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Geology Of Panama
The geology of Panama includes the complex tectonic interplay between the Pacific, Cocos and Nazca plates, the Caribbean Plate and the Panama Microplate. Geologic history, stratigraphy, and tectonics The Cocos and Nazca plates formed in the Miocene. The Panama microplate is made of oceanic crust basalt, similar to the basalt plateau at the bottom of the Caribbean Sea. The isthmus of Panama formed due to convergent tectonics of the eastern Pacific subduction zone, which created a magmatic arc extending from southern North America. The center of the isthmus, from Arenal Volcano in Costa Rica to El Valle volcano in Panama was uplifted during the subduction of the unusually thick Cocos Ridge oceanic crust, which also produced the four kilometer high Talamanca Range. The western edge of the Caribbean Plate—the Central American Volcanic Arc—also collided in the Neogene and was compressed as the South American Plate moved northward. The El Valle volcano is the easternmost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and the Pacific Ocean to the south. Its capital and largest city is Panama City, whose metropolitan area is home to nearly half the country's million people. Panama was inhabited by indigenous tribes before Spanish colonists arrived in the 16th century. It broke away from Spain in 1821 and joined the Republic of Gran Colombia, a union of Nueva Granada, Ecuador, and Venezuela. After Gran Colombia dissolved in 1831, Panama and Nueva Granada eventually became the Republic of Colombia. With the backing of the United States, Panama seceded from Colombia in 1903, allowing the construction of the Panama Canal to be completed by the United States Army Corps of En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the west and south by the Pacific Ocean. Because it is on the North American Plate, North American Tectonic Plate, Greenland is included as a part of North America geographically. North America covers an area of about , about 16.5% of Earth's land area and about 4.8% of its total surface. North America is the third-largest continent by area, following Asia and Africa, and the list of continents and continental subregions by population, fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 579 million people in List of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's population. In Americas (terminology)#Human ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andesite
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende. Andesite is the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts, andesites are a component of the Martian crust. The name ''andesite'' is derived from the Andes mountain range, where this rock type is found in abundance. It was first applied by Christian Leopold von Buch in 1826. Description Andesite is an aphanitic (fine-grained) igneous rock that is intermediate in its content of silica and low in alkali metals. It has less than 20% quartz and 10% feldspathoid by volume, with at least 65% of the fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dacite
Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. It is composed predominantly of plagioclase feldspar and quartz. Dacite is relatively common, occurring in many tectonic settings. It is associated with andesite and rhyolite as part of the subalkaline volcanic rock, subalkaline tholeiite, tholeiitic and calc-alkaline magma series. Composition Dacite consists mostly of plagioclase feldspar and quartz with biotite, hornblende, and pyroxene (augite or enstatite). The quartz appears as rounded, corroded phenocrysts, or as an element of the ground-mass. The plagioclase in dacite ranges from oligoclase to andesine and labradorite. Sanidine occurs, although in small proportions, in some dacites, and when abundant gives rise to rocks that form rhyodacite, transitions to the rhyolites. The rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. Central America consists of eight countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. Within Central America is the Mesoamerican biodiversity hotspot, which extends from northern Guatemala to central Panama. Due to the presence of several active geologic faults and the Central America Volcanic Arc, there is a high amount of seismic activity in the region, such as volcanic eruptions and earthquakes which has resulted in death, injury, and property damage. In the pre-Columbian era, Central America was inhabited by the indigenous peoples of Mesoamerica to the north and west and the Isthmo-Colombian peoples to the south and east. Following the Spanish expedition of Christopher Columbus' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcano
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South American Plate
The South American Plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African Plate, with which it forms the southern part of the Mid-Atlantic Ridge. The easterly edge is a divergent boundary with the African Plate; the southerly edge is a complex boundary with the Antarctic Plate, the Scotia Plate, and the Sandwich Plate; the westerly edge is a convergent boundary with the subducting Nazca Plate; and the northerly edge is a boundary with the Caribbean Plate and the oceanic crust of the North American Plate. At the Chile Triple Junction, near the west coast of the Taitao–Tres Montes Peninsula, an oceanic ridge known as the Chile Rise is actively subducting under the South American Plate. Geological research suggests that the South American Plate is moving westward away from the Mid-Atlantic Ridge: "Parts of the plate boundaries consisting of alternations of relati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neogene
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene. Some geologists assert that the Neogene cannot be clearly delineated from the modern geological period, the Quaternary. The term "Neogene" was coined in 1853 by the Austrian palaeontologist Moritz Hörnes (1815–1868). During this period, mammals and birds continued to evolve into modern forms, while other groups of life remained relatively unchanged. The first humans (''Homo habilis'') appeared in Africa near the end of the period. Some continental movements took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the warm ocean currents from the Pacific to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central American Volcanic Arc
The Central American Volcanic Arc (often abbreviated to CAVA) is a chain of volcanoes which extends parallel to the Pacific coastline of the Central American Isthmus, from Mexico to Panama. This volcanic arc, which has a length of 1,100 kilometers (680 mi)Rose, W., Conway, F., Pullinger, C., Deino, A. and McIntosh, W., 1999. An improved age framework for late Quaternary silicic eruptions in northern Central America. ''Bulletin of Volcanology'', 61(1-2), pp.106-120. is formed by an active subduction zone, with the Cocos Plate subducting underneath the Caribbean Plate.Álvarez-Gómez, J., Meijer, P., Martínez-Díaz, J. and Capote, R., 2008. Constraints from finite element modeling on the active tectonics of northern Central America and the Middle America Trench. ''Tectonics'', 27(1) The region has been volcanically and geologically active for at least the past several million years. Numerous volcanoes are spread throughout various Central American countries; many have been active ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talamanca Range
The Cordillera de Talamanca is a mountain range that lies in the southeast half of Costa Rica and the far west of Panama. Much of the range and the area around it is included in La Amistad International Park, which also is shared between the two countries. This range in the south of Costa Rica stretches from southwest of San José to beyond the border with Panama and contains the highest peaks of both Costa Rica and Panama, among them Cerro Chirripó at 3,820 m, and the more accessible high peak of Cerro de la Muerte. Much of the Caribbean areas of the range are still unexplored. Exploration and classification The range is covered by the Talamancan montane forests to elevations of approximately 3,000 m. Much of it is covered by rainforests. Above elevations of 1,800 m these are dominated by huge oak trees (''Quercus costaricensis''). Above 3,000 m, the forests transition to enclaves of sub-páramo, a sort of shrub and dwarf bamboo ''Chusquea'' dominated scrub, above 3,400 m this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocos Ridge
Cocos may refer to: Geography * Cocos, Bahia, Brazil * Cocos, Quebradillas, Puerto Rico, a barrio * Cocos Island (other) ** Cocos (Keeling) Islands, a territory of Australia in the Indian Ocean *** Shire of Cocos, a local government area * Cocos Lagoon, south of Guam * Cocos Plate, a tectonic plate beneath the Pacific Ocean * rivers in Romania: ** Cocoș, a tributary of the Aita in Covasna County ** Cocoș (Constanța), a river in Constanța County ** Cocoș, a tributary of the Ilișoara Mare in Mureș County Biology * ''Cocos'' (plant), a plant genus with the coconut as its only accepted living species * '' Eoophyla cocos'', a moth of family Crambidae * '' Macrosporium cocos'', a fungus of family Pleosporaceae * '' Pseudoepicoccum cocos'', a fungus of family Incertae sedis People * Cocos Malays, an ethnic group inhabiting the Cocos (Keeling) Islands * Orang Cocos, an ethnic group in Malaysia descended from Cocos Malay immigrants * Roxana Cocoș (born 1989), Romani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectonic Uplift
Tectonic uplift is the geologic uplift of Earth's surface that is attributed to plate tectonics. While isostatic response is important, an increase in the mean elevation of a region can only occur in response to tectonic processes of crustal thickening (such as mountain building events), changes in the density distribution of the crust and underlying mantle, and flexural support due to the bending of rigid lithosphere. Tectonic uplift results in denudation (processes that wear away the earth's surface) by raising buried rocks closer to the surface. This process can redistribute large loads from an elevated region to a topographically lower area as well – thus promoting an isostatic response in the region of denudation (which can cause local bedrock uplift). The timing, magnitude, and rate of denudation can be estimated by geologists using pressure-temperature studies. Crustal thickening Crustal thickening has an upward component of motion and often occurs when continental crus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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