Vesuvius

The volcano

Mt. Vesuvius is the best known volcano on earth; it dominates the Bay of Naples with its characteristic cone. It is a typical example of a volcano in a volcano made by an outer broken cone, Mt. Somma (1133 metres) with a crateric belt most of which is destroyed. In it there is a smaller cone, the Mt. Vesuvius (1281 metres), divided by lowering named Valle del Gigante (Giants Valley), a part of the ancient caldron where in a later period, perhaps during the 79 A.D. eruption, the Gran Cono (Great Cone) or Mt. Vesuvius arose. The Valle del Gigante is still divided in Atrio del Cavallo on the west and the Valle dell'Inferno on the east. The Somma's ancient crater is well preserved as far as its entire northern part is concerned, in fact in historic times it was less exposed to the volcano's devastating violence, because it was well protected by the height of the internal face that has prevented the downflow of lava on its slopes. The slopes, which vary in their steepness, are furrowed by profound radial grooves produced by the erosion of the meteoric waters. The whole section is then characterized by dikes and fringes of dark volcanic rock. The old crater edge is a stream of summits called cognoli . While the height of mount Somma and its profile have remained the same for centuries, the height and the profile of the mount Vesuvius have suffered considerable variation, because of the following eruptions, with raisings and lowerings. Mt. Vesuvius is a characteristic polygenic mixed volcano, meaning that it is constituted by lava of different chemical composition (for example trachytes, tephrites, leucitites) and formed either by casting of lava or pyroclastic deposits. All the zones at the slopes of the mountain are formed by transported earth of lava mud which goes down from the steep slopes in the rainy seasons through deep and narrow grooves called channels or more commonly "lagni". The high embankments are formed by piles of lavic scoriae, which precipitated in incandescent state and spread towards the low slopes, proving precious for the vegetation thanks to their fertile material, rich in silicon and potassium. Proceeding along the rim of the crater, one can observe the whole extent of the southern part of the volcano and, during days with good visibility, it is possible to see the entire gulf of Naples, from the Sorrento peninsula to Cape Miseno, Procida and Ischia. It is also possible to note the large number of buildings which have been built on the vulnerable flanks of the mountain.

 

 

 

 

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The activity between 79 AD and 1631

The most famous and destructive eruption of Mt. Vesuvius occurred in AD 79. Greek and roman scholars (Strabo, Diodorus Siculus, Vitruvius, Vergil) already knew the volcanic nature of the mountain before this eruption. It destroyed many towns around Vesuvius. A detailed description was made by Pliny the Younger who observed the eruption from Cape Misenum at a distance of about 20 km from the volcano. During the eruption the uncle of Pliny the Younger (Pliny the Elder), admiral of the roman fleet based in Misenum, went to the rescue of the people endangered by the eruption and lost his life. We have no information on the state of Vesuvius immediately after the eruption of 79. The first account of continuing activity is from Galenus (c.172 AD) who testifies that "the matter in it (Vesuvius) is still burning" . Dio Cassius in 203 AD reports a violent eruption heard in Capua, some 40 km from the volcano. Two large eruptions occurred in 472 and 512. Marcellinus Comes reported that, on the 6th of November, 472, "Vesuvius (...) erupted the burning interiors, caused night during the day and covered all Europe with fine ash" . Information about the eruption of 512 is more detailed. Cassiodorus, an officer of king Teodoricus, wrote a letter to ask the exemption of taxes for the people affected by the eruption; in his letter he reports that "a burnt ash flies in the sky, and, forming ashy clouds, it rains with ash droplets also in the provinces beyond the sea (...). It is possible to see ash rivers flowing like liquid, bringing hot sands and (....) the fields grow suddenly up (the fields are covered with sand) to the top of the trees (.....) and are ravished by the sudden heat" . Several other eruptions are reported in 685 (Paulus Diaconus), 787 and 968. In 968, Leo Marsicanus reports in a chronicle of the Cassino Monastery that "Mount Vesuvius exploded with flames and emitted a great amount of gluey and sulphurous matter that formed a river hurriedly flowing to the sea" . Several authors report other eruptions in 991, 993 and 999 (see in Alfano, 1924) but they must be regarded as suspicious because of the belief of the end of the world in 1000 AD. Leo Marsicanus refers of another eruption on the 27 of January, 1037, that lasted for six days. The chronicle of the Cassino monastery records an explosive eruption between 1068 and 1078. The last eruption before a long quiescent period occurred on the 1st of June, 1139. Several sources refer to it as a strong explosive eruption (Falcone Beneventano, the Chronicle of the Monastery of Cava dei Tirreni, John of Salisbury). It lasted eight days and ashes covered Salerno, Benevento, Capua and Naples. No reliable report of volcanic activity is available until 1500, when Ambrogio di Nola reports a small explosion. From 1500 until to 1631, no eruption occurred on Vesuvius. Records are good during this period, and none mention volcanic activity.

 

The activity between 1631 and 1944

The great eruption of 1631 is the largest explosive eruption of Mt. Vesuvius since those of 472 and 512 AD. It occurred after 131 years of quiescence. Large trees covered the Gran Cono, the cone within the Somma Caldera, and local people did not remember it being a volcano. The mountain was called "La Montagna di Somma" (the Mountain of Somma, a small town on its northern side). Several months before the beginning of the eruption, people near the volcano felt some earthquakes (Braccini, 1632). They were not particularly scared because earthquakes from the nearby Apennine chain were often felt in the area (a large one had occurred three years before in Apulia, in 1628). The seismic activity became more severe in the few days before the eruption. Nevertheless, the awakening of Vesuvius in 1631 surprised the inhabitants. A strong explosive eruption started in the night between 15 and 16 December of 1631 and its paroxysmal stage lasted two days. Between the great eruption of 1631 and 1944 Vesuvius, is almost always in activity with only brief periods of quiescence not exceeding 7 years. Major eruptions occurred in 1794, 1822, 1834, 1850 e 1872. After 1872 slow lava effusions, lasting several years formed small lava accumulation (lava domes) in the proximity of the crater. One of this, named Colle Umberto, formed between1895 and 1899 in the area between the cone and the Observatory. In 1872, after the eruption, Vesuvius cone had its maximum elevation at 1335 m a.s.l.. In May, 1905, a new eruption began, firstly with slow lava effusions and, since January, 1906, with intermittent explosive activity (strombolian activity). On the 7th of April, 1906 the eruption reached the climax with lava fountains and earthquakes. The eruptive column of ash and gas reached the height of 13000 m. The eruption ends in the last days of April. During the eruption of 1906 the top of Vesuvius was truncated and formed a vast crater with a diameter of approximately 500 m and a depth of 250 m. The crater rim was lowered to 1145 m asl at its minimum height. After the eruption there was short period of quiescence followed by a prolonged period of permanent activity since 5 July of 1913. This activity , caracterized by quiet effusion of lava and minor explosion from a small conelet, slowly filled the 80 million m3 crater left by the eruption of 1906. By 28 November of 1926 the crater had been filled up to its lower edge (~1070 m) and from that time on, small lava flows descended along the slopes of the crater. In June 1929 a major lava flow extended outside the Somma caldera rim and reached the village of Terzigno on the eastern slope of the volcano. The lava flow emission was followed by a phase of lava fountaining accompanied by sustained seismic tremor. By 1944 the lava field had almost filled up all the extension of the crater up to the altitude of about 1140-1150 m asl. Only a few remains of the original crater were visible especially on the south-western rim , where was located the highest point of the crater at 1186 m asl. The conelet, built at the center the lava field, had reached an height of ~1260 m asl. On 6 January, 1944 there was an lava flow from the conelet that rapidly reaches the border of the rim and outflows. The small lava flows continues until 26 January outside the rim and until 23 February within it. On that day the activity ends. The eruption of Mt. Vesuvius of March 1944, is the last eruption occurred at Vesuvius. Since then the volcano has been in a quiescent stage without any major sign of activity.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The park

The Vesuvius National Park was founded on the 5 of June, 1995. It was founded in order to preserve animal and vegetable species, vegetable and forest associations, geological peculiarities, palaeontological formations, biological communities, biotopes, scenic and panoramic values, natural processes, ecological balances. Its purposes are, moreover, the application of ways of management or environmental restoration suitable to realize an integration between man and the natural habitat, also through the protection anthropological, archaeological, historical and architectural values and the protection of traditional and pastoral activities; the promotion of educational and formative activities of scientifis research, that can be interdisciplinary too, the promotion of compatible recreational activities as well; another purpose is the defence and the reconstitution of hydraulic and hydrogeological balances. The task and the values concerning the Vesuvius National Park are even wider because we have to defend the most famous volcano in the world, and at the same time one of the five most dangerous volcanoes in the world because of the high urban conurbation that ahs recently grown up around it, disrespectful of the laws forbidding the construction of buildings. So the Vesuvius National Park represents an anomaly among the European National Parks, a sort of challenge aimed to rescue the wild and enchanting beauty of Vesuvius and Monte Somma (Somma Mountain), pulling them away from the incredible deterioration and giving them back to the pleasure of the old and the new generations they belong to.

Environment and Nature

The territories around the Vesuvius and Monte Somma are differentfor various environmental seasons but, at the same time, they share some aspects, in particular the strong anthropization that characterizes the lowest slopes of both mountains. Speaking of the differences, it is necessary to point out that the first area is drier and sunnier than the other, with a typical Mediterranean vegetation, artificial grown pinewoods and ilex trees, which are occupying more ground in comparison with pines, and are reforming the splendid Mediterranean forest. The second (Monte Somma) is damper with a wood vegetation similar to the Apennine one, with chestnut woods, oak trees, alders, maples, ilexes; among these there is, even if rarely found, the wonderful birch, a very unusual presence in a Mediterranean habitat. The colonization of lava grounds by the numerous plants, begins after the cool down and is due to the liche Stereocaulon vesuvianum , which has a coral shape, it is grey and is the first living being which installed itself on the cold lava by preparing the land in receiving roots of the plants. It entirely covers the Vesuvian lava making it change to grey, giving the lava a silvery reflection during the full-moon nights. The list of plants includes 906 different species. Among these species we can observe interesting types, such as the Neapolitan maple, the Neapolitan alder and the Helichrysum litoreum , particularly abundant on the Vesuvius. We can point out also the large number of orchids (23) and the broom present in different species: Genista tinctoria, Genista aetnensis ; the last one was imported from Etna in 1906 and today it is widespread on the entire Vesuvian territory.

The fauna

The fauna of the Park is particularly rich and interesting. Among mammals, there is the "oaken mouse", the presence of whiwh is rare in other parts of Italy, but there is also a presence of the dormouse, the beech-marten, the fox, the wild rabbit, and of the hare. More than 100 species of birds live there, which can be classified as resisents, migrants, wintering and breeding. Interesting is the contruction of nests by the various birds, the buzzars, kestrel, hoopoe, turtle-dove, woodpidgeon, great spotter woodpecker, rock thrush, raven, coal tit. Recently there have been more frequent observations of the sparrowhawk, a very elegant and woody predatory bird. During the winter the woodcock, the black redstart, the wryneck, the song thrush, the siskin remain in the Park. During the period of mogrations garden warblers, subalpine warblers, pied flycatchers, redstarts, black eared wheater, woodwarblers, golden orioles, nightjars, bee eaters and many other species fly over the Park, many of which coming from sub-saharian quarters where they spend the winter. Among the reptiles we have to mention the coloured green-lizard, the inoffensive western whyp snake and the Turkish Gecko. Among the invertebrates we can notice the most coloured diurnal and nocturnal butterflies that remain during the flowering of the Mediterranean Vesuvian soil.

Agriculture and Craftmanship

The Vesuvian agriculture, thanks to the lava ground rich in minerals, to the excellent draining and to the Mediterranean climate, is considered unique for the variety and the special taste of its products. Among the various fruits, apricots and cherries are the typical products of the area. Of the hundreds of different kinds of existent apricots, the most widely known are the "Pellecchiella", that are considered the best for their particularly sweet taste and for the compactness of the pulp, the "Boccuccia liscia" with a bittersweet taste and the "Boccuccia spinosa", called in that way for the skin which is not smooth, the "Cafona", the "Carpone" with a sugary taste. Of the other kinds, all very tasty, we must remember "Baracca", "Vitillo", "Monaco bello", "Prete", "Palummella". The cherries, less numerous, are cultivated mostly at the foot of Monte Somma. Among the most famous we must remember the "Ciliegia Malizia", with a red consistent and juicy pulp and aromatic taste and the "Ciliegia del Monte", that is considered the best for eating: its colours are yellow and red, and the pulp is light, juicy and scented. Other typical products are the famous "Pomodorini da serbo" (small tomatoes). They are small, round, with a characteristic pointed end, and they have a sweet acidulous taste, due to the special concentration of sugars and moneral salts. They are picked unripen in summer and preserved tied to a string twisted in a circle. Kept in dry places and far from sunlight, they ripen, preserving their tasty and succulent pulp, protected by the skin, that slowly dries up. The bunch of "Pomodorini" picked in this way, are called "piennolo", They are used on macaroni, on pizza, and make very good sauces for fish and for meat. The volcanic complex of Somma-Vesuvio is moreover famous (since the time of the ancient Romans) for the greatness of its wines. At the foot of the volcano the grapes "Falanghina" of Vesuvius, the "Coda di volpe" (locally called "Caprettone") are cultivated and the "Piedirosso" of Vesuvius from which we can obtain the famous "Lachryma Christi", a wine with an enjoyable vinous scent with a dry and aromatic taste. We find a variety of red, rose and white wine and it becomes DOC when it reaches 12 percent alcohol. Let us not forget the "Catalanesca" grapes, very good for their plump and sweet pulp, that grow in small quantities mostly at the slopes of Monte Somma. A particular wine is obtained from the local farms characterised by its opaque colour and its strong after-taste. Among the vegetables we can point out, in addiction to the fennels and beans, also "Friarielli", which is broccoli that has a strong and bitter taste used in Italian cooking to flavour macaroni, meat and pizza. Speaking of the dried fruits, walnuts and nuts are excellent. The production of honey is also very widespread. The Vesuvian handcrafts have old origins. They show signs of of a glorious activity close to art andsometimes blended together with it, giving a strong impulse to authentic artistic handcrafts. The Vesuvian handcraft known and appreciated for its quality of work and its use of materials, characterized by the presence of such a disruptive neighbour, is the result of tenacious work: corals and cameos, limestone, copper and various materials are mounted and cut, engraved, forged by able hands, guided by a true passion. Thanks to the renewal and efficient use of historical places (Ville Vesuviane), today the artisan production is overcoming the old mistrust for co-operative working and is promoting its products at the highest international levels.