Andean Volcanic Belt
The Andean Volcanic Belt is a major volcanic belt along the Andean cordillera in Colombia, Bolivia, Peru, Ecuador, Chile and Argentina. It formed as a result of subduction of the Nazca Plate and Antarctic Plate underneath the South American Plate. The belt contains many active and dormant volcanoes. Nevado del Ruiz is the northernmost member of the Andean Volcanic Belt, and probably one of the most famous, owing to its devastating eruption and lahars of 1985.
The belt, with its high level of activity is used to provide hot water and power to sparsely populated homes in the area with the possibilities of further development. Despite being a type location for calk-alkalic and subduction volcanism the Andean Volcanic Belt has a large range of volcano-tectonic settings, such as rift systems and extrensional zones, transpressional faults, subduction of mid-ocean ridges and seamount chains apart from a large range on crustal thicknesses and magma ascent paths, and different amount of crustal assimilations as diverse well climates.
Northern Volcanic Zone
The Northern Volcanic Zone (NVZ) is a volcanic arc in northwestern South America and one of the four volcanic zones of the Andes. The Northern Volcanic Zone extends from Colombia to Ecuador and include all volcanoes on the continental mainland of these countries. The volcanic arc has formed due to subduction of the Nazca Plate under western South America.
Central Volcanic Zone
The Central Volcanic Zone (CVZ) is a volcanic arc in western South America. It is one of the four volcanic zones of the Andes. The Central Volcanic Zone extends from Peru to Chile and forms the western boundary of the Altiplano plateau. The volcanic arc has formed due to subduction of the Nazca Plate under western South America along the Peru-Chile Trench. To the south the CVZ limits to the Norte Chico flat-slab segment, a region absent of volcanism due to a lower subduction angle caused by the subduction of Juan Fernandez Ridge.
The CVZ is characterized by a continental crust that reaches a thickness of approximately 70 km. Within this zone there are 44 major and 18 minor volcanic centers that are considered to be active. This volcanic zone also contains not less than six potentially active large silicic volcanic systems, which include those of the Altiplano-Puna Volcanic Complex, as are Cerro Panizos, Pastos Grandes, Cerro Guacha and La Pacana. Other silicic systems are Los Frailes ignimbrite plateau in Bolivia, and the caldera complexes of Incapillo and Cerro Galan in Argentina.
Southern Volcanic Zone
The South Volcanic Zone (SVZ), or Andean Southern Volcanic Zone, is a volcanic arc in southwestern South America. It is one of the four volcanic zones of the Andes. The SVZ extends roughly from Central Chile's Andes at the latitude of Santiago, at ca. 33S, to Mount Hudson in Aysen Region at ca. 46S, a distance of well over 870 mi . The arc has formed due to subduction of the Nazca Plate under the South American Plate along the Peru-Chile Trench. The northern boundary of the SVZ is marked by the flat-slab subduction of the Juan Fernandez Ridge, which us believed to have produced a volcanic gap called the Pampean flat-slab segment in the Norte Chico region since the late Miocene. The southern end of the SVZ is marked by the Chile Triple Junction where the Chile Rise subducts under South America at the Taitao Peninsula giving origin to the Patagonian Volcanic Gap. Further south lies the Austral Volcanic Zone.
Eight volcanoes of the SVZ are being monitored by the Southern Andean Volcano Observatory (OVDAS) based in Temuco. In recent years, there have been major eruptions at Llaima (most recently in 2008-9), and Chaiten (2008-9).
Austral Volcanic Zone
The Austral Volcanic Zone (AVZ) is a volcanic arc in the Andes of southwestern South America. It is one of the four volcanic zones of the Andes. The AVZ extends south of the Patagonian Volcanic Gap to Tierra del Fuego archipelago, a distance of well over 600 mi . The arc has formed due to subduction of the Antarctic Plate under the South American Plate. Eruption products consist chiefly of alkaline basalt and basanite.
Use of lava tubes by prehistoric man
The Pali Aike Crater is an extinct volcano cone within a series of such craters in the Pali-Aike National Park within the Austral Volcanic Zone. The locale of this crater is presently a semi-desert. The Pali Aike Crater within the Pali-Aike Volcanic Field has an extant lava tube which has yielded archaeological traces termed by C. Michael Hogan as potentially some of the earliest recoveries of prehistoric man in the Americas. This crater's lava tube along with that at Cueva Fell has been submitted to UNESCO as a possible World Heritage Site.
Massimo D'Orazio, Samuele Agostinia, Francesco Mazzarinib, Fabrizio Innocentia, Piero Manettic, Miguel J. Hallerd and Alfredo Lahsen (2000) The Pali Aike Volcanic Field, Patagonia: slab-window magmatism near the tip of South America, Tectonophysics, volume 321, Issue 4, 30 June 2000, Pages 407-427
Pali Aike National Park (2008) [*]
C. Michael Hogan (2008) Pali Aike, The Megalithic Portal, ed. A. Burnham [*]
UNESCO (1998) Submittal for inscription: Pali Aike and Fell Cave sites [*]
B and 11B behaviour in the Northern Volcanic Zone of the Andes. Insights on the devolatilization of the slab and related magma genesis processes.
Central Volcanic Zone
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