Tunupa

Last updated
Tunupa
Volcan Tunupa & Salar de Uyuni.jpg
Tunupa and Salar de Uyuni.
Highest point
Elevation 5,321 m (17,457 ft) [1]
Prominence 1,601 m (5,253 ft) [1]
Listing Ultra
Coordinates 19°49′57″S67°38′45″W / 19.83250°S 67.64583°W / -19.83250; -67.64583 Coordinates: 19°49′57″S67°38′45″W / 19.83250°S 67.64583°W / -19.83250; -67.64583 [1]
Geography
Bolivia physical map.svg
Red triangle with thick white border.svg
Tunupa
Bolivia
Location Potosí Department, Bolivia

Tunupa is a dormant volcano in the Potosí Department of southwestern Bolivia.

Contents

It stands on the northern side of the Salar de Uyuni at an elevation of 5,321 m (17,457 ft) on the Bolivian Altiplano. Tunupa was active in the Pleistocene, with most of the volcano constructed by lava flows that erupted between 1.36 and 1.56 million years ago. [2] Later glaciers developed on the mountain.

There is a cave with several mummies about half way up and an ancient village at the foot with a modest "salt hotel".

Geography and geomorphology

Tunupa is located in Bolivia, at the centre of the Altiplano about 115 kilometres (71 mi) east of the main volcanic arc. [3] It forms a peninsula in the Salar de Uyuni, [4] which surrounds the volcano on its southern side. [5] The volcano is located within the Salinas de Garci-Mendoza municipality, [6] and the towns of Ayque, Coquesa and Jirira lie on its southern slopes. [7]

Volcanism in the backarc of the Central Andes is represented by several types of volcanoes, including several monogenetic volcanoes, stratovolcanoes such as Cerro Tuzgle, Tunupa and Uturunku and large ignimbrites like Altiplano-Puna volcanic complex, Galán, Los Frailes volcanic field and Morococala. [3]

The volcano rises about 1.8 kilometres (1.1 mi) above the surrounding terrain, the summit of the volcano is heavily hydrothermally altered [3] and its summit crater degraded by erosion, with crags representing remnants of the old lava conduit. [4] Several lava domes were emplaced on top of lava flows from Tunupa on its eastern flank. Pyroclastic flows are found on the northern flank. Erosion and glaciation have generated a deposit of eroded material that surrounds much of the volcano. [3]

There is no present-day permanent ice on Tunupa [8] as the region is too dry [9] but the mountain was glaciated in the past, and large valley glaciers descended to elevations of 3,650–3,700 metres (11,980–12,140 ft) when they reached their largest extent. Later shorter glaciers reoccupied the same valleys; outwash gravel deposits are found downstream below the moraines, [10] such as below the Chalchala and Pocolli valleys on the southern flank of the volcano [11] where most glacial landforms are found. [12] Glacial landforms include glacial striae and ice drift deposits are found on the volcano, as are several extensive moraine systems. [7] Three separate stages of glaciation have been inferred at Tunupa, [12] one dating proposal dates the first advance to about 160,000 before present, the second lasts until about 15,000 years/may coincide with the existence of Lake Tauca before present and the last one occurred during the Younger Dryas. [13] [8]

The southern slopes of Tunupa are incised by the shorelines of former lakes that occupied the Altiplano, such as Lake Minchin and Lake Tauca. Crusts of algae, [14] stromatolites [15] and river deltas are also found at these former shorelines. [16] Over seven separate shoreline stages have been identified at Tunupa, [7] which was part of an island in Lake Tauca. [17] It is likely that evaporation from the lake increased precipitation at Tunupa and thus allowed glaciers to grow to larger sizes than they would have without such evaporation. [13]

Geology

Subduction has been occurring off the western margin of South America for the past 200 million years. [18] Presently, the Nazca Plate is subducting eastward below South America. [5] The subduction is responsible for the formation of the Altiplano high plateau; the Tibetan Plateau is the only other place in the world where oceanic subduction has generated a high plateau. [18]

Volcanism in the Andes occurs in a frontal volcanic arc, but also in the back-arc region. This back-arc volcanism that Tunupa is part of has an uncertain origin; one proposed process is delamination, whereby the lowermost mafic section of the crust and lithosphere underneath separates itself from the above lying layers. This separation process then triggers volcanic activity through either decompression melting, dehydration melting, increases in temperature, or some combination of these processes. [18] Back-arc volcanism in the region started about 25-30 million years ago. [3]

East of Tunupa lie the Huayrana lavas, which are much older (Potassium-argon dating has yielded an age of 11.1 ± 0.4 million years ago). Tunupa and Sillajhuay farther west form a chain of volcanoes known as the Serranía Intersalar, which lies within the so-called Pica gap where recent volcanism is rare. This chain of volcanoes was active starting from the Oligocene to the Quaternary. [3]

Composition

Tunupa is formed principally by andesite, [8] trachyandesite and trachydacite, forming a potassium-rich calc-alkaline suite. [19] The rocks contain phenocrysts of amphibole, biotite, clinopyroxene, uncommon olivine, uncommon orthopyroxene, oxides and plagioclase. [20] The lava domes are more silicic than the main volcanic edifice. [2]

An average magma output of 0.00043–0.00093 cubic kilometres per year (0.00010–0.00022 cu mi/a) has been estimated, which is comparable to Lascar and Parinacota. [19] Delamination of the crust, [21] hydration-induced melting [22] and magma mixing processes have been used to explain the magma chemistry at Tunupa. [19] It has been proposed that as the lower crust undergoes delamination, certain water-containing minerals such as amphibole and phlogopite become unstable and enrich magma with niobium, tantal and titanium. [18]

Climate

Average temperatures at Oruro are 9.5 °C (49.1 °F). While they decrease to 0 °C (32 °F) at an elevation of about 4,800 metres (15,700 ft), the dry climate of the region limits the development of glaciers; average precipitation is less than 200 millimetres per year (7.9 in/year) in the southwestern Altiplano. [17]

Eruption history

Initial Potassium-argon dating has yielded ages of 2.5 ± 0.5 and 1.8 ± 0.2 million years ago on samples from Tunupa. [3] Later performed argon-argon dating produced ages between 1.55 ± 0.01 and 1.40 ± 0.04 million years ago, [20] with even younger dates of 440,000 ± 40,000 years before present. [23] The main edifice developed first, the lava domes were emplaced later. [2] The volcano is considered to be extinct. [14]

Mythology

In Aymara legends, Tunupa is personified as a deity with varying attributes and often linked to legends about the origin of the Salar de Uyuni. [24]

See also

Related Research Articles

Parinacota (volcano) Volcano on the border of Chile and Bolivia

Parinacota, Parina Quta or Parinaquta is a dormant stratovolcano on the border of Chile and Bolivia. Together with Pomerape it forms the Nevados de Payachata volcanic chain. Part of the Central Volcanic Zone of the Andes, its summit reaches an elevation of 6,380 metres (20,930 ft) above sea level. The symmetrical cone is capped by a summit crater with widths of 1 kilometre (0.62 mi) or 500 metres (1,600 ft). Farther down on the southern slopes lie three parasitic centres known as the Ajata cones. These cones have generated lava flows. The volcano overlies a platform formed by lava domes and andesitic lava flows.

Viedma (volcano)

Viedma is a subglacial volcano whose existence is questionable. It is supposedly located below the ice of the Southern Patagonian Ice Field, an area disputed between Argentina and Chile. The 1988 eruption deposited ash and pumice on the ice field and produced a mudflow that reached Viedma Lake. The exact position of the edifice is unclear, both owing to the ice cover and because the candidate position, the "Viedma Nunatak", does not clearly appear to be of volcanic nature.

Ollagüe

Ollagüe or Ullawi is a massive andesite stratovolcano in the Andes on the border between Bolivia and Chile, within the Antofagasta Region of Chile and the Potosi Department of Bolivia. Part of the Central Volcanic Zone of the Andes, its highest summit is 5,868 metres (19,252 ft) above sea level and features a summit crater that opens to the south. The western rim of the summit crater is formed by a compound of lava domes, the youngest of which features a vigorous fumarole that is visible from afar.

Taapaca Volcano in Chile

Taapaca is a Holocene volcanic complex in northern Chile's Arica y Parinacota Region. Located in the Chilean Andes, it is part of the Central Volcanic Zone of the Andean Volcanic Belt, one of four distinct volcanic chains in South America. The town of Putre lies at the southwestern foot of the volcano.

Sollipulli Volcanic mountain in Chile

Sollipulli is an ice-filled volcanic caldera and volcanic complex, which lies southeast of the small town of Melipeuco in the La Araucanía Region, Chile. It is part of the Southern Volcanic Zone of the Andes, one of the four volcanic belts in the Andes chain.

Jayu Quta (Ladislao Cabrera) Crater in Bolivia

Jayu Quta is a maar partially filled with water, in the Bolivian Altiplano, north of the Salar de Uyuni and east of the Salar de Coipasa. It is situated in the Oruro Department, Ladislao Cabrera Province, Salinas de Garci Mendoza Municipality, Villa Esperanza Canton. It was originally misidentified as a meteorite impact crater.

Cerro Guacha

Cerro Guacha is a Miocene caldera in southwestern Bolivia's Sur Lípez Province. Part of the volcanic system of the Andes, it is considered to be part of the Central Volcanic Zone (CVZ), one of the three volcanic arcs of the Andes, and its associated Altiplano-Puna volcanic complex (APVC). A number of volcanic calderas occur within the latter.

Lake Minchin

Lake Minchin is a name of an ancient lake in the Altiplano of South America. It existed where today the Salar de Uyuni, Salar de Coipasa and Lake Poopó lie. It was formerly considered the highest lake in the Altiplano but research indicated that the highest shoreline belongs to the later Lake Tauca instead.

Lake Tauca Former lake in Bolivia, parts of it extended into Chile

Lake Tauca is a former lake in the Altiplano of Bolivia. It is also known as Lake Pocoyu for its constituent lakes: Lake Poopó, Salar de Coipasa and Salar de Uyuni. The lake covered large parts of the southern Altiplano between the Eastern Cordillera and the Western Cordillera, covering an estimated 48,000 to 80,000 square kilometres of the basins of present-day Lake Poopó and the Salars of Uyuni, Coipasa and adjacent basins. Water levels varied, possibly reaching 3,800 metres (12,500 ft) in altitude. The lake was saline. The lake received water from Lake Titicaca, but whether this contributed most of Tauca's water or only a small amount is controversial; the quantity was sufficient to influence the local climate and depress the underlying terrain with its weight. Diatoms, plants and animals developed in the lake, sometimes forming reef knolls.

Sajsi is the name of an ancient lake in the Andes

Kunlun Volcanic Group

Kunlun Volcanic Group, also known as Ashikule, is a volcanic field in northwestern Tibet. Eight other volcanic fields are also in the area. The field is within a basin that also contains three lakes.

Fueguino is a volcanic field in Chile. The southernmost volcano in the Andes, it lies on Tierra del Fuego's Cook Island and also extends over nearby Londonderry Island. The field is formed by lava domes, pyroclastic cones, and a crater lake.

Mount Erciyes

Mount Erciyes, also known as Argaeus, is a volcano in Turkey. It is a large stratovolcano surrounded by many monogenetic vents and lava domes, and one maar. The bulk of the volcano is formed by lava flows of andesitic and dacitic composition. At some time in the past, part of the summit collapsed towards the east.

Pastos Grandes

Pastos Grandes is the name of a caldera and its crater lake in Bolivia. The caldera is part of the Altiplano-Puna volcanic complex, a large ignimbrite province that is part of the Central Volcanic Zone of the Andes. Pastos Grandes has erupted a number of ignimbrites through its history, some of which exceeded a volume of 1,000 cubic kilometres (240 cu mi). After the ignimbrite phase, the lava domes of the Cerro Chascon-Runtu Jarita complex were erupted close to the caldera and along faults.

Los Frailes ignimbrite plateau

Los Frailes is an ignimbrite plateau in Bolivia, between the city of Potosi and the Lake Poopo. It belongs to a group of ignimbrites that exist in the Central Andes and which includes the Altiplano–Puna volcanic complex. The plateau covers a surface of 7,500 square kilometres (2,900 sq mi)–8,500 square kilometres (3,300 sq mi) with about 2,000 cubic kilometres (480 cu mi) of ignimbrite.

Tata Sabaya A 5,430-metre (17,810 ft) high volcan in Bolivia

Tata Sabaya is a 5,430-metre (17,810 ft) high volcano in Bolivia. It is part of the Central Volcanic Zone, one of several volcanic belts in the Andes which are separated by gaps without volcanic activity. This section of the Andes was volcanically active since the Jurassic, with an episode of strong ignimbritic volcanism occurring during the Miocene. Tata Sabaya lies in a thinly populated region north of the Salar de Coipasa salt pan.

Sillajhuay

Sillajhuay is a volcano on the border between Bolivia and Chile. It is part of a volcanic chain that stretches across the border between Bolivia and Chile and forms a mountain massif that is in part covered by ice; whether this ice should be considered a glacier is debatable but it has been retreating in recent decades.

Uturuncu

Uturunku is a dormant 6,008 metres (19,711 ft) high volcano in Bolivia with two summit peaks. It consists of a complex of lava domes and lava flows with a total volume of 50–85 cubic kilometres (12–20 cu mi) and bears traces of a former glaciation, even though it does not currently carry glaciers. Volcanic activity took place during the Pleistocene and the last eruption was 250,000 years ago; since then Uturuncu has not erupted but active fumaroles occur in the summit region.

Pasto Ventura

Pasto Ventura is an area in the Catamarca Province of Argentina. It features about 14 small Pleistocene volcanoes, mostly cinder cones with associated lava flows but also lava domes, tuff rings and two maars. The volcanoes are accompanied by pyroclastic deposits and their total volume reaches about 0.42 cubic kilometres (0.10 cu mi). Argon-argon dating has yielded ages ranging from 1.3 million years to about 270,000 years for volcanic rocks in the field.

Tocorpuri

Tocorpuri is a volcano in Chile, close to the border with Bolivia. Its peak height is most recently given as 5,808 metres (19,055 ft) and it features a 1.3 kilometres (0.81 mi) wide summit crater. The volcano consists mainly of lava flows and pyroclastic deposits and is subdivided into two separate edifices. Just west of Tocorpuri, the La Torta lava dome is a 200 metres (660 ft) high flat-topped structure. The volcanoes are formed by andesitic, dacitic and rhyolitic rocks.

References

  1. 1 2 3 "Bolivia Ultra-Prominences" Peaklist.org
  2. 1 2 3 Salisbury, Morgan. "VOLCANOLOGY AND PETROLOGY OF AN ENIGMATIC BACKARC VOLCANO ON THE BOLIVIAN ALTIPLANO: IMPLICATIONS FOR NON-SUBDUCTION RELATED VOLCANISM". gsa.confex.com.
  3. 1 2 3 4 5 6 7 Salisbury et al. 2015, p. 96.
  4. 1 2 Ahlfeld, F; Branisa, L (1960). Geologia de Bolivia. Boliviano Petróleo. p. 194.
  5. 1 2 Salisbury et al. 2015, p. 97.
  6. Чеснокова, O. C.; Радович, М.; Ледесма, Г. Техерина (20 January 2019). "OBSERVACIONES SOBRE LA TOPONIMIA BOLIVIANA". Филологические науки в МГИМО (in Spanish): 77.
  7. 1 2 3 Clapperton et al. 1997, p. 55.
  8. 1 2 3 Martin et al. 2020, p. 6.
  9. Martin et al. 2020, p. 13.
  10. Clapperton et al. 1997, p. 53,54.
  11. Clayton & Clapperton 1997, p. 173.
  12. 1 2 Clayton & Clapperton 1997, p. 171.
  13. 1 2 Blard, P.-H.; Lavé, J.; Farley, K.A.; Fornari, M.; Jiménez, N.; Ramirez, V. (December 2009). "Late local glacial maximum in the Central Altiplano triggered by cold and locally-wet conditions during the paleolake Tauca episode (17–15ka, Heinrich 1)". Quaternary Science Reviews. 28 (27–28): 3423. doi:10.1016/j.quascirev.2009.09.025. ISSN   0277-3791.
  14. 1 2 Clapperton et al. 1997, p. 52.
  15. Clayton & Clapperton 1997, p. 177.
  16. Clapperton et al. 1997, p. 54.
  17. 1 2 Clayton & Clapperton 1997, p. 170.
  18. 1 2 3 4 Salisbury et al. 2015, p. 95.
  19. 1 2 3 Salisbury et al. 2015, p. 100.
  20. 1 2 Salisbury et al. 2015, p. 98.
  21. Salisbury et al. 2015, p. 105.
  22. Salisbury et al. 2015, p. 102.
  23. Blard, P.-H.; Lavé, J.; Sylvestre, F.; Placzek, C.J.; Claude, C.; Galy, V.; Condom, T.; Tibari, B. (September 2013). "Cosmogenic 3He production rate in the high tropical Andes (3800 m, 20°S): Implications for the local last glacial maximum". Earth and Planetary Science Letters. 377–378: 267. doi:10.1016/j.epsl.2013.07.006. ISSN   0012-821X.
  24. Clark, Nicola; Wallis, Simon (1 May 2017). "Flamingos, salt lakes and volcanoes: hunting for evidence of past climate change on the high Altiplano of Bolivia". Geology Today. 33 (3): 104. doi:10.1111/gto.12186. ISSN   1365-2451.

Sources