Gruta das Agulhas

Gruta das Agulhas
Location	Terceira Island (Azores), Portugal
Coordinates	38°38′40.51″N 27°6′18.40″W / 38.6445861°N 27.1051111°W / 38.6445861; -27.1051111
Length	250.5 metres (822 ft)
Discovery	1967
Geology	Lava tube, Basalt
Entrances	1
Access	Access restricted to public

Gruta das Agulhas (Needle Cave) is a cave located along the promontory of Ponta dos Coelhos, in the Bay of Refugo, in the civil parish of Porto Judeu, in the municipality of Angra do Heroísmo, the Portuguese archipelago of the Azores.

The cave is situated along the coast of Salga, along the high cliffs of the promontory, formed from an accumulation of lava flows.^[1] It was formed during the eruption of the volcano associated with the Algar do Carvão, which flowed to the sea, arriving at the coast of Serretinha, in the civil parish of Feteira. The flow spread to Porto Judeu, forming a coastal geomorphology of black basalt of large dimensions, arribas and coves of dangerous cliffs. As the lava, which was primarily aa and pahoehoe, flowed into these tubes slowly decreased, it left hollow caverns opening into galleries, some of various kilometres of length.^[1]

It obtained its name from the great quantity of needle-like sedimentary deposited on the rocks and ceiling of the lava tube, ranging from .2–.5 centimetres (0.079–0.197 in).^[1] The 250.5 metres (822 ft) gallery is situated over a smaller gallery that is 30 metres (98 ft) wide.^[1] The tube's extent is carved by layers (or steps) sculpted by various lava flow cycles. The Gruta das Agulhas is at its highest point 5.4 metres (18 ft) and at the widest point 4.5 metres (15 ft).^[2]

The cave was discovered and explored until its exit at the sea by the Associação Espeleológica Os Montanheiros in 1967. Since it was discovered, the cave has been studied for its varied fauna and geological importance. Of note, were species of Troglofauna, including Pseudoblothrus vulcanus, Macarorchestia martini and Pseudosinella ashmoleorum, in addition to endemic species like Phthiracarus falciformis, Orchestia chevreuxi and Pseudosinella azorica.

Eventually, the space was illuminated and an entranceway constructed to restrict access into the space by Os Montanheiros. Due to sea erosion, access was restricted to the public.

References

1 2 3 4 Paulo Barcelos (2011), p.1
↑ "Inventário do Património Espeleológico dos Açores". GESPEA - Grupo de Trabalho para o Estudo do Património Espeleológico dos Açores. Retrieved 2009-12-03.

Sources

Barcelos, Paulo (1 December 2011), Gruta das Agulhas (PDF) (in Portuguese), Horta (Azores), Portugal: SIARAM

Angra do Heroísmo

Civil parishes	Altares Cinco Ribeiras Doze Ribeiras Feteira Nossa Senhora da Conceição Porto Judeu Posto Santo Raminho Ribeirinha Santa Bárbara Santa Luzia São Bartolomeu de Regatos São Bento São Mateus da Calheta São Pedro Sé Serreta Terra Chã Vila de São Sebastião

Natural Landmarks	Algar do Carvão Bay of Angra Bay of Pontas Bay of Salga Bay of Refugo Furna de Água Galerias da Feteira Gruta Brisa Azul Gruta das Mercês Gruta do Zé Grande Gruta das Cinco Ribeiras Gruta das Agulhas Gruta dos Ratões Cabras Islets Lagoa do Negro Mata da Serreta Monte Brasil Parque de Campismo das Cinco Ribeiras Porto das Cinco Ribeiras Ponta do Queimado Prainha Serra do Morião ou da Nasce Água Serra da Ribeirinha Serra de Santa Bárbara Zona Balnear do Negrito Zona de Protecção Especial do Ilhéu das Cabras

Man-made Landmarks	Bettencourt Palace Cais da Alfândega Cais da Silveira Câmara Municipal de Angra do Heroísmo Castle of Moinhos Cemetery of Anchors Church of São Mateus da Calheta Convent of São Gonçalo Duke of Terceira Garden Fort of Má Ferramenta Fort of Negrito Fort of Santo António do Monte Brasil Fort of São João Fort of the Açougue Fort of the Cavalas Fort of the Church of São Mateus da Calheta Fort of the Maré Forte das Caninas Forte das Cinco Ribeiras Forte da Greta Forte da Salga Forte de Santa Catarina das Mós Forte de Santo António Forte de São Fernando Forte de São Francisco Forte de São Sebastião Forte do Terreiro Forte do Zimbreiro Fort of São João Baptista Fortress of São Mateus da Calheta Redoubt of Dois Paus Redoubt of Três Paus Reducto da Salga Manor of Madre de Deus Miradouro da Amoreira Miradouro do Pico das Cruzinhas Miradouro da Ponta do Queimado Miradouro do Pico Matias Simão Miradouro da Serreta Miradouro das Veredas Parque Arqueológico Subaquático da Baía de Angra do Heroísmo Parque de Campismo das Cinco Ribeiras Parque Municipal do Relvão (Angra do Heroísmo) Porto das Cinco Ribeiras Sé Cathedral of Angra do Heroísmo

This article is issued from Wikipedia - version of the Tuesday, March 01, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.