Vulsini, also known as Volsini volcano, Vulsini Volcanic District, Vulsini Volcanic Complex and the Vulsinian District, is a circular region of intrusive

igneous rock Igneous rock ( ), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava. The magma can be derived from partial ...

Lazio Lazio ( , ; ) or Latium ( , ; from Latium, the original Latin name, ) is one of the 20 Regions of Italy, administrative regions of Italy. Situated in the Central Italy, central peninsular section of the country, it has 5,714,882 inhabitants an ...

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

, about to the north northwest of

Rome Rome (Italian language, Italian and , ) is the capital city and most populated (municipality) of Italy. It is also the administrative centre of the Lazio Regions of Italy, region and of the Metropolitan City of Rome. A special named with 2, ...

, containing a cluster of

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the str ...

s known to have been active in recent geologic times. The Vulsinian region is one of dozens of intrusive circular regions, most smaller than the Vulsinian, arranged in a band from

Campania Campania is an administrative Regions of Italy, region of Italy located in Southern Italy; most of it is in the south-western portion of the Italian Peninsula (with the Tyrrhenian Sea to its west), but it also includes the small Phlegraean Islan ...

through

, called the Roman Comagmatic Province. A comagmatic province is a geologic area of the same type and age

deriving from the same crustal magma. The Roman region is post-collisional; that is, the intrusions were not a result of the lateral stresses that created Italy and raised the

Apennines The Apennines or Apennine Mountains ( ; or Ἀπέννινον ὄρος; or – a singular with plural meaning; )Latin ''Apenninus'' (Greek or ) has the form of an adjective, which would be segmented ''Apenn-inus'', often used with nouns s ...

, but were subsequent to Italy's creation. The Volsinian is the northernmost region. At relatively low altitude, the Vulsini calderas cover about and contain four

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

-age depressions known as Bolsena, Latera, Vepe and Montefiascone calderas. An alleged eruption occurred in 104 BC, but it is currently considered a misinterpretation of the description of a fire, and the most recent confirmed activity occurred in Pleistocene. The largest, the Bolsena caldera, which is roughly across, is filled with the waters of

Lake Bolsena Lake Bolsena () is a lake of volcano, volcanic origin in the northern part of the province of Viterbo called ''Alto Lazio'' ("Upper Latium") or ''Tuscia'' in central Italy. It is the largest volcanic lake in Europe. Roman historic records ind ...

, which derive mainly from deep

aquifers An aquifer is an underground layer of water-bearing material, consisting of permeability (Earth sciences), permeable or fractured rock, or of unconsolidated materials (gravel, sand, or silt). Aquifers vary greatly in their characteristics. The s ...

. Immediately to the northwest are the combined Latera and Vepe calderas, about by . Vepe, to the north of Lake Mezzano (a very small crater lake west of Lake Bolsena) is what is known as a nested caldera; it arose in the previously existing Latera Caldera. Italian routes SS74 and SS312 follow the rim from

Valentano 250px, View of Valentano. Valentano is a town and ''comune'' of the province of Viterbo, in the Lazio region of central Italy. It is from the provincial capital, Viterbo. left, 220px, Rocca Farnese in Valentano. The placename is of uncertain ori ...

through

Latera Latera is a small town and ''comune'' in the Province of Viterbo, Lazio, central Italy. Stephen Owen considers it to be an "archetypal" Italian hill town. Situated near Bolsena Lake and Mezzano Lake, is important for volcanic underground activi ...

westward, turning off before Mezzano on the other side. In addition the small Montefiascone caldera, also nested, lies between

Montefiascone Montefiascone is a town and ''comune'' of the province of Viterbo, in Lazio, central Italy. It stands on a hill on the southeast side of Lake Bolsena, about north of Rome. History The name of the city derives from that of the Falisci (''Mons Fa ...

on its eastern rim and the lake. Two islands in the lake, Bisentina and Martana, were formed from airfall

tuff Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock co ...

s in Pompeii-like eruptions. Dozens of other tuff cones dot the region, mainly on the eastern side of the complex. The Italian Civil Protection Department considers Vulsini as extinct.

Subfeatures

The following tuff cones stand out in the region: * Monte Becco * Isola Bisentina * La Dogana * Monte Evangelista, * Isola Martana * Molino *

* Monte Montione *

* Monte Pilato * Monte Rosso * Santa Luce * Santa Maria di Sala * Selva del Lamone * Monte Semonte * Monte Spinaio * Monte Bandinio

References

External links

*
Calderas of Italy Dormant volcanoes Pleistocene calderas Holocene calderas {{Lazio-geo-stub

Subfeatures

See also

References

External links