DESCRIPTION:
Italy Volcanoes and Volcanics

[Map,InlineGIF]
Major Volcanoes of Italy

This region ... is marked by traditions of record-keeping that go back thousands of years and by generations of historians devoted to mining those records. It is often called "The Cradle of Western Civilization", but it is also very much the cradle of volcanology. The earliest know documentation of volcanism is an Anatolian wall painting of a nearby cinder cone eruption around 6200 BC; the vigorous record of Etna goes back to 1500 BC; and the catastrophic eruption of Vesuvius in 79 AD, with the burial of Pompeii, continues to serve today as an object lesson in volcanism. The region has given us the first documented "new mountain", Monte Nuovo (Campi Flegrei), in 1538, the first "new island" at Santorini (Greece) in 197 BC, and the word "volcano" itself (derived from Vulcan, the Roman god of fire). ...

The volcanism of this broad region, stretching from Spain to the Caucasus, is largely the result of convergence between the Eurasian Plate and the northward-moving African Plate. The geology is diverse and complex, with microplates defying easy tectonic generalizations. However, subduction under the Greek islands (Hellenic arc) and southern Italy (Calabrian arc) explains the region's principal volcanic centers.

Select Major Volcanoes of Italy

• Campi Flegrei - Caldera - 458 meters high - ~13 kilometers diameter - Historical Eruptions
• Etna - Shield Volcano - 3,350 meters high - Historical Eruptions
• Stromboli - Stratovolcano - 926 meters high - Historical Eruptions
• Vesuvius - Complex Volcano - 1,281 meters high - Historical Eruptions
• Vulcano - Stratovolcano - 500 meters high - Historical Eruptions

Campi Flegrei (Phlegrean Fields) is a caldera approximately 12-14 kilometers across, located around 25 kilometers west of Vesuvius and 15 kilometers west-southwest of Naples. The caldera formed after a large eruption 35,000 years ago that produced 80 cubic kilometers of dense rock. Several other eruptions of decreasing intensity have occurred since then; its most recent eruption was in 1538. Since Roman times, Campi Flegrei has undergone vertical ground movements. During 1982-85, several ground upheaval and subsidence events were reported. ...

Since the ground upheaval events of 1982-84, systematic geochemical surveillance has been performed at Campi Flegrei. Fumarolic gases, crater lakes, and thermal springs have been monitored ...

The Phlegraean Fields (Campi Flegrei) is a volcanic area in southern Italy near the city of Naples; the town of Pozzuoli lies near the center of the Phlegraean Fields Caldera. Volcanic activity began in the late Pleistocene and has been localized at the edge of the Campanian Plain, which also includes Somma-Vesuvius and Roccamonfina. These volcanoes are located on the Tyrrhenian margin of the Apennine chain in a zone of intensely affected by extensional tectonism during the Quaternary (Armienti and others, 1983).

The volcanic field consists of multiple phreatic explosion craters and cinder cones within a 13-kilometer-diameter collapse caldera. The caldera formed about 35,000 years B.P. during or soon after the eruption of 80 cubic kilometers of Campanian tuff (Rosi and others, 1983). Much of the postcaldera volcanism occurred between 10,000 years B.P. and 8,000 years B.P., and between 4,700 years B.P., and 3,000 years B.P. (Rosi and others, 1983); different periods of post-caldera volcanism are inferred by Di Girolamo and others (1984). Postcaldera vents have migrated toward the center of the caldera and erupted volumes have decreased, suggesting progressive crystallization of a shallow magma reservoir (Armienti and others, 1983; Rosi and others, 1983). High temperatures (400 degrees C at 3-kilometer depth) and contact metamorphism of rocks penetrated by geothermal wells suggest that the top of the magma reservoir is now 4-5 kilometers deep. Early postcaldera volcanism was submarine; most subsequent volcanism has been subaerial. All periods of postcaldera volcanism have included frequent phreatic and phreatomagmatic explosions. ...

The caldera has a long history of uplift and subsidence as recorded in the geological record ... The caldera is also a classic locality of so-called bradyseisms (Greek for slow earthquakes, referring to decades to centuries of uplift and subsidence), as recorded in historical documents and by once submerged, then elevated, and now once again submerged Roman structures (Palatino, 1826; Babbage, 1847; Parascandola, 1947). The famous Serapeo marketplace in Pozzuoli has two generations of floors, the second built when the first one sank below sea level. ...

Slow uplift and subsidence are also known from other points in the Bay of Pozzuoli. Parascandola (1947) cites accounts of a pier at Nisida, built in the second century B.C., which was 6 meters lower in the early 18th century than when built. Roman ruins are also found below sea level along the northen and western shores of the Bay of Pozzuoli, near Monte Nuovo (Baia) and Miseno respectively (Palatino, 1826; Parascandola, 1947).

The Phlegraean Fields' long history of dramatic ground movements is unsurpassed anywhere in the world. Since Roman times, the elevation of the caldera floor has varied by more than 12 meters; in the 48 hours before the most recent eruption in 1538 (Monte Nuovo), the floor rose by at least 4-5 meters. ...

Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism. Historical lava flows cover much of the surface of this massive basaltic stratovolcano, Italy's highest and most voluminous volcano. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 kilometer horseshoe-shaped caldera open to the east. Two styles of eruptive activity typically occur at Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters, the Central Crater, NE Crater, and SE Crater (the latter formed in 1978). Flank vents, typically with higher effusion rates, produce eruptions from fissures that open progressively downward from near the summit (usually accompanied by strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank.

Spectacular incandescent nighttime explosions at Stromboli volcano have long attracted visitors to the "Lighthouse of the Mediterranean." Stromboli, the northeast-most of the Aeolian Islands, has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout historical time. The small, 926-meter-high island of Stromboli is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The active summit vents are located at the head of the Sciara del Fuoco, a horseshoe-shaped scarp formed as a result of slope failure that extends to below sea level and funnels pyroclastic ejecta and lava flows to the northwest. Essentially continuous mild strombolian explosions, sometimes accompanied by lava flows, have been recorded at Stromboli since Roman times.

The Somma-Vesuvius volcanic complex is a central composite volcano formed by and older stratovolcano (Monte Somma) with a summit caldera partially filled by the composite cone of Vesuvius. The most noted eruption, in 79 A.D., destroyed the ancient cities of Pompeii and Hurculaneum. Since the explosive sub-Plinian eruption of 1631, Vesuvius has erupted with both Strombolian and mixed effusive-explosive styles. For the past three centuries the volcanic activity has mainly focused inside the Somma caldera but occasionally lava issued outside it (i.e., 1760 eruption). The last cycle of activity ended with the 1944 eruption. Since then, the volcano has been characterized by moderate seismicity and intra-crater fumarolic activity.

On August 24, A.D.79, Vesuvius Volcano suddenly explosed and destroyed the Roman cities of Pompeii and Herculaneum. Although Vesuvius had shown stirrings of life when a succession of earthquakes in A.D.63 caused some damage, it had been literally quiet for hundreds of years and was considered "extinct". Its surface and crater were green and covered with vegetation, so the eruption was totally unexpected. Yet in a few hours, hot volcanic ash and dust buried the two cities so thoroughly that their ruins were not uncovered for nearly 1,700 years, when the discovery of an outer wall in 1748 started a period of modern archeology. Vesuvius has continued its activity intermittently ever since A.D.79 with numerous minor eruptions and several major eruptions occurring in 1631, 1794, 1872, 1906, and in 1944 in the midst of the Italian campaign of World War II. ...

In a "Vesuvian" eruption, as typified by the eruption of Mount Vesuvius in A.D.79, great quantities of ash-laden gas are violently discharged to form a cauliflower-shaped cloud high above the volcano.

The word "volcano" comes from the little island of Vulcano in the Mediterranean Sea off Sicily. Centuries ago, the people living in this area believed that Vulcano was the chimney of the forge of Vulcan -- the blacksmith of the Roman gods. They thought that the hot lava fragments and clouds of dust erupting form Vulcano came from Vulcan's forge as he beat out thunderbolts for Jupiter, king of the gods, and weapons for Mars, the god of war. In Polynesia the people attributed eruptive activity to the beautiful but wrathful Pele, Goddess of Volcanoes, whenever she was angry or spiteful. Today we know that volcanic eruptions are not super-natural but can be studied and interpreted by scientists.

Vulcano is located at the southern boundary of the Aeolian Islands, about 25 kilometers 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.

Return to:
[Italy Volcanoes and Volcanics Menu] ...