Vulcano island

Vulcano island is the closest eolian island to the sicilian mainland. It’s a deeply eroded cone with a deep crater at its center. Vulcano is the eponym of all volcanoes.

La Fossa cone on Vulcano island

La Fossa cone on Vulcano island

Vulcano island – historical eruptive centers

During the historical period, two eruptive centers: Fossa cone and Vulcanello have been the site of frequent and vigorous eruptions on Vulcano island.

Vulcanello

It forms the northernmost part of Vulcano island and consists of a lava platform on which three partly copenetrated volcanic cones grew up. They are aligned W-NW. Vulcanello formed as an independent islet in 183 b.C. Occasional eruptions from its three cones with both pyroclastic flow deposits and lavas occurred from then until 1550 a.D., with the last eruption creating a narrow isthmus connecting it to Vulcano island. Only in 1550 A.D., during its last eruption, it was joined to the main island by accumulation of pyroclastic deposits which formed the isthmus between the two docks of Levante and Ponente.

Vulcanello as seen from la Fossa crater rim (Vulcano island)

Vulcanello as seen from la Fossa crater rim

La Fossa

La Fossa active volcanic cone rises at the centre of la Fossa caldera, a sub-circular depression, located NW of the Piano Caldera. La  formed since 6000 years B.P. by the accumulation of pyroclastic deposits and minor lava flows.   Its most recent eruption occurred in 1888-1890.

Vulcano island – La Fossa last eruption

The most recent eruption at Vulcano island is the 1888-1890 eruption from the Gran Cratere  or Fossa di Vulcano, a large crater truncating the Fossa cone. Such eruption, one of the best observed eruption during XIX century (by G. Mercalli and O. Sivestri), started on August 3rd 1889 ending (with several breaks) on March 22sd 1890.  Volcanologists use the 1888-1890 vulcano island eruption as model of the “vulcanian eruptions”.

Vulcano island 1891 eruption  - original image (Silvestri- Mercalli) showing an explosion of the la Fossa crater

Vulcano island 1891 eruption – original image (Silvestri- Mercalli) showing an explosion of the la Fossa crater

 

Vulcano island crater

Vulcano island crater. In the foreground the steaming fumaroles with sulfur deposits inside. In the background it can see the ancient volcanic outcrops (B) of the cone “La Fossa” covered by the blackish ashes (A) of the last eruption of 1888-90

Vulcano island activity at nowdays

Recently, the Gran Cratere of the Fossa cone has been the site of volcanic unrest which began around 1985 and ended in 1995 without culminating in an eruption. Moreover, the most notably sign was an increase of the fumarolic activity. This episode has triggered increased public awareness about the volcanic risk at Vulcano and intense studies of the volcano. Geological studies have shown that most eruptions of the Fossa cone have been violently explosive and produced pyroclastic flows and surges. Future eruptions have to be expected to be of a similar character.

A volcanic bomb and fumarolic activity on Vulcano island crater rim

A huge volcanic bomb and fumarolic activity on Vulcano island crater rim

At nowdays a field of active fumaroles and extensive sulfur deposits lies in the northern-central portion of this crater. It provides a thrilling experience for those who dare to walk (or run) right across the gas plume emitted from the fumaroles. The vivid stench of sulfur dioxide within the plume is just the most evident indicator of toxic gases. It is advisable to stay as briefly as possible within the plume and better wear a gas mask. Prolonged stays in the plume may lead to undesirable effects, such as the (irreversible) loss of the sense of smell.

having different eruptive style compared with Stromboli volcano or Etna volcano.

Recomanded readings

J. Keller “The Island of Vulcano” (geological map included)