets of incandescent lava can rise hundreds of meters above the crater. These
paroxysmal events may generate rapidly growing eruption columns, widespread ashfall and lava flows from overflowing
crater rims.

Effusive Lava Flows

Etna’s basaltic lava is generally more fluid than the silica-rich magma associated with many highly explosive
caldera systems. Lava can travel through open channels or insulated lava tubes, allowing flows to extend far from
their vents.

Explosive Ash Emissions

Even though Etna is famous for lava, it can also generate powerful explosive activity. Ash plumes may disrupt
aviation, close airports, reduce visibility and cover roads, roofs, crops and vehicles across eastern Sicily.

Historic Etna Eruptions

Etna has one of the world’s longest documented eruption histories. Ancient Greek and Roman writers described its
activity, and geological evidence preserves eruptions extending much further into the past.

The 1669 eruption is among Etna’s most famous historical events. Fissures opened on the southern flank and
produced enormous lava flows that buried villages and reached the walls of Catania before entering the sea.

Other major episodes occurred in 1928, when lava destroyed much of Mascali, and during the long 1991–1993
eruption, when lava threatened the town of Zafferana Etnea.

Mount Etna Hazards

Etna’s frequent activity creates several hazards, although their severity depends strongly on vent location,
eruption intensity, wind direction and the duration of lava effusion.

Compared with Vesuvius or Campi Flegrei, Etna more commonly produces basaltic lava flows and moderate explosive
activity. However, this does not make it harmless. Its enormous size, frequent eruptions and proximity to densely
populated communities create persistent risk.

Stromboli: The Lighthouse of the Mediterranean

Stromboli forms the northeasternmost island of the Aeolian archipelago. Most of the volcanic
edifice lies beneath the Tyrrhenian Sea, with only its summit rising above the water as a steep, cone-shaped island.

Stromboli is one of the few volcanoes on Earth known for persistent eruptive activity. Small explosions commonly
occur from several vents on a crater terrace near the summit, producing incandescent bursts that can be visible
from boats and neighboring islands at night.

This long-lived glow earned Stromboli the nickname Lighthouse of the Mediterranean. Sailors used
its summit explosions as a natural navigational landmark long before modern lighthouse systems existed.

The Crater Terrace

Stromboli’s active vents occupy a crater terrace below the highest point of the island. The number, shape and
position of active vents can change as explosions build cones, open fractures or cause sections of the crater area
to collapse.

Most erupted material falls onto the upper slopes or is directed toward the northwest side of the island, where
the steep Sciara del Fuoco descends from the crater area into the sea.

The Sciara del Fuoco

The Sciara del Fuoco is a broad collapse scar and debris slope that channels lava flows, rockfalls and hot
volcanic fragments toward the coast. Material accumulating on the slope can become unstable and slide into the
sea.

Although the Sciara often directs eruptive material away from the island’s main settlements, it can also generate
dangerous coastal waves if a large landslide or pyroclastic flow enters the water.

What Is a Strombolian Eruption?

The term Strombolian eruption describes the characteristic intermittent explosions observed at
Stromboli. Gas bubbles rise through magma in the conduit, expand and burst near the surface, ejecting incandescent
lava fragments, bombs and lapilli.

Typical Strombolian activity is often relatively low in intensity. Individual explosions may last only seconds and
be separated by intervals of several minutes. However, the apparent regularity can be deceptive.

Stromboli can shift into much more powerful activity, including major explosions, paroxysms, high eruption columns,
pyroclastic density currents and lava flows. These stronger events may occur with limited warning and can affect
summit areas, slopes, settlements and surrounding waters.

Stromboli Volcano Hazards

Stromboli’s persistent activity attracts visitors, but it also creates the dangerous impression that its behavior
is predictable. Ordinary explosions can be punctuated by rare but violent events.

Ballistic Blocks and Bombs

Powerful explosions can eject large fragments far beyond the active vents. Ballistic material poses one of the
greatest threats to people near the summit.

Pyroclastic Density Currents

During strong eruptions, hot mixtures of ash, gas and rock may descend the Sciara del Fuoco and travel across the
sea surface for a limited distance.

Lava Flows

Lava overflows commonly move down the Sciara del Fuoco. While this channel generally directs flows away from the
main settlements, collapsing lava fronts can generate explosions, rockfalls and small waves.

Landslides and Tsunamis

Stromboli’s steep flanks are structurally unstable. In December 2002, part of the Sciara del Fuoco collapsed into
the sea and generated waves that damaged coastal areas around the island.

Volcanic Ash and Fires

Major explosions can spread hot fragments and ash over the island. Incandescent material may ignite dry
vegetation, particularly during summer.

Volcanic Gases

Stromboli releases gas continuously. Wind conditions can concentrate sulfur-rich emissions around the summit,
crater terrace or downwind slopes.

How Etna and Stromboli Are Monitored

Mount Etna and Stromboli are monitored by the
Istituto Nazionale di Geofisica e Vulcanologia, commonly known as INGV. Monitoring combines
seismic instruments, ground-deformation measurements, gas observations, thermal cameras, webcams, satellites and
field surveys.

Seismic Monitoring

Seismometers detect volcanic earthquakes, tremor, explosions and fracturing associated with moving magma or gas.
Changes in the strength and location of tremor can reveal movement within the shallow plumbing system.

Ground Deformation

GPS stations, tiltmeters and satellite radar measure inflation, deflation and movement of volcanic flanks. These
data are especially important on Etna, where magma intrusion and slow eastward flank motion interact.

Gas Monitoring

Instruments measure sulfur dioxide, carbon dioxide and other gases released from craters, soil and fumaroles.
Changes in gas composition or output can indicate that fresh magma is rising.

Thermal Cameras and Webcams

Visible-light and infrared cameras track explosions, lava fountains, lava flows and heat anomalies. They are
particularly valuable when bad weather, darkness or hazardous conditions prevent direct observation.

Satellite Observations

Satellites can detect thermal activity, ash plumes, sulfur dioxide clouds and surface deformation over large
areas. This information supports aviation warnings and complements instruments installed directly on the volcanoes.

Mount Vesuvius: The Volcano That Destroyed Pompeii

Mount Vesuvius rises east of Naples above one of the most densely populated volcanic landscapes
in the world. Its outline is instantly recognizable: the younger cone of Vesuvius sits partly inside the remains
of an older volcanic structure known as Monte Somma. Together, they form the
Somma–Vesuvius volcanic complex.

Vesuvius is famous for the eruption of AD 79 that buried Pompeii, Herculaneum and other Roman communities.
That catastrophe was not an isolated geological accident. The volcano has produced repeated explosive eruptions,
lava flows, ashfall and pyroclastic density currents throughout its history.

Vesuvius last erupted in 1944. Since then, it has remained quiet at the surface, but quiet does not mean extinct.
Its eruptive history shows a pattern in which periods of frequent activity can be separated by longer intervals
of repose. Some long repose periods have ended with powerful explosive eruptions.

The Structure of Somma–Vesuvius

The steep ridge north and northeast of the modern cone is part of Monte Somma, the remnant of an older volcanic
edifice that experienced major collapse. The younger Gran Cono of Vesuvius grew within the collapse depression.

This nested structure records repeated cycles of volcano construction, explosive destruction and rebuilding.
Layers exposed in quarries and natural outcrops preserve pumice, ash, lava and pyroclastic deposits from numerous
eruptions.

The present summit crater is only the youngest surface feature of a much larger underground volcanic system.
Magma may be stored at different depths before rising through fractures toward the surface.

Vesuvius Eruption History

Vesuvius has produced eruptions ranging from lava effusion and moderate explosions to major Plinian events.
Archaeological and geological studies reveal that communities around the volcano have repeatedly been affected
by ashfall, pyroclastic currents and landscape change.

The Avellino Eruption

Long before Pompeii was destroyed, Vesuvius produced a major Bronze Age eruption commonly known as the
Avellino eruption. It dispersed pumice and ash across the region and generated pyroclastic
currents that affected prehistoric settlements.

Excavations have revealed abandoned villages, footprints and evidence of emergency flight. These discoveries show
that large populations were exposed to Vesuvius thousands of years before the Roman period.

The AD 79 Eruption

The most famous eruption began in AD 79 after a long period without major surface activity. A towering eruption
column rose above the volcano and spread pumice and ash across the Bay of Naples region.

Winds carried much of the initial pumice fallout toward Pompeii and settlements southeast of the volcano.
Accumulating material buried streets and buildings, obstructed movement and caused roofs to collapse.

Herculaneum, located west of the volcano, received less early pumice fallout but was later overwhelmed by
pyroclastic density currents. These hot, fast-moving clouds of ash, gas and rock buried the town beneath thick
deposits.

As the eruption column became unstable, repeated collapses generated pyroclastic currents that swept across the
surrounding landscape. These currents were responsible for many of the deaths and for the final burial of Pompeii.

Pliny the Younger and the Birth of “Plinian”

Much of the written account of the AD 79 eruption comes from letters by Pliny the Younger, who
observed the eruption from across the Bay of Naples. He described a vast cloud rising like a tree with spreading
branches.

His uncle, Pliny the Elder, commanded a Roman fleet and crossed the bay during the disaster. He died near Stabiae.
Modern volcanologists later adopted the term Plinian eruption for sustained, powerful explosive
eruptions that generate high columns of gas, ash and pumice.

The 1631 Eruption

After centuries of relative quiet, Vesuvius erupted violently in December 1631. The event generated ashfall,
pyroclastic currents, lahars and flooding around the volcano.

The eruption caused widespread destruction and marked the beginning of a new period of more frequent activity.
It also demonstrated a recurring Vesuvius pattern: a long repose interval followed by a dangerous explosive
reawakening.

Activity from the Seventeenth to Twentieth Centuries

Following 1631, Vesuvius entered a prolonged phase characterized by repeated summit eruptions, lava flows,
Strombolian explosions and occasional stronger explosive events.

The volcano became an important destination for early geologists, naturalists and travelers. Observations made at
Vesuvius helped shape the emerging science of volcanology.

The 1906 Eruption

The April 1906 eruption was one of the largest Vesuvius events of the twentieth century. It produced intense
explosions, heavy tephra fall and structural damage in towns around the volcano.

Ash and lapilli caused roof collapses, while agricultural areas were severely affected. The eruption illustrates
how even communities outside zones threatened by pyroclastic currents may face dangerous ash accumulation.

The Last Eruption: 1944

Vesuvius last erupted during March 1944, while southern Italy was occupied by Allied forces during the Second
World War. Lava flows damaged nearby settlements, and ashfall affected military airfields and aircraft.

After the eruption ended, the volcano entered its present repose period. The disappearance of frequent summit
eruptions changed how generations of residents perceived the volcano, but its geological ability to erupt did
not disappear.

Vesuvius Hazards

Vesuvius can produce several hazards simultaneously. The severity of a future eruption will depend on its size,
vent conditions, wind direction, rainfall and the timing of evacuations.

Vesuvius Red and Yellow Planning Zones

Italian emergency planning distinguishes between areas exposed to different volcanic hazards. The
red zone identifies communities that could be threatened by pyroclastic density currents and
other immediately life-threatening effects.

The yellow zone covers a wider area where substantial ashfall may occur. The exact distribution
of ash during an eruption would depend strongly on wind direction and eruption intensity.

Evacuation planning for Vesuvius is based on moving people out of the red zone before hazardous eruptive
phenomena begin. Waiting until a large eruption is visibly underway would leave too little time for a safe
large-scale evacuation.

How Is Vesuvius Monitored?

Vesuvius is monitored by the Osservatorio Vesuviano, the Naples branch of the Italian National
Institute of Geophysics and Volcanology. Established in the nineteenth century, the Vesuvius Observatory is often
described as the world’s oldest volcano observatory.

Modern surveillance uses instruments distributed around the volcanic complex and across the wider Campanian
region.

• Seismometers record volcanic and tectonic earthquakes.
• GNSS stations measure changes in ground position.
• Tiltmeters detect subtle changes in slope.
• Gravimetric measurements help identify changes in subsurface mass distribution.
• Gas monitoring tracks emissions from soil and fumarolic areas.
• Thermal observations detect changes in heat flow.
• Satellite radar measures broad patterns of deformation.

Monitoring does not provide a perfect eruption clock. Scientists look for combinations of changes that could
indicate magma migration or increasing pressure. A future crisis would be assessed through multiple datasets,
geological models and official alert-level procedures.

Campi Flegrei: The Restless Caldera Beneath the Bay of Naples

West of Naples lies one of Europe’s most complex and closely watched volcanic systems:
Campi Flegrei, also called the Phlegraean Fields.

Campi Flegrei is not a single cone. It is a broad caldera containing numerous craters, vents, fumaroles, thermal
areas and densely populated communities. Parts of the caldera extend beneath the Gulf of Pozzuoli.

Pozzuoli, Bacoli, Monte di Procida and western districts of Naples occupy this volcanic landscape. Roads,
neighborhoods, archaeological sites and coastal infrastructure sit directly above or beside vents formed during
past eruptions.

How the Campi Flegrei Caldera Formed

Campi Flegrei developed through repeated explosive eruptions and episodes of caldera collapse. The present
landscape records overlapping structures rather than one perfectly defined circular depression.

Two especially large eruptions dominate discussions of the caldera’s history: the
Campanian Ignimbrite eruption and the later Neapolitan Yellow Tuff eruption.

Both events released enormous quantities of magma and spread pyroclastic deposits across a wide region. Collapse
of the ground above partly emptied magma reservoirs helped shape the caldera.

Later eruptions occurred from numerous vents within the caldera, forming cones, tuff rings, lava domes and crater
lakes. A future eruption would not necessarily emerge from the site of the most recent vent.

The Campanian Ignimbrite Eruption

The Campanian Ignimbrite was one of the largest explosive eruptions in Europe during the late
Quaternary period. It occurred tens of thousands of years ago and generated widespread ashfall and pyroclastic
deposits.

Ignimbrite is rock formed from deposits of hot pyroclastic density currents. During a very large eruption, such
currents can spread outward across valleys and terrain, leaving thick sheets of ash, pumice and fragmented rock.

Fine ash from the Campanian Ignimbrite eruption traveled far beyond southern Italy. Deposits associated with the
event provide an important chronological marker in archaeological and geological sequences across parts of Europe
and the Mediterranean.

The eruption occurred during a period of major environmental and human change, leading researchers to study
possible links among volcanic effects, climate variability and prehistoric populations. Such relationships remain
scientifically complex and should not be reduced to a single-cause explanation.

The Neapolitan Yellow Tuff Eruption

The later Neapolitan Yellow Tuff eruption was another major caldera-forming event. Its deposits
are widespread around Naples and have strongly influenced the region’s geology, architecture and underground
landscape.

The yellow volcanic tuff was cut and quarried for construction over many centuries. Cavities created through
extraction became part of the extensive system of tunnels, cisterns and underground spaces beneath Naples.

Following this eruption, volcanic activity continued from multiple vents inside the caldera. The younger landscape
includes Astroni, Agnano, Solfatara, Monte Nuovo and several partially submerged volcanic structures.

The 1538 Monte Nuovo Eruption

The most recent confirmed eruption of Campi Flegrei occurred in 1538. After earthquakes and significant ground
uplift, a vent opened near the town of Pozzuoli.

Explosive activity built a new tuff cone over several days. The cone became known as
Monte Nuovo, meaning “New Mountain.”

The eruption provides a striking reminder that new vents can open within populated parts of a caldera. A future
Campi Flegrei eruption would not be expected to occur from a permanent summit crater because no such central cone
exists.

Monte Nuovo also demonstrates the link between deformation and eruption. Ground uplift preceded vent opening,
although not every episode of uplift at Campi Flegrei has led to an eruption.

What Is Bradyseism at Campi Flegrei?

Bradyseism is the slow uplift or subsidence of the ground in a volcanic area. The word comes from
Greek roots referring to slow movement.

Campi Flegrei has experienced repeated cycles of uplift and sinking over centuries. Evidence is visible at the
ancient Roman marketplace of Pozzuoli, commonly called the Temple of Serapis, where marine-boring organisms left
marks on columns that moved above and below sea level.

Modern uplift may result from changes in pressure within the hydrothermal system, movement of hot fluids and gases,
deep magma input or interaction among these processes.

As the ground rises, rocks in the shallow crust can fracture and produce earthquakes. The strongest seismicity is
often concentrated around Pozzuoli, Solfatara, Pisciarelli, Agnano and the Gulf of Pozzuoli.

Does Ground Uplift Mean an Eruption Is Imminent?

No. Ground uplift is evidence of unrest, but it does not automatically mean that magma will reach the surface.
Campi Flegrei experienced major unrest during the twentieth century without an eruption.

Scientists must determine whether observed changes are driven mainly by hydrothermal fluids, gas pressure, magma
movement or a combination of mechanisms. Even with dense monitoring, significant uncertainty remains.

Solfatara and Pisciarelli

Solfatara is a volcanic crater within Campi Flegrei known for fumaroles, sulfur deposits, hot
ground and gas emissions. It was historically visited as a natural curiosity and scientific site.

Nearby Pisciarelli has become an important focus of monitoring because it contains vigorous
fumaroles, bubbling mud, high ground temperatures and changing hydrothermal activity.

Carbon dioxide, water vapor, hydrogen sulfide and other gases move through fractures from the subsurface.
Concentrations can become hazardous, particularly in enclosed or low-lying areas where heavy carbon dioxide may
accumulate.

Thermal cameras, gas instruments, field surveys and drone observations help scientists document changes in these
hydrothermal zones.

Campi Flegrei Hazards

Campi Flegrei presents an unusual risk because potential vents are distributed across a broad caldera occupied by
dense urban development. The exact position of a future eruption cannot be known far in advance.

Campi Flegrei Emergency Planning

National emergency planning defines zones based on anticipated hazards. The red zone includes areas most exposed
to pyroclastic density currents, while the yellow zone identifies areas that may receive substantial volcanic ash.

Because a future vent could open in different parts of the caldera, planning must account for several possible
eruption locations rather than a single summit crater.

Alert levels and operational phases are based on monitoring data and scientific assessments. They communicate
increasing unrest, but no alert system can eliminate uncertainty.

Residents should understand local civil-protection plans, assembly areas and official information channels before
an emergency develops.

Ischia: A Resurgent Volcanic Island

Ischia lies at the western side of the Bay of Naples. It is famous for beaches, spas, hot springs
and steep green landscapes, but the island is also an active volcanic system.

Much of Ischia consists of a resurgent caldera. After a major explosive eruption and collapse, part of the caldera
floor was gradually pushed upward by forces beneath the island.

The uplifted central block forms Monte Epomeo, the island’s highest point. Monte Epomeo is not a
simple volcanic cone; it is largely a raised block of volcanic deposits shaped by faulting, erosion and landslides.

The Green Tuff Eruption

A major explosive event produced the deposits known as the Green Tuff of Monte Epomeo. These
deposits are an important part of the island’s geological structure and record a large caldera-forming eruption.

Later volcanism occurred from vents across the island, producing lava flows, domes, craters and pyroclastic
deposits.

The Arso Eruption

Ischia’s most recent eruption occurred in the early fourteenth century. Lava issued from a vent in the eastern
part of the island and formed the Arso lava flow, which reached the coast near present-day Ischia
Porto.

This event is geologically recent and confirms that Ischia is not an extinct volcanic island.

Hot Springs and Fumaroles

Ischia’s thermal spas are supplied by groundwater heated within the volcanic system. Hot springs and fumaroles
show that substantial heat remains beneath the island.

Geothermal activity is economically valuable, but it also indicates continuing circulation of hot fluids and gases
through fractured rock.

Ischia Volcanic, Earthquake and Landslide Hazards

Ischia faces a combination of volcanic, seismic and slope-instability hazards. Even during periods without
eruption, earthquakes and landslides can cause severe local damage.

Shallow Earthquakes

Earthquakes beneath northern Ischia are often shallow. A moderate-magnitude event at shallow depth can generate
intense local shaking because the seismic energy reaches the surface over a short distance.

The town of Casamicciola has experienced destructive earthquakes, including the major 1883 disaster. More recent
seismicity has reinforced the importance of building vulnerability and local geology.

Landslides

Steep slopes, fractured volcanic rock, loose deposits, heavy rainfall and development on unstable terrain create
significant landslide risk. Debris flows can move rapidly through channels and densely built neighborhoods.

Future Eruptive Hazards

A future eruption could involve lava flows, explosions, ashfall, ballistic fragments or pyroclastic density
currents, depending on vent location and magma-water interaction.

Because vents have opened in different parts of the island, volcanic hazard is not confined to one summit.

Vulcano Island: The Volcano That Named Them All

The island of Vulcano lies at the southern end of the Aeolian archipelago, separated from Lipari
by a narrow channel. Its name ultimately gave rise to the modern words volcano and volcanic.

Ancient Romans associated the island’s smoke, heat and sulfurous gases with the forge of Vulcan, the god of fire
and metalworking.

Vulcano is a composite volcanic system rather than a single cone. Its principal structures include the older
caldera of Piano, the Fossa cone, Vulcanello and offshore volcanic features.

La Fossa Crater

The large crater commonly visited on Vulcano is known as La Fossa or Gran Cratere. Fumaroles
around the crater rim release hot, sulfur-rich gases that can form brightly colored mineral deposits.

Gas concentrations and temperatures may change during unrest. Access restrictions are therefore based on safety
assessments rather than on whether visible eruptions are occurring.

Vulcanello

Vulcanello began as a separate volcanic island north of Vulcano. Repeated eruptions built cones and lava flows,
eventually connecting it to the main island by a low isthmus.

The landform demonstrates how coastal volcanism can rapidly reshape shorelines and create new territory.

What Is a Vulcanian Eruption?

The term Vulcanian eruption was inspired by the explosive nineteenth-century activity of Vulcano.
It describes short, powerful explosions caused when gas pressure breaks through a blocked or viscous magma column.

Vulcanian explosions commonly generate dense ash clouds and eject blocks and bombs around the vent. They may also
produce pyroclastic density currents if part of the eruption cloud collapses.

This eruption style is generally more explosive than ordinary Strombolian activity, although real eruptions can
shift between styles and cannot always be placed in a single category.

The 1888–1890 Vulcano Eruption

Vulcano’s most recent eruption occurred between 1888 and 1890. Repeated explosions from La Fossa threw blocks,
bombs and ash around the crater.

Observations of the eruption helped volcanologists define the Vulcanian eruption style. Large bread-crust bombs,
whose cracked surfaces formed as their interiors expanded, became particularly associated with the event.

Although Vulcano has not erupted since 1890, it remains active. Fumaroles, ground temperatures, gas emissions and
seismicity are continually monitored.

Hydrothermal and Gas Hazards

Volcanic unrest does not require lava or ash to become dangerous. Increased carbon-dioxide emissions can affect
low-lying areas, buildings and poorly ventilated spaces.

Carbon dioxide is colorless and odorless. Because it is denser than air, it may collect near the ground and
displace breathable oxygen.

Sulfur dioxide and hydrogen sulfide can irritate the eyes and respiratory system, while fumarolic ground may be
dangerously hot or structurally unstable.

Lipari: Obsidian, Pumice and Explosive Volcanism

Lipari is the largest of the Aeolian Islands and preserves a long history of volcanic activity.
Its landscape contains lava domes, pumice deposits, obsidian flows, craters and hydrothermal features.

Lipari’s magmas have often been richer in silica than the basaltic magma typical of Etna. Silica-rich magma is
more viscous and can trap gas, increasing the potential for explosive eruptions.

Obsidian

Obsidian is natural volcanic glass formed when silica-rich lava cools rapidly. Lipari obsidian was widely traded
across the prehistoric Mediterranean and used to make sharp tools and blades.

Pumice

Pumice forms when gas-rich magma expands and solidifies into highly porous volcanic rock. Large pale deposits on
Lipari record explosive eruptions and became the basis of an important mining industry.

Recent Geological Activity

Lipari has not erupted in modern historical time, but geologically young lava domes and obsidian flows demonstrate
that its volcanic system remained active during the Holocene.

Panarea and Its Submarine Hydrothermal Field

Panarea is the smallest of the principal inhabited Aeolian Islands. Much of its volcanic complex
lies beneath the sea and includes nearby islets, submerged craters and hydrothermal vents.

Gas bubbles can be observed rising through shallow coastal waters in areas such as Bottaro and Lisca Bianca.
These emissions are connected to an active hydrothermal system.

Episodes of increased gas release have demonstrated that hydrothermal activity can change suddenly. Carbon
dioxide and other gases may affect seawater chemistry, marine organisms and people close to strong emission points.

Panarea is an important natural laboratory for studying volcanic gas release beneath shallow seawater and the
effects of carbon dioxide on marine ecosystems.

Salina, Filicudi and Alicudi

The western and central Aeolian Islands preserve older volcanic landscapes that have been deeply modified by
erosion, landslides and marine processes.

Salina

Salina contains two prominent volcanic peaks, Monte Fossa delle Felci and Monte dei Porri. Its name is associated
with a former salt lake at Lingua.

The island’s volcanic soils support vineyards and agriculture, illustrating how weathered ash and lava can produce
fertile terrain.

Filicudi

Filicudi consists of overlapping volcanic centers and steep eroded slopes. Offshore sea stacks and submerged
structures reveal the continuing effects of erosion and flank collapse.

Alicudi

Alicudi is the westernmost Aeolian Island. Its simple conical profile represents the exposed summit of a much
larger volcanic edifice rising from the seafloor.

These islands are not presently erupting, but their rocks help reconstruct the migration and evolution of
volcanism across the Aeolian arc.

Pantelleria: Italy’s Peralkaline Volcanic Island

Pantelleria lies in the Sicily Channel between Sicily and Tunisia. It is the exposed summit of a
large submarine volcanic system positioned within a zone where the crust is being stretched.

The island is famous for calderas, dark lava flows, obsidian, fumaroles, hot springs and unusual
peralkaline magmas.

What Is Peralkaline Magma?

Peralkaline magmas contain relatively high proportions of sodium and potassium compared with aluminum. They may
evolve into silica-rich compositions capable of producing fluid lava flows, obsidian and explosive pumice eruptions.

The volcanic rock type pantellerite takes its name from Pantelleria. It is a dark, silica-rich,
peralkaline volcanic rock found in only a limited number of volcanic regions worldwide.

The Pantelleria Calderas

Much of central Pantelleria lies within large collapse structures formed by powerful explosive eruptions.
The younger Cinque Denti caldera partly overlaps an older caldera.

Later eruptions produced lava flows, cones and domes within and around these depressions.

Montagna Grande and Uplift

Montagna Grande forms the island’s highest area. The central block has been uplifted through volcanic and tectonic
processes, creating steep fault scarps and elevated terrain.

Favara Grande

Favara Grande is a fumarolic area where steam and volcanic gases emerge from the ground. Together with thermal
springs and warm soils, it demonstrates that heat and fluids continue to circulate beneath the island.

Lago di Venere

The coastal lake known as Lago di Venere, or the Mirror of Venus, occupies a volcanic depression. Hot springs and
gas emissions occur around parts of its shoreline.

Pantelleria Eruption History and Hazards

Pantelleria has produced both explosive eruptions and lava flows. Large prehistoric eruptions generated widespread
pumice and ash, while younger vents built cones and lava fields across the island.

An offshore submarine eruption was reported in the nineteenth century several kilometers northwest of Pantelleria.
Floating volcanic material and activity at sea illustrated that the active system extends beyond the island’s
coastline.

Potential Pantelleria Hazards

• Explosive eruptions and widespread ashfall
• Lava flows from newly opened vents
• Ballistic fragments near eruptive centers
• Pyroclastic density currents during larger explosive events
• Volcanic gas and fumarolic hazards
• Earthquakes and ground deformation
• Submarine eruptions and disruption to marine traffic

Although Pantelleria is much quieter than Etna or Stromboli, its geologically recent eruptions and continuing
geothermal activity justify scientific monitoring.

Italy’s Submarine Volcanoes

Some of Italy’s largest volcanic structures are almost completely hidden beneath the Mediterranean Sea. The
Tyrrhenian basin and Sicily Channel contain volcanic ridges, seamounts, calderas, hydrothermal vents and buried
eruptive deposits.

Submarine volcanoes are difficult to monitor because most of their edifices cannot be observed directly.
Scientists rely on seafloor mapping, ocean-bottom seismometers, water chemistry, remotely operated vehicles,
satellites and research vessels.

Learn more about underwater eruptions in our dedicated guide:

Submarine Volcanoes and Seamounts Explained
.

Marsili Seamount

Marsili is an enormous submarine volcano in the southern Tyrrhenian Sea, northwest of the
Aeolian Islands. It rises several kilometers above the surrounding seafloor but remains submerged.

Marsili is elongated rather than shaped like a simple symmetrical cone. Its structure reflects extension and
volcanic activity within the back-arc environment of the Tyrrhenian basin.

Geological and geophysical observations reveal volcanic rocks, hydrothermal alteration and evidence of
comparatively recent activity.

Could Marsili Generate a Tsunami?

Large submarine landslides, rapid flank collapse or powerful underwater explosions can generate waves. This has
led to public concern about Marsili.

However, the existence of a large submarine volcano does not mean that a catastrophic tsunami is imminent.
Scientists must evaluate slope stability, rock strength, faulting and evidence for past collapses rather than
assuming an entire edifice will suddenly fail.

Sensational claims should therefore be separated from evidence-based hazard assessment.

Palinuro Volcanic Complex

The Palinuro volcanic complex is a chain of submarine volcanic structures in the southern
Tyrrhenian Sea. It consists of multiple cones, ridges and hydrothermal areas rather than one isolated seamount.

Mineral deposits around hydrothermal vents record the circulation of hot, chemically reactive fluids through the
volcanic crust.

Palinuro provides evidence that magmatic and hydrothermal processes have occurred across a broad zone of the
seafloor northwest of Calabria.

Vavilov Seamount

Vavilov is another large volcanic edifice in the central Tyrrhenian Sea. It formed during the
tectonic extension and seafloor spreading that helped open the Tyrrhenian back-arc basin.

Vavilov is generally considered older than Marsili. Together, the two volcanoes document the migration of
extension and magmatic activity through the basin.

Much of the information about these submerged systems comes from bathymetric mapping, dredged rocks, seismic
profiles and magnetic measurements.

Campi Flegrei del Mar di Sicilia and Graham Island

The Campi Flegrei del Mar di Sicilia is a submarine volcanic field in the Sicily Channel. It
should not be confused with Campi Flegrei near Naples.

The field contains numerous submarine vents and banks. Its best-known eruption occurred in 1831, when activity
created a temporary island southwest of Sicily.

Ferdinandea or Graham Island

The temporary island was known by several names, including Ferdinandea, Graham Island and Île Julia. Different
countries attempted to claim it because of its strategic location.

Waves rapidly eroded the loose volcanic material, and the island disappeared below sea level within months.
Today, its summit remains as a shallow submarine bank.

The 1831 eruption illustrates how shallow submarine eruptions can create new land temporarily, ignite political
disputes and then vanish through erosion.

Empedocles Submarine Volcanic Complex

Detailed seafloor mapping has shown that Graham Bank belongs to a larger submarine volcanic structure commonly
called Empedocles.

The complex includes several volcanic centers and records repeated eruptions in the Sicily Channel. Most activity
remains hidden beneath the sea, emphasizing that Italy’s volcanic geography extends far beyond its visible islands
and mainland cones.

Hazards from Italian Submarine Volcanoes

How Italy Monitors Vesuvius, Campi Flegrei, Ischia, Vulcano and Pantelleria

The Istituto Nazionale di Geofisica e Vulcanologia is responsible for monitoring and scientific
surveillance of Italy’s active volcanic systems.

The Vesuvius Observatory monitors the Campanian volcanoes, including Vesuvius, Campi Flegrei and
Ischia. The Etna Observatory in Catania monitors Sicily, the Aeolian Islands and Pantelleria.

Seismic Networks

Permanent seismic stations detect earthquakes, volcanic tremor, explosions, rockfalls and fluid movement.
Scientists analyze event location, depth, magnitude and waveform.

GNSS and Ground Deformation

Satellite-navigation stations measure changes in the position of the ground with high precision. These networks
are essential for tracking uplift at Campi Flegrei and movement across other volcanic systems.

Satellite Radar Interferometry

Interferometric synthetic-aperture radar compares repeated satellite images to map ground deformation over broad
areas. It can reveal uplift, subsidence and fault movement that may be difficult to recognize at ground level.

Tiltmeters

Tiltmeters detect extremely small changes in ground slope. Rapid changes may accompany magma intrusion,
pressurization or movement of hydrothermal fluids.

Gas and Geochemical Networks

Instruments measure carbon dioxide, sulfur dioxide, hydrogen sulfide, radon and other gases. Scientists also
analyze fumaroles, springs, groundwater and soil emissions.

Gas ratios and isotopic compositions may help distinguish between shallow hydrothermal processes and deeper
magmatic input.

Thermal Monitoring

Infrared cameras, satellite sensors and direct measurements identify changes in fumarole temperature, hot ground
and thermal anomalies.

Gravity Measurements

Changes in gravity may reveal movement or redistribution of mass beneath a volcano, including magma or
hydrothermal fluids.

Marine Monitoring

Submerged parts of Campi Flegrei, Panarea and other volcanic systems require seafloor instruments, water sampling,
bathymetric surveys and remotely operated vehicles.

Drones and Visual Surveys

Drones allow scientists to inspect dangerous fumarolic fields, map fractures, measure temperatures and collect
imagery without placing observers directly in hazardous zones.

Italian Volcano Alert Levels and Civil Protection

Scientific monitoring and civil-protection decisions are related but distinct. INGV gathers and interprets
monitoring data, while civil-protection authorities evaluate operational measures and emergency actions.

Alert systems communicate the condition of a volcanic system using categories that may include colors and
descriptions of unrest. The exact procedures differ among volcanoes and emergency plans.

A higher alert level does not guarantee an eruption, while a low alert level does not mean that every volcanic or
earthquake hazard has disappeared.

During a crisis, readers should use:

• INGV bulletins and monitoring updates;
• the Italian Civil Protection Department;
• regional and municipal civil-protection authorities;
• official evacuation orders and access restrictions;
• authorized volcano guides where required.

Social-media videos, unofficial maps and isolated instrument graphs should never replace complete official
assessments.

How Italy’s Major Volcanoes Differ

Explore Related Volcano Guides

Italian Volcanic Hazards Explained

Italy’s volcanoes produce a wider range of hazards than lava alone. Explosive eruptions can generate
pyroclastic density currents, pumice fallout, ash clouds, ballistic rocks and volcanic lightning. Quieter
periods may still involve earthquakes, ground deformation, toxic gases, hydrothermal explosions, landslides
and dangerous changes in fumarolic areas.

The dominant hazard differs from one volcanic system to another. Mount Etna frequently threatens land and
infrastructure with lava flows and ashfall. Stromboli combines persistent summit explosions with the possibility
of sudden paroxysms, flank collapse and local tsunamis. Vesuvius and Campi Flegrei pose a greater risk from
explosive eruptions and pyroclastic density currents across densely inhabited terrain.

Volcano risk is determined not only by eruption size but also by population exposure, building vulnerability,
transport networks, evacuation time, weather conditions and public preparedness. A moderate eruption close to
an urban area may create a greater emergency than a much larger eruption in an isolated region.

Pyroclastic Density Currents

Pyroclastic density currents are among the deadliest volcanic phenomena associated with Italian
volcanoes. They are fast-moving mixtures of hot gas, ash, pumice and rock fragments that travel close to the
ground.

Some currents are dense and concentrated, while others are more dilute and turbulent. Both can move rapidly,
overwhelm buildings, ignite fires, bury landscapes and make survival extremely unlikely in directly affected
areas.

Pyroclastic currents can form when an eruption column collapses, when a lava dome or unstable crater deposit
fails, or when a laterally directed explosion propels material outward.

Italian Volcanoes Capable of Producing Pyroclastic Currents

• Vesuvius: Pyroclastic currents devastated Herculaneum and later reached Pompeii during the
  AD 79 eruption.
• Campi Flegrei: Past caldera-forming eruptions produced enormous ignimbrite sheets, while
  smaller future eruptions could generate localized or caldera-wide currents.
• Stromboli: Strong explosions and collapsing eruptive material can send pyroclastic currents
  down the Sciara del Fuoco and over the sea.
• Mount Etna: Pyroclastic currents are less common than lava flows but may occur during violent
  summit explosions or instability of eruptive deposits.
• Vulcano: Vulcanian or phreatomagmatic eruptions may generate pyroclastic surges and flows.
• Ischia and Pantelleria: Their geological records preserve deposits from explosive eruptions
  capable of producing pyroclastic currents.

Evacuation is the principal life-saving measure in areas threatened by major pyroclastic density currents.
Sheltering inside ordinary buildings cannot be assumed to provide adequate protection.

Volcanic Ashfall in Italy

Volcanic ash consists of fragments of rock, minerals and volcanic glass smaller than two millimeters. It is not
soft household ash and may have sharp, abrasive surfaces.

Fine ash can remain airborne for hours or days and travel hundreds of kilometers. Coarser lapilli and pumice
normally fall closer to a vent, but strong winds can carry them across large parts of Italy and the Mediterranean.

Effects of Volcanic Ash

• Reduced visibility on roads and at airports
• Flight delays, diversions and airport closures
• Breathing difficulties and eye irritation
• Damage to crops, vineyards and orchards
• Contamination of water-storage systems
• Abrasion of engines, turbines and machinery
• Electrical faults and short circuits
• Blocked drains and overloaded wastewater systems
• Roof collapse under thick or rain-soaked deposits

Eastern Sicily regularly experiences ashfall from Etna. Catania and surrounding towns may need to clear streets,
roofs, airport surfaces and public spaces after explosive summit activity.

A major Vesuvius or Campi Flegrei eruption could affect a much broader area. Wind direction would determine which
communities receive the greatest accumulation, meaning that ashfall zones cannot be treated as fixed circles
around a volcano.

Why Wet Ash Is Especially Dangerous

Ash becomes much heavier when saturated by rain. This additional weight can overload flat or weak roofs.
The danger is especially serious where buildings have not been maintained or were not designed to support heavy
volcanic deposits.

Rain can also wash ash into drains, sewers and river systems, increasing the likelihood of flooding and
sediment-laden flows.

Lava-Flow Hazards

Lava flows are the best-known hazard at Mount Etna, where fluid basaltic magma may erupt from summit craters or
fissures on the volcano’s flanks.

Most people can move away from a slowly advancing lava front, but the flow can still destroy homes, roads,
railways, power lines, farms, forests and water systems. The opening of a low-elevation vent may leave less time
to protect communities and infrastructure.

Lava may travel inside insulated tubes beneath a solid crust. These tubes reduce heat loss and allow molten rock
to move farther than an exposed surface flow.

Vesuvius, Ischia, Pantelleria, Vulcano and Stromboli have also produced lava flows. Their behavior depends on magma
composition, eruption rate, slope and vent position.

Can Lava Flows Be Diverted?

Attempts have been made to influence Etna lava flows using barriers, trenches, explosives and earthmoving
equipment. Such interventions may slow or redirect part of a flow under favorable conditions, but success is not
guaranteed.

Diverting lava can also transfer danger from one area to another. Decisions must therefore be made by authorities
using detailed topographic, legal and civil-protection assessments.

Volcanic Gases and Fumarolic Hazards

Italian volcanoes release water vapor, carbon dioxide, sulfur dioxide, hydrogen sulfide, hydrogen chloride and
other gases. Emissions may escape from summit craters, fumaroles, fractures, soil or underwater vents.

Gas concentrations can change as magma rises, pressure shifts or hydrothermal systems heat and fracture.
Scientists monitor both the amount of gas released and changes in chemical composition.

Carbon Dioxide

Carbon dioxide is colorless and odorless. Because it is denser than air, it may accumulate in depressions,
basements, caves, wells and poorly ventilated buildings.

High concentrations can displace oxygen and cause unconsciousness or death without obvious warning. Carbon
dioxide emissions are therefore carefully monitored in parts of Campi Flegrei, Vulcano and other geothermal
areas.

Sulfur Dioxide

Sulfur dioxide has a sharp odor and can irritate the eyes, throat and lungs. Large plumes may affect air quality
downwind and create acidic aerosols.

Hydrogen Sulfide

Hydrogen sulfide may smell like rotten eggs at low concentrations, but the sense of smell can become unreliable
at dangerous levels. Fumarolic areas should never be judged safe based solely on odor.

Volcanic Earthquakes and Ground Deformation

Earthquakes near Italian volcanoes may be caused by rising magma, movement of hydrothermal fluids, changing
underground pressure or slip on tectonic faults.

Different seismic signals reflect different processes. Brittle rock fracture produces volcano-tectonic
earthquakes, while sustained vibration known as volcanic tremor may be associated with moving magma or gas.

At Campi Flegrei, ground uplift stretches and fractures the shallow crust, producing earthquake swarms around
Pozzuoli and nearby areas. Even when no eruption follows, shallow earthquakes may damage vulnerable buildings.

Mount Etna also experiences tectonic and volcanic earthquakes. Magma intrusion can open fissures, while movement
of the volcano’s eastern flank interacts with major faults.

Ground deformation is measured with GNSS receivers, tiltmeters, leveling surveys and satellite radar. Inflation
may indicate increasing underground pressure, while deflation may follow magma withdrawal, gas release or changes
in hydrothermal systems.

No deformation pattern has one universal interpretation. Scientists compare ground movement with seismicity,
gas emissions, temperature and the known behavior of each volcano.

Phreatic and Hydrothermal Explosions

A phreatic eruption is a steam-driven explosion caused when groundwater is rapidly heated by
magma, hot rock or volcanic gas.

Water expands dramatically when it turns to steam. If the fluid is trapped beneath sealed or altered rock,
pressure may build until the surrounding material breaks apart.

Phreatic explosions can eject ash, mud, blocks and older volcanic rock without producing fresh lava. Because they
may originate in shallow hydrothermal systems, they can occur with shorter or less obvious warning than major
magmatic eruptions.

Solfatara, Pisciarelli, Vulcano and other Italian fumarolic areas contain hot, pressurized hydrothermal fluids.
Monitoring focuses on temperature, gas chemistry, seismicity and physical changes in vents and mud pools.

Volcanic Landslides and Flank Collapse

Volcanic edifices are constructed from layers of lava, ash, loose scoria and altered rock. Their steep slopes may
become unstable because of earthquakes, magma intrusion, erosion, heavy rainfall or long-term weakening by hot
acidic fluids.

A small rockfall may affect only the upper crater, while a major flank collapse can remove a large part of a
volcanic island or cone.

Stromboli and the Sciara del Fuoco

Stromboli’s Sciara del Fuoco channels eruptive debris toward the sea. Landslides on this unstable slope may
displace water and generate local tsunamis.

Ischia Landslides

Ischia’s steep slopes, fractured volcanic deposits and intense rain create serious landslide and debris-flow
hazards. These events can occur independently of a volcanic eruption.

Etna’s Moving Eastern Flank

Etna’s eastern flank slowly moves toward the Ionian Sea. This motion is monitored because it affects faults,
infrastructure and the long-term stability of the volcanic edifice.

Slow movement does not mean that catastrophic collapse is inevitable. Risk assessments must distinguish measured
deformation from exaggerated claims of an imminent mountain-wide failure.

Volcanic Tsunamis in Italy

Volcanic tsunamis can be generated when landslides, pyroclastic currents, explosions or caldera collapse rapidly
displace water.

Italy’s volcanic islands and submarine volcanoes make this an important coastal hazard, particularly in the
Aeolian Islands, the Bay of Naples, the Tyrrhenian Sea and the Sicily Channel.

Stromboli Tsunami Hazard

In December 2002, landslides from the Sciara del Fuoco entered the sea and generated waves that damaged buildings
and boats around Stromboli.

Local volcanic tsunamis may reach nearby shores within minutes. This leaves little time for distant official
warnings, making natural warning signs particularly important.

Natural Tsunami Warning Signs

• Strong or prolonged earthquake shaking
• A loud explosion or collapse from a coastal volcano
• Rapid, unusual withdrawal or rise of the sea
• A sudden roaring sound from the coast
• An official siren, message or evacuation order

Anyone observing these signs near a volcanic island should move inland and to higher ground without approaching
the shore to watch.

Explore this hazard in detail:
Volcanic Tsunamis Explained.

Volcanic Lightning

Lightning may develop inside ash-rich eruption columns when collisions among ash particles, ice and volcanic
fragments separate electrical charges.

Mount Etna and Stromboli have produced spectacular volcanic lightning during explosive episodes. The flashes may
appear close to the vent or higher within a rising ash plume.

Volcanic lightning is not evidence of unusual external energy. It is an atmospheric electrical phenomenon driven
by charge separation within turbulent volcanic material.

Learn more:
Volcanic Lightning Explained.

Historic Italian Volcanic Eruptions

Italy possesses one of the world’s longest records of human interaction with active volcanoes. Archaeology,
ancient literature, paintings, scientific observations and modern instruments document how eruptions repeatedly
altered settlements and landscapes.

Discover more major events in:
Historic Volcanic Eruptions Explained.

Italian Volcanoes and Archaeology

Volcanic disasters can destroy settlements, but rapid burial may also preserve buildings, roads, objects and
evidence of daily life.

Pompeii and Herculaneum are the most famous examples. Their streets, homes, wall paintings, shops and public
buildings provide an exceptional record of Roman society.

The eruption deposits themselves also preserve information. Layers of pumice, ash and pyroclastic material allow
volcanologists to reconstruct eruption sequences, wind direction, flow paths and the timing of building collapse.

Bronze Age sites buried by the Avellino eruption show that Vesuvius affected organized settlements long before
Roman times. Footprints, abandoned objects and animal remains offer evidence of evacuation and disrupted daily
life.

Archaeological sites inside Campi Flegrei reveal centuries of uplift and subsidence. Roman structures now located
below sea level record the long history of bradyseism around Pozzuoli and Baia.

Volcanoes in Italian Mythology and Culture

Italy’s volcanoes have influenced mythology, religion, literature, art and local identity for thousands of years.

Vulcan’s Forge

The Romans associated Vulcano Island with Vulcan, god of fire, metalworking and the forge. Smoke and glowing
eruptions were interpreted as signs of labor beneath the island.

Stromboli as a Mediterranean Beacon

Stromboli’s persistent nighttime glow made it a natural lighthouse for sailors crossing the Tyrrhenian Sea.

Etna and Ancient Myth

Greek and Roman traditions placed giants, monsters and divine workshops beneath Etna. The volcano’s earthquakes
and eruptions were interpreted as movements of beings imprisoned underground.

Vesuvius in Art and Literature

Vesuvius became a central image of the European Grand Tour. Paintings and written accounts presented eruptions as
both terrifying natural disasters and sublime spectacles.

Modern Italian communities maintain a more practical relationship with their volcanoes through agriculture,
tourism, civil-protection planning and repeated experience with ashfall or earthquakes.

Volcano Tourism in Italy

Italy offers some of the world’s most accessible volcanic landscapes. Visitors can see lava fields, summit
craters, fumaroles, calderas, hot springs, obsidian flows, archaeological sites and volcanic islands.

Accessibility does not eliminate danger. Conditions can change rapidly, and routes that are normally open may
become unsafe because of explosions, gas, snow, poor visibility, earthquakes or lava.

Essential Volcano-Tourism Safety Rules

• Check official conditions before departure.
• Use authorized guides where required.
• Respect barriers and exclusion zones.
• Do not approach active vents for photographs.
• Carry water, protective clothing and suitable footwear.
• Prepare for rapid weather changes at elevation.
• Never enter caves, depressions or closed areas where gas may accumulate.
• Leave immediately when guides or authorities instruct you to do so.

Volcanic Soils and Italian Agriculture

Weathered lava and ash can release potassium, phosphorus, iron, magnesium and other minerals. Over time, volcanic
soils may become highly productive when combined with sufficient water and careful land management.

Etna’s slopes support vineyards, citrus orchards, pistachios and other crops. Variations in elevation, lava age,
soil development and exposure create distinctive agricultural zones.

Vineyards also thrive around Vesuvius, Campi Flegrei, Ischia, the Aeolian Islands and Pantelleria. Volcanic soils,
sea influence and local grape varieties contribute to geographically distinctive wines.

Agriculture near active volcanoes involves a trade-off. Fertile land and tourism create economic opportunity, but
crops may be damaged by ash, lava, gas, earthquakes or evacuation.

Italian Volcanoes and Geothermal Energy

Heat from magma and hot rock warms underground fluids that may emerge as hot springs or remain trapped in
geothermal reservoirs.

Italy played a pioneering role in geothermal electricity production. The Larderello field in Tuscany became the
site of early experiments and commercial generation using natural steam.

Geothermal resources can provide relatively steady low-carbon energy, but development requires careful management
of fluids, induced seismicity, gas emissions and local environmental impacts.

Thermal waters also support spas and tourism on Ischia, Pantelleria, Vulcano and in several mainland volcanic
districts.

Italian Volcanoes and Aviation

Volcanic ash is hazardous to aircraft because particles can abrade windows, damage instruments and melt inside
jet engines.

Etna is especially important for aviation because it lies close to busy routes and Catania–Fontanarossa Airport.
Explosive summit activity may lead to airspace restrictions, runway cleaning, flight diversions or temporary
closure.

Ash advisories combine observations from INGV, meteorological data, satellite imagery, pilot reports and aviation
authorities.

The absence of heavy ashfall at ground level does not prove that an ash cloud is harmless to aircraft at altitude.

Can Italian Volcanoes Affect Climate?

A volcano can influence climate if a sufficiently large explosive eruption injects sulfur dioxide into the
stratosphere. The gas forms sulfate aerosols that reflect part of the incoming sunlight.

Most eruptions of Etna and Stromboli are too small or too low in the atmosphere to produce a major global climate
effect. They may still affect local air quality, weather observations and aviation.

Very large prehistoric eruptions from Campi Flegrei dispersed ash across Europe and the Mediterranean. Their
environmental effects remain an active area of research.

It is important to distinguish short-term volcanic cooling from long-term climate change. A large eruption may
temporarily reduce average surface temperatures, but volcanic aerosols settle out of the atmosphere and do not
cancel the long-term warming effect of accumulated greenhouse gases.

What Could the Next Major Italian Eruption Look Like?

No one can identify with certainty which Italian volcano will produce the next significant eruption. Etna and
Stromboli erupt most frequently, but a future crisis could also develop at Vesuvius, Campi Flegrei, Vulcano,
Ischia, Pantelleria or a submarine volcanic center.

Realistic planning considers multiple scenarios rather than predicting one exact event.

Scenario 1: An Etna Summit Eruption

A common scenario involves Strombolian explosions, lava fountains, ash plumes and lava confined mainly to the
summit region or Valle del Bove.

The largest effects could be ashfall, airport disruption, road closures and danger to visitors near the summit.

Scenario 2: A Low-Elevation Etna Flank Eruption

Fissures opening lower on the volcano could threaten towns, roads and utilities with lava flows. Earthquakes and
ground cracking might accompany magma intrusion.

Scenario 3: A Stromboli Paroxysm

A sudden powerful explosion could produce ballistic blocks, an eruption column, pyroclastic currents and fires.
Material entering the sea could generate local waves.

Scenario 4: Renewed Vesuvius Activity

Increasing earthquakes, deformation and gas changes might precede an eruption. Emergency decisions would focus
on evacuating the red zone before pyroclastic currents became possible.

The eruption could range from modest activity to a larger explosive event with widespread ashfall.

Scenario 5: A New Campi Flegrei Vent

A future eruption could open from a new location within the caldera rather than from Monte Nuovo or Solfatara.
Potential activity might include phreatic explosions, a small tuff cone or a more substantial explosive eruption.

Even without eruption, earthquake swarms and deformation could create a serious urban emergency.

Scenario 6: Vulcano Hydrothermal Crisis

Rising gas emissions and temperatures could lead to restrictions, evacuation of exposed zones or a steam-driven
explosion. A magmatic eruption would introduce additional ash, ballistic and pyroclastic hazards.

Scenario 7: A Shallow Submarine Eruption

Activity in the Sicily Channel or near an island could produce floating pumice, gas emissions, discolored water,
explosions and temporary new land.

Volcano Preparedness in Italy

Preparedness begins before a volcano becomes restless. Residents should understand whether their home, workplace
or school lies within an official volcanic, seismic, landslide or tsunami hazard zone.

Before Volcanic Unrest

• Learn the municipal civil-protection plan.
• Identify assembly areas and evacuation routes.
• Know how family members will communicate if networks fail.
• Prepare medication, documents, water, food and essential supplies.
• Keep protective masks and sealed eye protection available for ashfall.
• Plan assistance for children, older adults, pets and people with disabilities.
• Know how to shut off gas, electricity and water when instructed.
• Follow official sources before a crisis creates confusion.

During Volcanic Unrest

• Read complete official bulletins rather than isolated social-media posts.
• Expect earthquakes, road closures and changes in access rules.
• Keep vehicles fueled where authorities recommend doing so.
• Avoid fumaroles, craters, cliffs and unstable coastal slopes.
• Prepare to leave early when evacuation is announced.
• Do not enter restricted zones to retrieve possessions.

During Ashfall

• Stay indoors when possible.
• Close windows, doors and ventilation openings.
• Use a well-fitting particulate mask outdoors.
• Protect eyes with sealed glasses or goggles.
• Avoid driving unless necessary.
• Keep ash out of drains and wastewater systems.
• Remove roof ash only when it is safe and officially recommended.

During an Evacuation

• Leave when instructed rather than waiting for visible eruption signs.
• Follow assigned routes and destinations.
• Carry identification, medication and essential supplies.
• Do not take unofficial shortcuts through hazard zones.
• Check on vulnerable neighbors when safe to do so.
• Return only after authorities lift restrictions.

How to Recognize Volcano Misinformation

Italian volcanic unrest frequently attracts sensational headlines and viral social-media claims. Earthquake
swarms, gas emissions or ground uplift may be presented as proof that a catastrophic eruption is hours away.

Warning signs of unreliable coverage include:

• Claims of an exact eruption date without an official scientific basis
• Using the word “supervolcano” as a prediction rather than a geological description
• Presenting one earthquake or instrument graph without context
• Confusing ground uplift with guaranteed magma ascent
• Claiming that authorities are hiding an eruption while citing no monitoring data
• Using unrelated videos from another volcano or an earlier year
• Ignoring official bulletins that contradict the dramatic claim

Reliable updates should identify the responsible observatory, describe the monitoring evidence, acknowledge
uncertainty and distinguish current unrest from hypothetical worst-case scenarios.

Frequently Asked Questions About Italian Volcanoes