Macanao Peninsula
The Macanao Peninsula is a geographic peninsula landform, that forms the western end of the Isla Margarita in the Caribbean Sea, in northern Venezuela. It is also a Venezuelan municipality, the Municipality of Macanao Peninsula (''Municipio Península de Macanao''), in the state of Nueva Esparta. The municipal seat is Boca de Río. Geography The peninsula is connected to the rest of Isla Margarita by a thin strip of land in Laguna de la Restinga National Park. Sixty years ago, it was an island. The peninsula has an area of , rising from sea level to at the peak of Cerro Macanao. A ridge of high land runs along the peninsula from east to west. The main east-west crest is sharp and narrow. The mountains are smaller than in Maragarita, but are much more rugged, with many steep-sided valleys cutting through the mountain sides. The more remote beaches can only be reached via dirt roads. The climate of Margarita as a whole is hot and tropical, with little rainfall. The Macana ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Municipalities Of Venezuela
Municipality, Municipalities of Venezuela are administrative divisions of Venezuela, subdivisions of the States of Venezuela. There are 335 municipalities dividing the 23 states and the Capital District (Venezuela), Capital District. Municipalities and their seats by federal entity Capital District #Libertador Bolivarian Municipality (Caracas Libertador covers about half of the city of Caracas, officially a metropolitan area; the rest of the city is covered by four adjacent municipalities in Miranda state: Baruta, Chacao, el Hatillo and Sucre) Amazonas Anzoátegui Apure Aragua Barinas Bolívar Carabobo Cojedes Delta Amacuro Falcón Guárico Lara Mérida Miranda Monagas Nueva Esparta Portuguesa Sucre Táchira Trujillo Vargas #Vargas Municipality, Vargas (La Guaira) Yaracuy Zulia {{DEFAULTSORT:Municipalities Of Venezuela Municipalities of Venezuela, Lists of administrative divisions, Venezuela, Municipalities Subdivisions of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. The shipworms bore into wood, clay, or stone and live inside these substances. The shell of a bivalve is composed of calc ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cubagua
Cubagua Island or Isla de Cubagua () is the smallest and least populated of the three islands constituting the Venezuelan state of Nueva Esparta, after Margarita Island and Coche Island. It is located north of the Araya Peninsula, the closest mainland area. Geography Topography The island is in size, an elliptical shape with the longer axis east-west. Its area is . The coast consists of some beaches as well as cliffs from high in the south and from high in the north. The highest elevation of the flat-topped island reaches . Climate It is dry and lacks surface water bodies (the only freshwater is found in small underground reservoirs). Annual precipitation is , which is the value of a dry desert. Temperatures are close to year-round with little fluctuation. Vegetation The desert-like (xerophytic) vegetation of the essentially barren island includes a number of cactus species such as Cardón de Dato ('' Ritterocereus griseus''), Buche, Melón de Cerro, Sabana o Monte (''Mel ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Margarita Province
Margarita Province (1525 - 1864) was one of the provinces of the Spanish Empire, then one of the provinces of Gran Colombia, and later one of the Provinces of Venezuela. In Gran Colombia it belonged to the Orinoco Department which was created in 1824. With the creation of the States of Venezuela in 1864 it became Nueva Esparta. Divisions The Province was named for its most important part, Isla Margarita. Capital: Asunción Asunción (, , , Guarani: Paraguay) is the capital and the largest city of Paraguay. The city stands on the eastern bank of the Paraguay River, almost at the confluence of this river with the Pilcomayo River. The Paraguay River and the Bay o .... Cantons: * Asunción Canton * Norte Canton (seat: Santa Ana del Norte). Governors A partial list of governors: References Citations Sources * * * * * * * * 2rchivo General de Indias, CONTRATACIÓN, 5469, Nº 2, R54 Provinces of Gran Colombia Provinces of Venezuela Provinces of the Spanish Empi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Garcia Álvarez De Figueroa
Garcia Álvarez de Figueroa was a Spanish soldier who was Governor of the Margarita Province, based on Isla Margarita off the coast of what today is Venezuela, from 1626 to 1630. In December 1619 Admiral Álvarez de Figueroa was with a fleet of six galleons that set out from Cadiz with instructions to pass through the Strait of Magellan without stopping in Brazil. The fleet ran into a violent storm and was forced to run back to land, with most of the ships run aground on Cape Trafalgar and many people drowned. Only the galleon that held Admiral Garcia Alvarez de Figueroa and the cosmographer Diego Ramirez de Arellano stayed afloat. Admiral Garcia Álvarez de Figueroa was appointed Governor and Captain General of the Island of Margarita on 30 April 1625. He took over from Andrés Rodríguez de Villegas on 1 June 1626. He was accompanied by his son Gerónimo. Figueroa was known for his interest in letters, for his contempt of the local Waikerí people, and for his enjoyment of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mid-ocean Ridge
A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of about and rises about above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a divergent plate boundary. The rate of seafloor spreading determines the morphology of the crest of the mid-ocean ridge and its width in an ocean basin. The production of new seafloor and oceanic lithosphere results from mantle upwelling in response to plate separation. The melt rises as magma at the linear weakness between the separating plates, and emerges as lava, creating new oceanic crust and lithosphere upon cooling. The first discovered mid-ocean ridge was the Mid-Atlantic Ridge, which is a spreading center that bisects the North and South Atlantic basins; hence the origin of the name 'mid-ocean ridge'. Most oceanic spreading centers are not in the middle of their hosting ocean basis but regardless, are traditionally called mid-ocean rid ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Island Arc
Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle along the subduction, subduction zone. They are the principal way by which continental growth is achieved. Island arcs can either be active or inactive based on their seismicity and presence of volcanoes. Active arcs are ridges of recent volcanoes with an associated deep seismic zone. They also possess a distinct curved form, a chain of active or recently extinct volcanoes, a Oceanic trench, deep-sea trench, and a large negative Bouguer anomaly on the convex side of the volcanic arc. The small positive gravity anomaly associated with volcanic arcs has been interpreted by many authors as due to the presence of dense volcanic rocks beneath the arc. Inactive arcs are a chain of islands which contains older volcanic and volcaniclastic rocks. Th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Metabasalt
Amphibolite () is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no quartz. It is typically dark-colored and dense, with a weakly foliated or schistose (flaky) structure. The small flakes of black and white in the rock often give it a salt-and-pepper appearance. Amphibolite frequently forms by metamorphism of mafic igneous rocks, such as basalt. However, because metamorphism creates minerals entirely based upon the chemistry of the protolith, certain 'dirty marls' and volcanic sediments may also metamorphose to an amphibolite assemblage. Deposits containing dolomite and siderite also readily yield amphibolite (tremolite-schist, grunerite-schist, and others) especially where there has been a certain amount of contact metamorphism by adjacent granitic masses. Metamorphosed basalt (metabasalt) creates ''ortho-amphibolite'' and other chemically appropriate lithologies create ''para-amphibolite''. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tholeiitic
The tholeiitic magma series is one of two main magma series in subalkaline igneous rocks, the other being the calc-alkaline series. A magma series is a chemically distinct range of magma compositions that describes the evolution of a mafic magma into a more evolved, silica rich end member. Rock types of the tholeiitic magma series include tholeiitic basalt, ferro-basalt, tholeiitic basaltic andesite, tholeiitic andesite, dacite and rhyolite. The variety of basalt in the series was originally called ''tholeiite'' but the International Union of Geological Sciences recommends that ''tholeiitic basalt'' be used in preference to that term.Le Maitre ''et al.'' 2002 Tholeiitic rock types tend to be more enriched in iron and less enriched in aluminium than calc-alkaline rock types. They are thought to form in a less oxidized environment than calc-alkaline rocks. Tholeiitic basalt is formed at mid-ocean ridges and makes up much of the oceanic crust. Almost all the basalt found on the Moon ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mafic
A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium-rich varieties of plagioclase feldspar. Mafic materials can also be described as ferromagnesian. History The term ''mafic'' is a portmanteau of "magnesium" and "ferric" and was coined by Charles Whitman Cross, Joseph P. Iddings, Louis Valentine Pirsson, and Henry Stephens Washington in 1912. Cross' group had previously divided the major rock-forming minerals found in igneous rocks into ''salic'' minerals, such as quartz, feldspars, or feldspathoids, and ''femic'' minerals, such as olivine and pyroxene. However, micas and aluminium-rich amphiboles were excluded, while some calcium minerals containing little iron or magnesium, such as wollastonite or apatite, were included ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Eclogite
Eclogite () is a metamorphic rock containing garnet (almandine-pyrope) hosted in a matrix of sodium-rich pyroxene (omphacite). Accessory minerals include kyanite, rutile, quartz, lawsonite, coesite, amphibole, phengite, paragonite, zoisite, dolomite, corundum and, rarely, diamond. The chemistry of primary and accessory minerals is used to classify three types of eclogite (A, B, and C). The broad range of eclogitic compositions has led a longstanding debate on the origin of eclogite xenoliths as subducted, altered oceanic crust. Origins Eclogites typically result from high to ultrahigh pressure metamorphism of mafic rock at low thermal gradients of < as it is subducted to the lower crust to depths in a subduction zone. Class ...
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Amphibolite
Amphibolite () is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no quartz. It is typically dark-colored and dense, with a weakly foliated or schistose (flaky) structure. The small flakes of black and white in the rock often give it a salt-and-pepper appearance. Amphibolite frequently forms by metamorphism of mafic igneous rocks, such as basalt. However, because metamorphism creates minerals entirely based upon the chemistry of the protolith, certain 'dirty marls' and volcanic sediments may also metamorphose to an amphibolite assemblage. Deposits containing dolomite and siderite also readily yield amphibolite (tremolite-schist, grunerite-schist, and others) especially where there has been a certain amount of contact metamorphism by adjacent granitic masses. Metamorphosed basalt (metabasalt) creates ''ortho-amphibolite'' and other chemically appropriate lithologies create ''para-amphibolite''. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |