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Sete Cidades (Ponta Delgada)
Sete Cidades is a civil parish in the center of the municipality of Ponta Delgada, that is likewise located in the center of a massive volcanic crater three miles across, also referred to as Sete Cidades. The population in 2011 was 793, in an area of 19.19 km2. It is one of the smallest parishes of Ponta Delgada by population, although the largest in area. It contains the localities Cerrado da Ladeira, Cerrado das Freiras and Sete Cidades. History Latin origins The region received its geographic nomenclature from the Latin ''Insula Septem Civitatum'', which means Island of the Seven Tribes or Island of the Seven Peoples (Portuguese: ''Ilha das Sete Tribos'' or ''Ilha dos Sete Povos''), but became a historical reference as the Island of the Seven Cities. This comes from classical Latin, probably incorporated into the older traditions of Mediterranean peoples, through the navigators of European antiquity, or the Phoenicians. In Latin, ''civitas'' does not signify ''city'', bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
São Miguel Island
São Miguel Island (; Portuguese language, Portuguese for "Saint Michael"), nicknamed "The Green Island" (''Ilha Verde''), is the largest and most populous island in the Portugal, Portuguese archipelago of the Azores. The island covers and has around 140,000 inhabitants, with 45,000 people residing in Ponta Delgada, the archipelago's largest city. History In 1427, São Miguel became the second of the islands discovered by Gonçalo Velho Cabral to be settled by colonists from continental Portugal. This date is uncertain, as it is believed that the island was discovered between 1426 and 1437 and inscribed in portolans from the middle of the 15th century. Its discovery was later recorded by Priesthood (Catholic Church), Father Gaspar Frutuoso in the seminal history of the Azores, ''Saudades da Terra'', as he began: "This island of São Miguel where...we are, is mountainous and covered in ravines, and it was, when we discovered it, covered in trees...due to its humidity, with its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
João Afonso Do Estreito
João Afonso do Estreito, from Funchal, Madeira, was a partner and co-captain in the Dulmo-Estreito expedition of 1487, a proposed pre-Columbian voyage of exploration across the Atlantic. Although licensed by King João II of Portugal, there is no evidence that the voyage ever took place. Estreito partnered up with the Flemish Fernão Dulmo (Ferdinand Van Olm), and asked João II to approve their 40-day voyage to the fabled island Antillia, which the Portuguese called the ''Seven Cities''. The King agreed to fund the exploration, under certain circumstances: Dulmo shall command the fleet to Antillia for the first forty days, and Estreito shall take over afterwards and be responsible for everything discovered until their return home. The Dulmo-Estreito voyage sparked an intense interest in later Portuguese westward voyages. Christopher Columbus had also proposed a similar journey to João II, yet his bargain was inferior to that of Dulmo. The king's rejection of Columbus left him ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mosteiros (Ponta Delgada)
Mosteiros is a civil parish in the municipality of Ponta Delgada on the Portuguese island of São Miguel in the Azores. The population in 2011 was 1,123, in an area of . It contains the localities Chã das Machadas, Lomba dos Homens, Lombinha and Mosteiros. History It was only around 1480, that the first people began to settle this part of the island, mostly by the maritime access, for many years. The community of Mosteiros was built on ancestral fishing for many years, even as its territory was cultivated by farmers. The name Mosteiros, meaning monastery in the Portuguese language, refers to nearby islets: the largest of these islets is shaped like a church.DRAC (2010), p.30 As Gaspar Frutuoso noted: :''"Between the large islet and ponta Ruiva, by the cliffs, until the promontory of Escalvados, there are some large depressions and well made fumaroles, in the form of a church, or monasteries, or of both things, that older settlers called ''the monasteries'' osteiros situated on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Dome
In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on Earth are lava dome forming. The geochemistry of lava domes can vary from basalt (e.g. Semeru, 1946) to rhyolite (e.g. Chaiten, 2010) although the majority are of intermediate composition (such as Santiaguito, dacite-andesite, present day) The characteristic dome shape is attributed to high viscosity that prevents the lava from flowing very far. This high viscosity can be obtained in two ways: by high levels of silica in the magma, or by degassing of fluid magma. Since viscous basaltic and andesitic domes weather fast and easily break apart by further input of fluid lava, most of the preserved domes have high silica content and consist of rhyolite or dacite. Existence of lava domes has been suggested for some domed structures on the Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trachytic
Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava enriched with silica and alkali metals. It is the volcanic equivalent of syenite. Trachyte is common wherever alkali magma is erupted, including in late stages of ocean island volcanismMacDonald 1983, pp. 51-52 and in continental rift valleys, above mantle plumes,Philpotts and Ague 2009, pp. 390-394 and in areas of back-arc extension. Trachyte has also been found in Gale crater on Mars. Trachyte has been used as decorative building stone and was extensively used as dimension stone in the Roman Empire and the Republic of Venice. Chemical composition Trachyte has a silica content of 60 to 65% and an alkali oxide content of over 7%. This gives it less SiO2 than rhyolite and more (Na2O plus K2O) than dacite. These chemical differences are consistent with the position ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek grc, label=none, πλεῖστος, pleīstos, most and grc, label=none, καινός, kainós (latinized as ), 'new'. At the end of the preceding Pliocene, the previously isolated North and South American continents were joined by the Isthmus of Panama, causing Great American Interchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroclastic Cone
Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption. Types of volcanic cones include stratocones, spatter cones, tuff cones, and cinder cones. Stratocone Stratocones are large cone-shaped volcanoes made up of lava flows, explosively erupted pyroclastic rocks, and igneous intrusives that are typically centered around a cylindrical vent. Unlike shield volcanoes, they are characterized by a steep profile and periodic, often alternating, explosive eruptions and effusive eruptions. Some have collapsed craters called calderas. The central core of a stratocone is commonly dominated by a central core of intrusive rocks that range from around to over several kilometers in diameter. This central core is surrounded by multiple generations of lava f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1. It is considered by some to be an interglacial period within the Pleistocene Epoch, called the Flandrian interglacial.Oxford University Press – Why Geography Matters: More Than Ever (book) – "Holocene Humanity" section https://books.google.com/books?id=7P0_sWIcBNsC The Holocene corresponds with the rapid proliferation, growth and impacts of the human species worldwide, including all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban living in the present. The human impact on modern-era Earth and its ecosystems may be considered of global si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is gone. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface (from one to dozens of kilometers in diameter). Although sometimes described as a Volcanic crater, crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur each century, the formation of a caldera is a rare event, occurring only a few times per century. Only seven caldera-forming collapses are known to have occurred between 1911 and 2016. More recently, a caldera collapse occurred at Kīlauea, Hawaii in 2018. Etymology The term ''caldera'' comes from Spanish language, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygenetic Volcanic Field
A polygenetic volcanic field is a group of polygenetic volcanoes, each of which erupts repeatedly, in contrast with monogenetic volcanoes, each of which erupts only once. Polygenetic volcanic fields generally occur where there is a high-level magma chamber. These volcanic fields may show lithological discontinuities due to major changes in magma chemistry, volcanotectonic events, or long erosional intervals, and may last over 10 million years. Unlike monogenetic volcanoes, polygenetic volcanoes reach massive sizes, such as Mauna Loa, which is the world's largest active volcano. Polygenetic volcanoes include stratovolcanoes, complex volcanoes, somma volcanoes, shield volcanoes and caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...s. References Volcanology {{Vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sete Cidades Massif
Sete Cidades Massif is a stratovolcanic complex, referring to a polygenetic volcano and caldera, located in western part of the island of São Miguel, in the Portuguese archipelago of the Azores. More recognizable for the Lagoa das Sete Cidades at its centre, the volcanic complex includes centuries of geomorphological structures that include lava domes, cones, lava flows and maar geomorphology that have marked its history. History The almost circular caldera is a nested structure formed as a result of three separate caldera collapse episodes,Robert B. Moore (1990), p.603 each associated with explosive eruptions.Jose Pacheo et al. (2002), p.4-5 These caldera collapse episodes occurred following explosive eruptions that formed the ''Risco'', ''Bretanha'' and ''Santa Barbara'' pyroclastic fields.Jose Pacheo et al. (2002), p.5-6 The first phase occurred 35,700 years ago, and ceased with the collapse of the principal volcano. A secondary phase began around 28,750 years ago and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
