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Mejillones Peninsula
Mejillones Peninsula () protrudes from the coast of northern Chile north of Antofagasta and south of the port of Mejillones. The basement rocks of the peninsula are made of metamorphic and igneous rocks that formed in the Late Triassic plus plutons formed in the Early Jurassic. The eastern part of the peninsula hosts various normal faults. Extensional tectonics in the peninsula begun no later than in the Early Miocene and has resulted in the formation of two half graben basins. The uplift that the peninsula had in the Pliocene and Pleistocene has been attributed to subcrustal accretion in the subduction system. See also *Arauco Peninsula * Atacama Fault *Coastal Cliff of northern Chile *Guano Guano (Spanish from ) is the accumulated excrement of seabirds or bats. Guano is a highly effective fertiliser due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. Guano was also, to a le ... References Peninsulas of Chile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene followed the Oligocene and preceded the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by distinct global events but by regionally defined transitions from the warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and Ape, hominoids into Eurasia. During the late Miocene, the conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peninsulas Of Chile
A peninsula is a landform that extends from a mainland and is only connected to land on one side. Peninsulas exist on each continent. The largest peninsula in the world is the Arabian Peninsula. Etymology The word ''peninsula'' derives , . The word entered English in the 16th century. Definitions A peninsula is generally defined as a piece of land surrounded on most sides by water. A peninsula may be bordered by more than one body of water, and the body of water does not have to be an ocean or a sea. A piece of land on a very tight river bend or one between two rivers is sometimes said to form a peninsula, for example in the New Barbadoes Neck in New Jersey, United States. A peninsula may be connected to the mainland via an isthmus, for example, in the Isthmus of Corinth which connects to the Peloponnese peninsula. Formation and types Peninsulas can be formed from continental drift, glacial erosion, glacial meltwater, glacial deposition, marine sediment, marine transg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guano
Guano (Spanish from ) is the accumulated excrement of seabirds or bats. Guano is a highly effective fertiliser due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. Guano was also, to a lesser extent, sought for the production of gunpowder and other explosive materials. The 19th-century seabird guano trade played a pivotal role in the development of modern Intensive farming, input-intensive farming. The demand for guano spurred the human colonisation of remote bird islands in many parts of the world. Unsustainable seabird guano mining processes can result in permanent habitat destruction and the loss of millions of seabirds. Bat guano is found in caves throughout the world. Many cave ecosystems are wholly dependent on bats to provide nutrients via their guano which supports bacteria, Fungus, fungi, invertebrates, and vertebrates. The loss of bats from a cave can result in the extinction of species that rely on their guano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coastal Cliff Of Northern Chile
250px, View of the arid mountains near Iquique ending abruptly in the Pacific Ocean. The Coastal Cliff of northern Chile () stretches over a length of more than 1000 km along the Atacama Desert. It makes up a large part of the western boundary to the Chilean Coast Range in the regions of Arica y Parinacota, Tarapacá, Antofagasta, and Atacama. According to Roland Paskoff, the modern cliff originated from a scarp retreat of a fault scarp, thus at present the cliff does not follow any fault. Paskoff, R. (1979). Sobre la Evolución Geomorfológica del gran acantilado costero del Norte Grande de Chile. '' Norte Grande'' (in Spanish). Universidad Católica de Chile, Instituto de Geografía, 6, 7-22. In some locations, a series of coastal benches can be found below the cliff. Despite alternating uplift and subsidence of the continent at a decadal timescale the cliff and the whole western edge of the South American Plate The South American plate is a major tectonic plate wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atacama Fault
The Atacama Fault Zone (AFZ) is an extensive system of faults cutting across the Chilean Coastal Cordillera in Northern Chile between the Andean Mountain range and the Pacific Ocean. The fault system is north–south striking and runs for more than 1100 km North and up to 50 km in width through the Andean forearc region. The zone is a direct result of the ongoing subduction of the Eastward moving Nazca plate beneath the South American plate and is believed to have formed in the Early Jurassic during the beginnings of the Andean orogeny. The zone can be split into 3 regions: the North, Central and South. Tectonic history and formation The AFZ has gone through periods of inactivity and reactivation since its inception in the Cretaceous. The fault series was formed through a complex series of tectonic regimes dating back to the Early Jurassic, when the Andean back-arc basin separated from the Pacific Ocean. Intra-arc ductile deformation occurred in the Late Jurassic, cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arauco Peninsula
The Arauco Peninsula (Spanish: península de Arauco), is a peninsula in Southern Chile located in the homonymous Arauco Province. It projects northwest into the Pacific Ocean. The peninsula is located west of Cordillera de Nahuelbuta. Geologically it is a forearc high.Daniel Melnick, Bodo Bookhagen, Manfred R. Strecker, y Helmut P. Echtler. 2009Segmentation of megathrust rupture zones from fore-arc deformation patterns over hundreds to millions of years, Arauco peninsula, Chile. ''Journal of Geophysical Research The ''Journal of Geophysical Research'' is a peer-reviewed scientific journal. It is the flagship journal of the American Geophysical Union. It contains original research on the physical, chemical, and biological processes that contribute to the u ...'', Vol. 114. See also * Arauco Basin * Ranquil Formation References Peninsulas of Chile Landforms of Biobío Region Coasts of Biobío Region {{BíoBío-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plate, the heavier plate dives beneath the other and sinks into the mantle. A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex. The process of subduction has created most of the Earth's continental crust. Rates of subduction are typically measured in centimeters per year, with rates of convergence as high as 11 cm/year. Subduction is possible because the cold and rigid oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dense subducting lithosphere. The down-going slab sinks into the mantle largely under its own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from 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 () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58See the 2014 version of the ICS geologic time scale million years ago (Ma). It is the second and most recent epoch of the Neogene Period in the Cenozoic, Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch. Prior to the 2009 revision of the geologic time scale, which placed the four most recent major glaciations entirely within the Pleistocene, the Pliocene also included the Gelasian Stage, which lasted from 2.59 to 1.81 Ma, and is now included in the Pleistocene. As with other older geologic periods, the Stratum, geological strata that define the start and end are well-identified but the exact dates of the start a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Basin
Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock They form when long-term subsidence creates a regional depression that provides Accommodation (geology), accommodation space for accumulation of sediments. Over millions or tens or hundreds of millions of years the deposition of sediment, primarily gravity-driven transportation of water-borne eroded material, acts to fill the depression. As the sediments are buried, they are subject to increasing pressure and begin the processes of compaction (geology), compaction and lithification that transform them into sedimentary rock. Sedimentary basins are created by deformation of Earth's lithosphere in diverse geological settings, usually as a result of plate tectonics, plate tectonic activity. Mechanisms of crustal deformation that lead to subsidence and sedimentary basin formatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half Graben
A half-graben is a geological structure bounded by a fault along one side of its boundaries, unlike a full graben where a depressed block of land is bordered by parallel faults. Rift and fault structure A rift is a region where the lithosphere extends as two parts of the Earth's crust pull apart. Often a rift will form in an area of the crust that is already weakened by earlier geological activity. Extensional faults form parallel to the axis of the rift. An extensional fault may be seen as a crack in the crust that extends down at an angle to the vertical. As the two sides pull apart, the hanging wall ("hanging over" the sloping fault) will move downward relative to the footwall. A rift basin is created as the crust thins and sinks. In the rift basin, warm mantle material wells up, melting the crust and frequently triggering the eruption of volcanoes. Extensional basins may appear to be caused by a graben, or depressed block of land, sinking between parallel normal fault ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
