Pico do Fogo
| Pico do Fogo | ||
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 Pico do Fogo with Pico Pequeno (right) |
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| height | 2829 m | |
| location | Fogo , Cape Verde | |
| Coordinates | 14 ° 57 '2 " N , 24 ° 20' 32" W | |
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| Type | Stratovolcano | |
| Last eruption | 2014 | |
| Normal way | Portela - Pico do Fogo | |
The Pico do Fogo ( top or summit of the fire, or fire top or fire summit ) on the island of Fogo is the highest point of the Cape Verde Islands with a height of 2829 m and after the Teide , on Tenerife , the second highest in Macaronesia .
geography
The Pico do Fogo is a layer of volcanic cone that rises 1200 m above the east side of the Chã das Caldeiras . The Chã das Caldeiras is a semicircular rock basin at an altitude between 1600 m and 1700 m above sea level and with a diameter of about 9 km. The Chã das Caldeiras is not a classic collapse crater , but was created by an enormous landslide , after which the Pico do Fogo built up on the east side. In the south and west, the Chã das Caldeiras is dominated by almost vertical, 1000 m high rock walls, the Bordeira de Fogo .
A huge eruption from the main crater of Pico in 1680 gave the island, then called "São Filipe", the name Fogo (English: " Fire "), which has been retained until today . Further eruptions followed in 1785, 1799, 1847, 1852, 1857 and 1951.
During the eruption on April 2, 1995, the lava flow of which was limited to the interior of the Chã das Caldeiras, a small secondary volcano (Pico Pequeno 1950 m ) formed at the western foot of the Pico. After the eruption of Pico Pequeno, large parts of the cultural landscape in the Caldeira were destroyed and the 2,000 inhabitants were temporarily evacuated.
On the morning of November 23, 2014 there was another eruption with ash and lava ejecting at the same point as the 1995 eruption. The ongoing eruption destroyed the southern and central part of Portela and about 70% of the neighboring ones until December 7, 2014 Bangaeira parish . The eruption increased in intensity and covered the hamlet of Portela for the most part with a lava flow that destroyed all of the residents' belongings . On February 8, 2015, the volcano stopped its eruptive activity after 77 days.
The living conditions are still simple, there is no public water or electricity supply. Burgeoning tourism and small-scale viticulture are the main sources of income. The Pico is part of a nature reserve. For the demanding but not particularly difficult hike to the summit accompaniment is by a mountain guide prescribed. The town of Chã das Caldeiras is connected to São Filipe , the main town on the island of Fogo, by a road via Salto and Monte Largo and can be reached by taxi, car and shared taxis ("Aluguer", once a day). On the northeast slopes of the island u. a. Coffee, beans, oranges, bananas and corn are grown. The eastern slope of the Pico is not accessible. A road leads along the coastline past the volcano to Mosteiros through a very barren landscape. The volcano can be seen well for almost the entire route.
geology
With around 30 eruptions since its discovery in the 15th century, Pico do Fogo is one of the most active oceanic stratovolcanoes on earth. The eruptions took place through the central chimney until 1769, but since 1785 using north-south oriented crevices on the flanks of the volcano. Geologically, the production products of the Pico do Fogo are included in the youngest stage of Fogos, the stage of the Chã das Caldeiras group . They follow the deposits of the Monte Amarelo Group , which came to a catastrophic end with the gigantic Young Pleistocene flank collapse around 123,000–62,000 years ago BP . Since then, the Chã das Caldeiras has gradually been filled in by the slowly growing Pico do Fogo.
Petrologically , the products produced by Pico do Fogo are undersaturated, alkaline volcanic rocks of the differentiation series basanite / tephrite / phonotephrite . Foidites that are somewhat higher in alkali also occur occasionally. The two eruptions in 1951 and 1995 also delivered these rocks. Mineralogically , these porphyry (with 15–20% by volume phenocrystals in a glassy to microcrystalline matrix) vulcanites consist of clinopyroxene , amphibole , magnetite and olivine as phenocrystals or microphenocrystals as well as clinopyroxes, magnetite and subordinate feldspar , melilite , leucite (rarely) and Amphibole in the matrix. Rarely occurring crystals of olivine and plagioclase are interpreted as xenocrystals in the phonotephrites . Apatite occurs as columnar inclusions in clinopyroxene and amphibole phenocrystals. Rare mafic xenolite inclusions are pyroxenites and pyroxen-bearing hornblendites .
Detailed thermobarometric investigations by E. Hildner et al. (2011) using fluid inclusions in clinopyroxene and olivine crystals yielded the following results for the last two eruptions of Pico do Fogo: the main magma chamber is about 16 to 24 kilometers deep, i.e. only slightly below in the uppermost lithospheric mantle the oceanic crust . In it the differentiation of the basanitic trunk magma took place through fractional crystallization. The development towards the phonotephrites is likely to have taken place in a separate area, which made a higher fractionation possible. When Magmenaufstieg it happened in the oceanic lower crust in 10 to 12 kilometer deep, a temporary stagnation ( engl. Magma ponding ) of several hours to days.
swell
- Attila Bertalan, Lucete Fortes, Pitt Reitmaier: Goldstadt hiking map Fogo-Brava , Goldstadt-Verlag, ISBN 3-89550-471-8
- Susanne Lipps, Oliver Breda: Hiking on the Cape Verde Islands , Dumont Buchverlag, ISBN 3-7701-5368-5
- Pitt Reitmaier, Lucete Fortes: Travel Guide Cabo Verde, Cape Verde Islands Verlag Reise Know How, ISBN 978-3-8317-1547-3
Web links
- Pico do Fogo in the Global Volcanism Program of the Smithsonian Institution (English)
- Rolf Cosar Photos: Vulkanfascination: Pico do Fogo 2010
Individual evidence
- ↑ Vulcao do Fogo entra em erupção - Report on the latest outbreak on bravanews.com, November 23, 2014; accessed on November 23, 2014 (Portuguese)
- ↑ Lava do vulcão do Fogo destruiu Portela e invadiu 70% de Bangaeira , Journal de Notícias, December 7, 2014 (Portuguese)
- ↑ Erupção na Ilha do Fogo agrava-se e autoridades preparam evacuações , Publico, December 8, 2014, accessed on December 11, 2014 (Portuguese)
- ↑ L'éruption du Pico do Fogo du 23.11.2014 - l'éruption oublie…. , Blog paysages on LeMonde.fr, December 10, 2014, accessed on December 11, 2014 (French)
- ↑ retour sur le vieil homme - le Pico do Fogo , blog paysages on LeMonde.fr, April 26, 2015, accessed on April 30, 2015 (French)
- ↑ Torres, P. et al .: Carta geológica das erupções históricas da Ilha do Fogo: revisão e actualização . Ed .: Réffega, A. et al. Ministério da Ciencia e da Tecnologia, Instituto de Investigação Científica Tropical. Lisbon 1997, p. 119-132 .
- ↑ Kokfelt, T .: A geochemical and isotopic study of the Island of Fogo, the Cape Verde Islands . In: PhD thesis. University of Copenhagen . 1998, p. 164 .
- ↑ Hildner, E., Klügel, A. & Hauff, F .: Magma storage and ascent during the 1995 eruption of Fogo, Cape Verde Archipelago . In: Contributions to Mineralogy and Petrology . 2011.