Phlegraean Fields

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Phlegraean Fields
Campi Flegrei
Pozzuoli NASA ISS004-E-5376 modified names.jpg
A NASA space shuttle's photo of the area, with main features labeled
Highest point
Elevation 458 m (1,503 ft) [1]
Coordinates 40°49′37″N 14°08′20″E / 40.827°N 14.139°E / 40.827; 14.139Coordinates: 40°49′37″N 14°08′20″E / 40.827°N 14.139°E / 40.827; 14.139[1]
Geography
Location Italy
Geology
Age of rock 40,000 years
Mountain type Caldera[1]
Volcanic arc/belt Campanian volcanic arc
Last eruption September to October 1538[1]
Sulfur at the Solfatara crater
Relief Map

The Phlegraean Fields (Italian: Campi Flegrei [ˈkampi fleˈɡrɛi]; from Greek phlego φλέγω, "to burn")[2][citation needed] are a large volcanic area situated to the west of Naples, Italy. It was declared a regional park in 2003. Lying mostly underwater, the area of the caldera comprises 24 craters and volcanic edifices. Hydrothermal activity can be observed at Lucrino, Agnano and the town of Pozzuoli. There are also effusive gaseous manifestations in the Solfatara crater, the mythological home of the Roman god of fire, Vulcan. This area is monitored by the Vesuvius Observatory.[3]

The area also features bradyseismic phenomena, which are most evident at the Macellum of Pozzuoli (misidentified as a temple of Serapis), as geologists puzzled over bands of boreholes left by marine molluscs on marble columns, showing that the level of the site in relation to sea level had varied.

Geological phases[edit]

Three geological phases or periods are recognised and distinguished.[4]

  • The First Phlegraean Period. It is thought that the eruption of the Archiflegreo volcano occurred about 39,280 ± 110 years (older estimate ~37,000 years) ago, erupting about 200 km3 (48 cu mi) of magma (500 km3 (120 cu mi) bulk volume)[5] to produce the Campanian Ignimbrite eruption.[6] Its Volcanic Explosivity Index (VEI) was 7. "The dating of the Campanian Ignimbrite Eruption (CI) to ~37,000 calendar years B.P. draws attention to the coincidence of this volcanic catastrophe and the suite of coeval, Late Pleistocene biocultural changes that occurred within and outside the Mediterranean region. These included the Middle to Upper Paleolithic cultural transition and the replacement of Neanderthal populations by anatomically modern Homo sapiens, a subject of sustained debate.[7] No less than 150 km3 of magma were extruded in this eruption (the CI eruption), whose signal can be detected in Greenland ice cores. As widespread discontinuities in archaeological sequences are observed at or after this eruption, a significant interference with ongoing human processes in Mediterranean Europe is hypothesized." [8] New research led by Liubov Vitalievna Golovanova and Vladimir Borisovich Doronichev of the ANO Laboratory of Prehistory in St. Petersburg, Russia, supports the hypothesis that these eruptions drove Neanderthals to extinction and cleared the way for modern humans to thrive in Europe and Asia.[9] The area is characterised by banks of piperno (it) and pipernoid grey tuff at Camaldoli hill, like in the northern and western ridge of Mount Cumae; other referable deep products are those found at Monte di Procida, recognizable in the cliffs of its coast.
  • The Second Phlegraean Period. Between 35,000-10,500 years ago,[4] it is characterized by the yellow tuff that is the remains of an immense underwater volcano, with a diameter of c. 15 kilometres (9.3 mi); Pozzuoli is at its center. Approximately 12,000 years ago the last major eruption occurred, forming a smaller caldera inside the main caldera, centered on the town of Pozzuoli. This event produced the Neapolitan yellow tuff, referring to the characteristic yellow rocks there.
  • The Third Phlegraean Period. Dated between 8,000 – 500 years ago,[4] it is characterized by white pozzolana, the material that forms the majority of volcanos in the Fields. Broadly speaking, it can be said there was an initial activity to the south-west in the zone of Bacoli and Baiae (10,000-8,000 years ago); an intermediate activity in an area centred between Pozzuoli, Spaccata Mountain and Agnano (8,000-3,900 years ago); and a more recent activity, moved towards the west to form Lake Avernus and Monte Nuovo (New Mountain) (3,800–500 years ago).
  • There are volcanic deposit indicating possible eruption, dated by argon at  315,000, 205,000, 157,000 and 18,000  years ago.[citation needed]

More recent history[edit]

A fumarole at the Phlegraean Fields; painting by Michael Wutky (1780s)

The caldera, which now is essentially at ground level, is accessible on foot. It contains many fumaroles, from which steam can be seen issuing, and over 150 pools of boiling mud at last count. Several subsidiary cones and tuff craters lie within the caldera. One of these craters is filled by Lake Avernus.

In 1538, an eight-day eruption in the area deposited enough material to create a new hill, Monte Nuovo. It has risen about 2 metres (7 ft) from ground level since 1970. It is a volcano capable of producing VEI 7 eruptions, as large as that of Tambora in 1815.[10]

At present, the Phlegraean Fields area comprises the Naples districts of Agnano and Fuorigrotta, the area of Pozzuoli, Bacoli, Monte di Procida, Quarto, the Phlegrean Islands (Ischia, Procida and Vivara).[citation needed]

A 2009 journal article stated that inflation of the caldera centre in the vicinity of Pozzuoli might presage an eruptive event within decades.[11] In 2012 the International Continental Scientific Drilling Program planned to drill 3.5 km (2.2 miles) below the earth's surface near Pompeii intending to monitor the massive molten rock chamber below in order to provide early warning of any eruption. Local scientists are worried that such drilling itself could initiate an eruption or earthquake. In 2010 the Naples city council had prevented the drilling project. Programme scientists said the drilling was no different from industrial drilling in the area. The newly elected mayor allowed the project to go forward. A Reuters article emphasized that the area could produce a "super volcano" that might kill millions.[12]

Most recent study from Istituto Nazionale di Geofisica e Vulcanologia describing recent volcanic unrest of Campi Flegrei caldera from January 2012 to June 2013 characterised by rapid ground uplift of about 11 centimetres (4 in) with a peak rate of about 3 centimetres (1 in) per month during December 2012 mentions, that in previous years from 1985 to 2011 dynamics of ground uplift has been mostly linked to caldera's hydrothermal system. As study describes, this relation broke down in 2012 and the driving mechanism of the ground uplift changed to periodical emplacement of a magma within a flat, sill-shaped magmatic reservoir in depth cca 3,000 metres (9,843 ft), 500 metres (1,640 ft) south from port of Pozzuoli[13]

Wine[edit]

Italian wine, both red and white, under the Campi Flegrei DOC appellation comes from this area. Grapes destined for DOC production must be harvested up to a maximum yield of 12 tonnes/hectare for red grape varieties, and 13 tonnes/ha for white grape varieties. The finished wines need to be fermented to a minimum alcohol level of 11.5% for reds and 10.5% for whites. While most Campi Flegrei wines are blends, varietal wines can be made from individual varieties, provided the variety used comprises at least 90% of the blend and the wine is fermented to at least 12% alcohol for reds and 11% for whites.[14]

Red Campi Flegrei is a blend of 50-70% Piedirosso, 10-30% Aglianico and/or Sciascinoso and up to 10% of other local (both red and white) grape varieties. The whites are composed of 50-70% Falanghina, 10-30% Biancolella and/or Coda di Volpe, with up to 30% of other local white grape varieties.[14]

Cultural importance[edit]

Campi Flegrei has had strategic and cultural importance.

See also[edit]

Sources[edit]

References[edit]

  1. ^ a b c d "Campi Flegrei". Global Volcanism Program. Smithsonian Institution. Retrieved 2008-09-20. 
  2. ^ "flegreo". Garzantilinguistica. Retrieved September 20, 2016. 
  3. ^ http://www.ov.ingv.it/OV/en/campi-flegrei.html
  4. ^ a b c Brand, Helen. "Volcanism and the Mantle: Campi Flegrei" (PDF). Retrieved 2008-06-18. 
  5. ^ Fisher, Richard V.; Giovanni Orsi; Michael Ort; Grant Heiken (June 1993). "Mobility of a large-volume pyroclastic flow — emplacement of the Campanian ignimbrite, Italy". Journal of Volcanology and Geothermal Research. Elsevier. 56 (3): 205–220. Bibcode:1993JVGR...56..205F. doi:10.1016/0377-0273(93)90017-L. Retrieved 2008-09-20. 
  6. ^ Fedele, Francesco G.; et al. (2002). "Ecosystem Impact of the Campanian Ignimbrite Eruption in Late Pleistocene Europe". Quaternary Research. 57 (3): 420–424. Bibcode:2002QuRes..57..420F. doi:10.1006/qres.2002.2331. Retrieved Oct 8, 2010. Abstract 
  7. ^ Neanderthal Apocalypse Documentary film, ZDF Enterprises, 2015. Retrieved 26 January 2016.
  8. ^ De Vivo, B.; G. Rolandi; P. B. Gans; A. Calvert; W. A. Bohrson; F. J. Spera; H. E. Belkin (November 2001). "New constraints on the pyroclastic eruptive history of the Campanian volcanic Plain (Italy)". Mineralogy and Petrology. Springer Wien. 73 (1-3): 47–65. Bibcode:2001MinPe..73...47D. doi:10.1007/s007100170010. Retrieved 2008-09-20. 
  9. ^ "Volcanoes Wiped out Neanderthals, New Study Suggests". ScienceDaily. Oct 7, 2010. Retrieved Oct 10, 2010. The research is reported in the October issue of Current Anthropology 
  10. ^ Newhall, Christopher G.; Self, Steve (1982). "The volcanic explosivity index (VEI): An estimate of explosive magnitude for historical volcanism". Journal of Geophysical Research. 87 (C2): 1231–1238. Bibcode:1982JGR....87.1231N. doi:10.1029/JC087iC02p01231. 
  11. ^ Isaia, Roberto; Paola Marianelli; Alessandro Sbrana (2009). "Caldera unrest prior to intense volcanism in Campi Flegrei (Italy) at 4.0 ka B.P.: Implications for caldera dynamics and future eruptive scenarios". Geophysical Research Letters. 36 (L21303): L21303. Bibcode:2009GeoRL..3621303I. doi:10.1029/2009GL040513. 
  12. ^ Antonio Denti, "Super volcano", global danger, lurks near Pompeii, Reuters, August 3, 2012.
  13. ^ D’Auria, Luca; Susi Pepe; Raffaele Castaldo; Flora Giudicepietro; Giovanni Macedonio; Patrizia Ricciolino; Pietro Tizzani; Francesco Casu; Riccardo Lanari; Mariarosaria Manzo; Marcello Martini; Eugenio Sansosti; Ivana Zinno (2015). "Magma injection beneath the urban area of Naples: a new mechanism for the 2012–2013 volcanic unrest at Campi Flegrei caldera". Scientific Reports. Nature Publishing Group. 5: 13100. doi:10.1038/srep13100. 
  14. ^ a b P. Saunders Wine Label Language pg 132 Firefly Books 2004 ISBN 1-55297-720-X
  15. ^ "Pozzuoli: history, archeology, art, architecture, environment". 
  16. ^ Liubov Vitaliena Golovanova; Vladimir Borisovich Doronichev; Naomi Elancia Cleghorn; Marianna Alekseevna Koulkova; Tatiana Valentinovna Sapelko; M. Steven Shackley (October 2010). "Volcanoes Wiped out Neanderthals, New Study Suggests" (news release). ScienceDaily. University of Chicago Press Journals. Journal Current Anthropology. 51 (5): 655–691. doi:10.1086/656185. Significance of Ecological Factors in the Middle to Upper Paleolithic Transition 

External links[edit]