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57-448: The Andean Volcanic Belt and the Wansu mountain range traverse the province. Some of the highest peaks of the province are listed below: The province is divided into eight districts which are: The province is inhabited by indigenous citizens of Quechua descent. Spanish , however, is the language which the majority of the population (73.02%) learnt to speak in childhood, 26.37% of

114-568: A National Wildlife Reserve by the Ecuadorian government in 1975. This became Sangay National Park in 1979, which was expanded in 1992. The United Nations added it to their list of World Heritage Sites in 1983. From 1992 to 2005, poaching and human development led the UN to consider the site as being endangered but removed this status in 2005. The modern native inhabitants of the region primarily consist of Quechua people . The name Sangay comes from

171-412: A brief pause, it erupted again on August 8, 1934, and has not completely quelled ever since, with heavy eruptive periods occurring in 1934–1937 and 1941–1942. Eruptions at Sangay exhibit strombolian activity, producing ashfall , lava flows , pyroclastic flows , and lahars . All known eruptions at the volcano have had a Volcanic Explosivity Index (VEI) of 3 or less. Despite its activity, Sangay

228-425: A catastrophic collapse that created a debris avalanche 5 km (3 mi) wide and up to 20 km (12 mi) in length. It was likely less voluminous than the volcano's first version, and its summit lay near Sangay's current summit. Sangay currently forms an almost perfect glacier -capped cone 5,286 m (17,343 ft) high, with a 35° slope and a slight northeast-southwest tilt. Its eastern flank marks

285-811: A distance of well over 870 mi (1,400 km) . The arc has formed due to the 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 Fernández Ridge , which is believed to have produced a volcanic gap called the Pampean flat-slab segment in the Norte Chico region since

342-484: A large geothermal province, with numerous hot springs , solfataras and geysers associated with its volcanoes. Already in the pre-Columbian era, the indigenous peoples used the various hot springs as places of healing. The geothermal exploration in the Chilean Andes was pioneered in the 1960s, although the site of El Tatio was investigated previously in the 1920s. Compared to neighboring Central America ,

399-487: A large part of its southern caldera wall to slide off the mountain, forming an embayment lower on its slopes. This 400 m (1,312 ft) thick block, the best-preserved specimen of Sangay's early construction, consists of sequentially layered breccias , pyroclastic flows , and lahar deposits . Acidic andesites with just under 60% silicon dioxide dominate these flows, but more basic andesites can be found as well. Sangay's second edifice began to form anew after

456-699: A large range of crustal thicknesses and magma ascent paths and different amounts of crustal assimilations. Romeral in Colombia is the northernmost active member of the Andean Volcanic Belt. South of latitude 49° S within the Austral Volcanic Zone volcanic activity decreases with the southernmost volcano Fueguino in Tierra del Fuego archipelago. The Andean Volcanic Belt is segmented into four main areas of active volcanism;

513-586: A narrowing of the southern SVZ that occurred possibly 1.6 million years ago. The southern part of the SVZ retained vigorous activity only in the west, especially around the Liquiñe-Ofqui Fault Zone , while eastern volcanoes such as Tronador and Cerro Pantoja became extinct. The magmas of modern ( Holocene ) volcanoes in the Transitional Southern Volcanic Zone are derived from heterogenous sources in

570-453: A pristine ecology relatively untouched by human interaction, and the park hosts a biome ranging from alpine glaciers on the volcanoes' peaks to tropical forest on their flanks. Altitude and rainfall are the most significant local factors affecting fauna, and therefore the lushest ecosystems are found on the wetter parts of the volcano's eastern slope. The highest level below the snowline is dominated by lichen and bryophytes . Below this lies

627-461: A region devoid of volcanism due to a lower subduction angle caused by the subduction of Juan Fernández Ridge . The CVZ is characterized by a continental crust that reaches a thickness of approximately 70 km (43 mi). 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

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684-506: A significant distance. Mainly andesitic in composition, Sangay is highly active . The earliest report of a historical eruption was in 1628; ash fell as far away as Riobamba , located 50 km (31 mi) northwest of Sangay, and was severe enough to cover pastures and starve local livestock. The volcano erupted again in 1728, remaining essentially continuously active through 1916, with particularly heavy activity in 1738–1744, 1842–1843, 1849, 1854–1859, 1867–1874, 1872, and 1903. After

741-401: A volcano belongs to, there are significant differences within volcanic zones and even between neighboring volcanoes. Despite being a type location for calc-alkalic and subduction volcanism, the Andean Volcanic Belt has a broad range of volcano-tectonic settings, as it has rift systems and extensional zones, transpressional faults, subduction of mid-ocean ridges and seamount chains as well as

798-513: A zone of small trees and shrubs which develops into montane forest , principally in western valleys and on well-irrigated eastern slopes, which occurs below 3,750 m (12,303 ft). Tree heights develop from 5 m (16 ft) near the top to up to 12 m (39 ft) below 3,000 m (9,843 ft); below 2,000 m (6,562 ft), subtropical rainforest is present, with temperatures between 18 and 24 °C (64 and 75 °F) and up to 500 cm (196.9 in) of rainfall. Fauna

855-625: 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 (1,000 km) . 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 . Volcanism in

912-543: Is a volcanic arc in western South America and 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 is limited by the Pampean flat-slab segment or Norte Chico flat-slab segment ,

969-446: Is estimated that this cluster of urban settlements were inhabited between about 500 BCE to sometime between 300 and 600 CE. Altogether the cities may have reached a population between 15,000 and 100,000 people. They were surrounded by agricultural fields that archaeologist Stéphen Rostain speculates may have been particularly productive because their proximity to Sangay. Seventeen additional archaeological sites had been located prior to

1026-404: Is located in a remote, uninhabited region; only a large Plinian eruption could threaten occupied areas 30–100 km (19–62 mi) to its west. Nonetheless, a flank collapse on its eastern side, possible given the volcano's construction and history, could displace nearby forest and possibly affect settlements. Access to the volcano is difficult, as its current eruptive state constantly peppers

1083-411: Is more thermally stable than the northern rock, and to this is attributed the long break in volcanic activity in the Andes; Sangay occupies a position at the boundary between these two bodies, accounting for its high level of activity. Sangay developed in three distinct phases. Its oldest edifice, formed between 500,000 and 250,000 years ago, is evidenced today by a wide scattering of material opening to

1140-401: Is one of instability; two previous versions of the mountain were destroyed in massive flank collapses, evidence of which still litters its surroundings today. Due to its remoteness, Sangay hosts a significant biological community with fauna such as the mountain tapir , giant otter , Andean cock-of-the-rock and king vulture . Since 1979, its ecological community has been protected as part of

1197-607: Is similarly distributed, with distinct altitudinal zonation present. The highest altitudes support the endangered mountain tapir , cougar , guinea pig , and Andean fox . Lower down, the spectacled bear , jaguar , ocelot , margay , white-tailed deer , brocket deers , northern pudú , and endangered giant otter can all be found. Bird species common in the area include the Andean condor , Andean cock-of-the-rock , giant hummingbird , torrent duck , king vulture , and swallow-tailed kite . Sangay can be and has been climbed . It

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1254-623: Is sourced from the Amazon rainforest. Observed rainfall averages from 4,827 mm (190.0 in) per year at Pastaza to the northeast of the volcano to 423 mm (16.7 in) at Riobamba just 20 km (12 mi) west of the summit in the rain shadow . Orographic lift and the Intertropical Convergence Zone are major factors in precipitation values. Annual temperatures see little variability but diurnal changes in temperature can be wide in more arid portions of

1311-741: Is the southernmost volcano of the Northern Volcanic Zone. The Geophysics Institute at the National Polytechnic School in Quito , Ecuador houses an international team of seismologists and volcanologists whose responsibility is to monitor Ecuador 's numerous active volcanoes in the Andean Volcanic Belt (which is part of the Ring of Fire ) and the Galápagos Islands . The Central Volcanic Zone (CVZ)

1368-692: 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 Galán in Argentina . The South Volcanic Zone (SVZ) extends roughly from Central Chile's Andes at the latitude of Santiago , at ca. 33°S, to Cerro Arenales in Aysén Region at ca. 46°S,

1425-579: The Andean cordillera in Argentina , Bolivia , Chile , Colombia , Ecuador , and Peru . It is formed as a result of subduction of the Nazca plate and Antarctic plate underneath the South American plate . The belt is subdivided into four main volcanic zones which are separated by volcanic gaps . The volcanoes of the belt are diverse in terms of activity style, products, and morphology. While some differences can be explained by which volcanic zone

1482-1034: The Cordillera Real while in Colombia they are located in the Western and Central Ranges . The Pliocene Iza-Paipa volcanic complex in Boyacá , in the Eastern Ranges is the northernmost manifestation of the Northern Andean Volcanic Belt. The volcanic arc has formed due to subduction of the Nazca plate underneath western South America. Some volcanoes of the Northern Volcanic Zone, such as Galeras and Nevado del Ruiz that lie in densely populated highland areas, are significant sources of hazards. It has been estimated that crustal thickness beneath this region varies from around 40 to perhaps more than 55 kilometres (34 mi). Sangay

1539-861: The Earth's mantle . Many lesser parts of melts are derived from subducted oceanic crust and subducted sediments. Towards the east, in the backarc region, the degree of melting in the mantle that originated volcanism is less than that of the subducted crust influences. Several volcanoes of the SVZ are being monitored by the Southern Andean Volcano Observatory (OVDAS) based in Temuco . The volcanoes monitored have varied over time, but some, like Villarrica and Llaima , are monitored constantly. In recent years, there have been major eruptions at Chaitén (2008–2010), Cordón Caulle (2011) and Calbuco (2015). The Austral Volcanic Zone (AVZ)

1596-472: The Equator . It is disputed whether or not the volcano has a glacier though ice and snowfields are present. The snow line in this part of South America lies approximately 4,800 m (15,700 ft) above sea level. The mountain environment leads to significant changes in precipitation across short distances. Prevailing winds are out of the east, causing rainfall to be greatest to the east where moisture

1653-581: The Liquiñe-Ofqui Fault . The Principal Cordillera of Andes (east Santiago) rose in late Cenozoic and became extensively glaciated about one million years ago. This meant lavas from NSVZ volcanoes begun to be channeled along a network of glacial valleys ever since. The Maipo caldera exploded about 450 thousand years ago, leaving behind copious amounts of ash and ignimbrite rock that can be observed today both in Chile and Argentina. During

1710-751: The Northern Volcanic Zone , a subgroup of Andean volcanoes whose northern limit is Nevado del Ruiz in Colombia . The next active volcano in the chain, Sabancaya , is in Peru , 1,600 km (990 mi) to the south. Sangay is above a seismogenic tectonic slab about 130 km (80 mi) beneath Sabancaya, reflecting a sharp difference in the thermal character of the subducted oceanic crust , between older rock beneath southern Ecuador and Peru (dated more than 32 million years old), and younger rock under northern Ecuador and Colombia (dated less than 22 million years old). The older southern rock

1767-487: The Pliocene , the SVZ south of 38°S consisted of a broad volcanic arc. The area with volcanic activity 1 to 2 million years ago between 39°S-42°S was up to 300 km (190 mi) wide (if back-arc volcanism is included). A reduction in the convergence rate of the Nazca and the South American plate from 9 cm (3.5 in) per year to 7.9 cm (3.1 in) per year 2–3 million years ago contributed to

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1824-704: The Quaternary . Notable back-arc volcanoes include Payun Matru , Agua Poca , Payun Liso , Pali-Aike Volcanic Field , Tromen , Cochiquito Volcanic Group and Puesto Cortaderas . Other significant back-arc volcanism regions include the Argentine Northwest where the Galán Caldera is located and the Andean foothills of Ecuador's Cordillera Real , where a series of alkaline volcanoes like Sumaco develops. The Andean Volcanic Belt represents

1881-658: The Quechuan languages and is translated as "the frightener." Sangay is on the eastern edge of the Andes Mountains in central Ecuador about 160 km (99 mi) south of Quito and 20 km (12 mi) east of Riobamba . It lies within Sangay National Park. Two nearby volcanoes, Tungurahua and El Altar , are also located within the national park. The three volcanoes reach exceed 5,000 m (16,000 ft) above sea level with El Altar being

1938-481: The Sangay National Park . Although climbing the mountain is hampered by its remoteness, poor weather conditions, river flooding, and the danger of falling ejecta , the volcano is regularly climbed, a feat first achieved by Robert T. Moore in 1929. Folklore sourced from native people in the region compared Sangay to a lighthouse surrounded by a sea, which represented the dense jungle. The density of

1995-473: The 2024 announcement including potential monuments. An estimated 30,000 people lived in the region before Spanish occupation began in 1534. The Spanish prospected for gold on and around the volcano through the 16th and 17th Centuries and settled the area but expeditions undertaken in the 19th Century noted no inhabitants nearby. Modern development of the eastern side of the volcano began in the early 20th Century. The volcano and lands surrounding it were placed in

2052-478: The Andean region is poorly explored and exploited for geothermal resources. Sangay Sangay (also known as Macas , Sanagay , or Sangai ) is an active stratovolcano in central Ecuador . It exhibits mostly strombolian activity. Geologically, Sangay marks the southern boundary of the Northern Volcanic Zone , and its position straddling two major pieces of crust accounts for its high level of activity. Sangay's approximately 500,000-year-old history

2109-650: The Andes. Tibaldi et al. concluded that the magma path distribution is actually controlled by pre-existing structures and crustal weaknesses in the crust rather than the regional stresses. Back-arc volcanism is a significant phenomenon in Argentine Patagonia and Mendoza Province . Flat-slab subduction along the Peru–Chile Trench during the Miocene has been pointed out as being responsible for back-arc volcanism in Mendoza and Neuquén Province during

2166-650: The Austral Volcanic Zone is less vigorous than in the Southern Volcanic Zone. Recorded eruptions are rare due to the area being unexplored well into the 19th century; the cloudy weather of its western coast might also have prevented sightings of eruptions. The Austral Volcanic Zone hosts both glaciated stratovolcanoes as well as subglacial volcanoes under the Southern Patagonian Ice Field . The different volcanic zones are intercalated by volcanic gaps, zones that, despite lying at

2223-529: The Nazca and Juan Fernández Ridge are created by volcanic activity in Pacific hotspots ( Easter and Juan Fernández ) it can be said that volcanic activity in the Pacific is responsible for the suppression of volcanism in parts of the Andes. The Patagonian gap is different in nature as it is caused not by the subduction of an aseismic ridge but by the subduction of the Chile Rise , the boundary ridge between

2280-685: The Nazca and the Antarctic plate. Between the latitudes of 3 °S–15 °S in Peru the last volcanic activity occurred 2.7 million years ago in Cordillera Blanca . The lack of volcanism in central and northern Peru is widely attributed to a side effect of the flat-slab (low angle) subduction of the Nazca plate occurring there. While the subduction of the Nazca Ridge has often been credited for causing this flat-slab and hence

2337-603: The Northern, Central, Southern, and Austral volcanic zones, each of which is a separate continental volcanic arc . The Northern Volcanic Zone (NVZ) extends from Colombia to Ecuador and includes all volcanoes on the continental mainland of these countries. Of the volcanoes in this zone, 55 are located in Ecuador, while 19 are in Colombia. In Ecuador, the volcanoes are located in the Cordillera Occidental and

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2394-540: The Southern from the Austral Volcanic Zone. The Peruvian and Pampean gaps coincide with areas of flat slab (low angle) subduction and therefore the lack of volcanism is believed to be caused by the shallow dip of the subducting Nazca plate in these places. The shallow dip has in turn been explained by the subduction of the Nazca Ridge and the Juan Fernández Ridge for the Peruvian and Pampean gaps respectively. Since

2451-536: The United States' National Weather Service issued an ashfall advisory as the volcano went into a state of unrest, producing a plume of volcanic ash. Mariners traveling in the vicinity were cautioned about the possibility of debris. Sangay is one of two active volcanoes in the Sangay National Park, the other being Tungurahua to the north. As such it has been listed as a UNESCO World Heritage Site since 1983. The area's isolation has allowed it to maintain

2508-418: The east, defined by a crest about 4,000 m (13,120 ft) high, pockmarked by secondary ridges; it is thought to have been 15–16 km (9–10 mi) in diameter, with a summit 2 to 3 km (1 to 2 mi) southeast of the present summit. The curved shape of the remnants of this first structure shows that it suffered a massive flank collapse, scattering the nearby forest lowlands with debris and causing

2565-620: The edge of the Amazon Rainforest , and its western flank is a flat plain of volcanic ash , sculpted into steep gorges up to 600 m (1,970 ft) deep by heavy rainfall. It has a west-east trending summit ridge , capped by three active craters and a lava dome . Sangay has been active in its current form for at least 14,000 years, and is still filling out the area left bare by its earlier incarnations, being smaller than either of them. Uniquely, in its 500,000 years of activity, its magma plume has never changed composition or moved

2622-471: The jungle caused people to lose their way, but seeing ash and steam emissions from the volcano would help orient travelers along their way. Scientists have interpreted folklore like this as evidence of frequent and long-lasting eruptive activity at Sangay. In January 2024, archaeologists announced the discovery of archaeological sites on the east side of the volcano known as the Upano Valley sites . It

2679-637: The lack of volcanism, many researchers find the gap too wide to be explained by this alone. One hypothesis claims that the flat-slab is caused by the ongoing subduction of an oceanic plateau . This hypothetical plateau named Inca Plateau would be a mirror image of the Marquesas Plateau in the South Pacific. The Pampean gap or Norte Chico separates the Andes Central and Southern volcanic zones. A low subduction angle caused by

2736-731: 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. From north to south the Southern Volcanic Zone is divided into four segments according to the characteristics of the continental crust , volcanoes and volcanic rocks : In Central Southern Volcanic Zone and Southern Southern Volcanic Zone, magma ascent occur primarily by

2793-460: The massif with molten rock and other ejecta . For these reasons it is not nearly as well-studied as other, similarly active volcanoes in the Andes and elsewhere; the first detailed study of the volcano was not published until 1999. The current phase of the ongoing eruption began on 26 March 2019, and it has remained in continuing eruption status (intermittent eruptive events without a break of 3 months or more) as of January 2024. On 15 June 2022,

2850-418: The massive sector collapse that damaged the first, being constructed between 100,000 and 50,000 years ago. Remnants of its second structure are within the southern and eastern parts of the debris from its first collapse; some remnants of the volcano lie to the west and north as well. Sangay's second structure is believed to have had an east-to-west elongated summit, and like its first summit structure, it suffered

2907-422: The maximum stress is oriented in the east–west direction as the Nazca plate is subducted underneath the South American plate in the eastern direction. Recent studies conducted by Tibaldi et al. have discovered that the magma paths and dyke distribution in the Andean Volcanic Belt are not parallel to the maximum stress (E-W direction). Instead, the magma path generally follows a north–south/Northwest-Southeast trend in

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2964-537: The mountain's slopes. Higher elevations never rise above 0 °C (32 °F). Climate change threatens the snowpack and the high altitude grasslands. Lying at the eastern edge of the Andean cordillera , Sangay was formed by volcanic processes associated with the subduction of the Nazca Plate under the South American Plate at the Peru–Chile Trench . It is the southernmost volcano in

3021-456: The residents started speaking using the Quechua language ( 2007 Peru Census ). 15°50′21″S 72°39′05″W  /  15.839264°S 72.651358°W  / -15.839264; -72.651358 This Arequipa Region geography article is a stub . You can help Misplaced Pages by expanding it . Andean Volcanic Belt The Andean Volcanic Belt is a major volcanic belt along

3078-595: The right distance from an oceanic trench, lack volcanic activity. The Andes has three major volcanic gaps the Peruvian flat-slab segment (3 °S–15 °S), the Pampean flat-slab segment (27 °S–33 °S) and the Patagonian Volcanic Gap (46 °S–49 °S). The first one separates the Northern from the Central Volcanic Zone, the second the Central from the Southern and the last separates

3135-404: The subduction of Juan Fernández Ridge has been pointed out as causing or contributing to the suppression of volcanism. The distribution of magma paths in a volcanic system are typically controlled by the regional tectonic activity. In a typical setting, the magma path is thought to be parallel to the maximum stress (either in compressional or extensional stress regimes). In the case of the Andes,

3192-719: The tallest. The principal rivers draining Sangay are the Llushin, Palora , and the Upano , each of which have numerous smaller tributaries on the middle and upper slopes. Flash flooding from significant rainfall is frequent and erosion is a problem despite thick forests. Rivers drain east into the Amazon Basin . Topography is dominated by volcanic and glacial features. Hanging valleys from prior glaciation feature numerous waterfalls and lakes. Sangay reaches high enough to enjoy snow cover on its upper slopes despite its location near

3249-485: Was first ascended in 1929 by Robert T. Moore , prior to its current eruption beginning in 1934. However, the volcano's current active state presents dangers to mountaineers in the form of falling ejecta ; in 1976, two members of an expedition on the volcano were struck and killed by falling debris. In addition, the volcano is located in a remote region with poor roads and is difficult to access, and periods of heavy rainfall can flood rivers and cause landslides , rendering

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