Jump to content

Aucanquilcha

Coordinates:21°11′S68°35′W/ 21.183°S 68.583°W/-21.183; -68.583
This is a good article. Click here for more information.
From Wikipedia, the free encyclopedia

Aucanquilcha
A flat mountain massif over a plain
View of Aucanquilcha volcano from the northwest
Highest point
Elevation6,176 m (20,262 ft)[1]
Prominence2,145 m (7,037 ft)[2]
Parent peakHuascaran
Coordinates21°11′S68°35′W/ 21.183°S 68.583°W/-21.183; -68.583[3]
Naming
EtymologyQuechua:Auqa/aukka;"cruel" / "enemy",kichka/khiska;"spine"; "cruel spine"[4]
PronunciationOW-kahn-KEEL-chuh
Geography
Aucanquilcha is located in the northernmost part of Chile
Aucanquilcha is located in the northernmost part of Chile
Aucanquilcha
Parent rangeAndes
Geology
Age of rockUp to 11 Ma (Late Miocene)
Mountain typeStratovolcano
Type of rockDacite
Volcanicarc/beltCentral Volcanic Zone
Last eruption240,000 ± 50,000 years ago (Pleistocene)[5]

Aucanquilchais a massivestratovolcanolocated in theAntofagasta Regionof northernChile,just west of the border withBoliviaand within theAlto Loa National Reserve.Part of theCentral Volcanic Zoneof theAndes,the stratovolcano has the form of a ridge with a maximum height of 6,176 metres (20,262 ft). The volcano is embedded in a larger cluster of volcanoes known as the Aucanquilcha cluster. This cluster of volcanoes was formed in stages over eleven million years of activity with varying magma output, includinglava domesandlava flows.Aucanquilcha volcano proper is formed from four units that erupted between 1.04–0.23 million years ago. During theice ages,both the principal Aucanquilcha complex and the other volcanoes of the cluster were subject toglaciation,resulting in the formation ofmorainesandcirques.

The cluster has generated lava ranging in composition fromandesitetodacite,with the main volcano being exclusively of dacitic composition. Systematic variations in temperature, crystal andbiotitecontent have been recorded during the evolution of the cluster.

At Aucanquilcha volcano there is somefumarolicactivity, andsulfurdeposits are found at the summit. Several sulfur mines lie in the complex. One mine at an altitude of 5,950 metres (19,520 ft) was opened in 1913 and remained in use from 1950 to 1992. It was the world's highest mine during that period. Originally, sulfur obtained at the mine was transported down withllamas.Subsequently, anaerial cablewaywas employed to transport the sulfur to the town ofAmincha.To bring the sulfur down, a road network to the summit was constructed in 1972, although it is now impassable.

In 1986, four men were reported to be living at an altitude of 5,900 metres (19,400 ft), making them the highest permanent residents on Earth.

Geography and geology

[edit]

Regional setting

[edit]
Main articles:Andean Volcanic BeltandAltiplano–Puna volcanic complex

Aucanquilcha is part of theCentral Volcanic Zone(CVZ) of theAndes,a highlysilicicvolcanic zone in South America. The CVZ generates magmas at a rate of 0.11 cubic kilometres per millennium (0.026 cubic miles per millennium), one tenth of the global average ofarc magmaproduction, and lies about 135–180 kilometres (84–112 mi) above theWadati–Benioff zone.The arc has migrated eastward towards the high Andes from the Pacific Ocean coast since theJurassic.The arc containsandesiticvolcanoes,ignimbritesandcompound volcanoesand has generated over 3,000 cubic kilometres (720 cu mi) of eruption products over 28 million years.[5]

The Aucanquilcha complex lies northwest of theAltiplano–Puna volcanic complex(APVC), a locallarge igneous province.The APVC is underpinned below at a depth of 20 kilometres (12 mi) by a slowseismic velocityzone that has been linked to the presence of 15–25% ofpartial meltsin the zone. The Aucanquilcha complex is much smaller volumetrically than the APVC ignimbrites, but the duration of activity and the location indicate that Aucanquilcha is a subcomponent of the APVC complex.[6]

The long-term magma output of Aucanquilcha is comparable to the magma output of other long-term active volcanoes in the central Andes such asOllagüeandLlullaillaco.In all such cases, an early peak in magma output is followed by later lower-volume activity (0.1 to 0.2 cubic kilometres per millennium (0.024 to 0.048 cubic miles per millennium), followed by 0.01 to 0.02 cubic kilometres per millennium (0.0024 to 0.0048 cubic miles per millennium)).Unzenin Japan andMount DuffandLassen PeakinCaliforniahave similar eruption histories. Such decreases may occur because of thelithostatic loadimposed by the edifices on themagma chambersand the increased travel distance of the magma through the edifice.[5]

Local setting

[edit]
Topographic map of the Chile-Bolivia frontier.
In this topographic map of the region, the white surface in the upper left is Aucanquilcha.

Aucanquilcha is part of a cluster of volcanoes located between theRio Loaand theChile–Boliviaborder.[7]Aucanquilcha sits on top of a 2.7–3.3myaandesiteplatform and rises more than 1,400 metres (4,600 ft) over it.[5]The main volcano is composed of an east-west 8-kilometre (5.0 mi) long chain ofstratovolcanoes[3]and has an estimated volume of 37 cubic kilometres (8.9 cu mi).[5]The maximum slope of the summit area is 25°.[8]During theCumbre Negra stage,apyroclastic flowoccurred on the northwestern side of the volcano. It covered 34 square kilometres (13 sq mi) on a run of 10 square kilometres (3.9 sq mi) and now has a volume of 0.3 cubic kilometres (0.072 cu mi). It was at first identified as adebris avalanche,but the lack of hummocky topography and the presence of large juvenile blocks identify it as a pyroclastic flow.[5]One block in the flow and thelava domefrom which the flow originated have been dated at 0.6 mya.[7]Lava flows, mostly from the summit areas, are dark to grey in colour and extend as far as 2–3 kilometres (1.2–1.9 mi) from theirvents.It is likely that two small lava domes (Cerro Cumbre Negra and Summit 5867) on the northwest flank occupyflank vents.[5]To the north lies the 3.3 mya old andesite Cerro Tres Monos ridge; to the west lies the east-west Cerro Polan and La Luna ridge.[5]

The volcanic cluster of which Aucanquilcha is a part contains about 19–20 volcanoes and has generated about 340 cubic kilometres (82 cu mi) of andesite anddaciteover eleven million years. Covering a surface area of 700 square kilometres (270 sq mi), the cluster is surrounded on its northern, western and eastern sides bysalt flatsandalluvial deposits.On its southern side lies theCerro Chelavolcano.[6][7]The cluster lies on a 70-kilometre (43 mi) thick crust,[6]and arid conditions since theMiocenehave preserved its structures. Its volcanoes are arranged in north-south and northwestern alignments, which may indicate a rupture of the crust above shallow magma reservoirs.[7]

Aucanquilcha underwent a northwestward flank collapse, generating a debris avalanche deposit. The debris avalanche descended 2,100 metres (6,900 ft) and ran for 17 kilometres (11 mi) with anazimuthof 211°, eventually covering an area of 59 square kilometres (23 sq mi). The flow was channeled betweenMiño Volcanoand Cerro Cumbre Negra (an eroded lava massif) towards the dryRio Loavalley, favouring the preservation of the slide deposit. The proximal parts of the slide are covered by younger eruptive products and also bymoraines,indicating that the slide was followed by at least oneglacial episode.The slide lacks the hummocky topography usually found on debris avalanches but has radial ridges and grooves.[8]Another landslide occurred during theRedondo stageon the eastern side of the main volcano into theSalar de Carcote.It has the classic hummocky topography of landslides and covers a length of 17 kilometres (11 mi) and a surface area of 35 square kilometres (14 sq mi), roughly half of the surface area of theMount St Helensavalanche of 1980 and one-third of the surface area of theOllagüeavalanche. A volume of 0.35 cubic kilometres (0.084 cu mi) is assumed based on a probable thickness of 10 metres (33 ft).[5][7]

Petrographically, the composition of the cluster ranges from andesite to dacite withSiO2ranging from 62.8% to 65.7%. Andesites appear as lava flows while dacites form lava domes and dome complexes.[3]The rocks from the main Aucanquilcha volcano are uniformlydaciticand show little evidence of temporal variation in their composition.[5]Potassiumcontent ranges from 1.5 to 4%.[9]Plagioclaseis the dominant component of the magma.Clinopyroxene+orthopyroxene+amphibole(hornblendeandpargasite) oramphibole+biotite+minor amounts ofpyroxeneare subordinate components.Apatite,ilmenite,magnetiteandzirconcan also be found. There is evidence of magma mixing and mingling.[5][6]

Rocks have aporphyritictexture.[5]Basaltic andesites typically contain less than 10% crystals while dacites generally have more than 20% crystals. The Alconcha group lavas of the first one million years are crystal-poor and lack biotite; later lavas contain biotite and more crystals. Based ongeothermometricdata, the highest temperatures occurred during phases of high activity and lower temperatures are associated with low output periods.[10]It is likely that crustal feedback and increased deep crustal influx of mantle-derivedbasaltsdrive increased magmatic flux. During the time of the Polan eruption on the west flank, magma output was spatially segregated with the peripheral Miño Volcano generating andesite lavas and the more central volcanos generating dacites.[7]

Various parts of the main volcano have been subjected tohydrothermal alteration.The Azufrera stage edifice was subject to the most alteration; especially in the summit area and between the Angulo and Azufrera summits liesulfurrichtalus deposits.[5]The central part of the complex is heavily altered byfumaroleactivity.[3]Hydrothermal alteration may be driven by the formation of a deep magma reservoir and resulting hydrothermal circulation in overlying rocks.[7]

Eruptive history

[edit]

Eruption rates increased 6 million years ago, coinciding with magmas becoming more uniform in composition and the onset of strong hydrothermal alteration. It is possible that solidification of magmas below the volcano insulated the feeding channels from heat loss and caused the temperatures in the system to increase. Activity waned again 2 million years ago, with magma and included crystals being drawn from depths of 3 to 23 kilometres (1.9 to 14.3 mi) and forming the Aucanquilcha volcano proper.[6][10]The 10-million-year duration of activity of theAltiplano–Puna volcanic complexsystems is comparable to the duration of Aucanquilcha activity.[11]The age of the lava flows ranges from heavily glaciated andesite flows overlying less-eroded ones to possibly postglacial lava flows that may be tens of thousands of years old.[3]

Aucanquilcha cluster

[edit]
Aucanquilca

The Aucanquilcha cluster formed in four stages, each corresponding to a group. The Alconcha group, with seven volcanoes, is constructed from pyroxene, andesite and dacite and formed 11–8 mya. It is constructed from two northerncomposite cones,Alconcha and Volcan Tuco (also known as Cerro Garage,dated10.96–10.51 mya), and five lava domes on the northeastern side of the cluster. Alconcha has a large breach on the southern side of itscraterthat is likely the product of a flank collapse but the avalanche deposit may be buried beneath younger material.Lavaswithin the breach are dated 10.78–10.43 mya. The centres of Volcan Tuco and Alconcha are heavily eroded, and Alconcha's lavas andscorialie on top of Tuco. The Ujinaignimbritewas erupted 9.4 mya from an unknown vent and has a volume of 2 cubic kilometres (0.48 cu mi) of dacite. While the vent location is unknown, the composition of the ignimbrite, and its dating and distribution, indicate an association with this group. The domes are poorly researched, with the Coscalito dome dated 8.9–8.7 mya and Cerro Amincha 8.01. The total volume of this group is 46 cubic kilometres (11 cu mi), indicating a flux rate of 0.013 cubic kilometres per millennium (0.0031 cubic miles per millennium).[7]

The Gordo group, which erupted 6–4 mya following a probable 2-million-year hiatus, is located in the southern and western parts of the cluster. Cerro Gordo itself (5.49mya) has a crater that is breached westwards, exposing about twelve radialdykesbut with no trace of a debris avalanche. One of the larger centres of the cluster, Gordo is associated with alava fieldon its western side that is dated 4.9 mya. Cerro Puquíos and Cerro Negro (5.81–5.28 mya) lie on the southern side of the cluster, and glacialcirquescutting their northeastern flanks reveal layers of scoria and lavas. Puquíos has an amphitheatre structure on its western side. Paco Paco (4.41–4.27 mya) is located north of most Gordo group volcanoes. It forms a 4 kilometres (2.5 mi) widestratoconewith a lava-filled crater, and layers of scoria and agglutinated lavas dip from it. Volcan Pabellón (4.14–4.12 mya) sits southwest of the Puquíos-Negro ridge. The Las Bolitas lava field (5.23–5.13 mya) is associated with the Gordo group but the vent locations are unknown. The total volume of this group is 55 cubic kilometres (13 cu mi), indicating a flux rate of 0.027 cubic kilometres per millennium (0.0065 cubic miles per millennium).[7]

The 3.6–2.3 mya Polan group, with ten dispersed volcanoes includingMiño Volcano,is the largest group in the cluster and includes Tres Monos, La Luna, Cerro Polan, Chaihuiri, Miño Volcano and the lavas of the Aucanquilcha platform. Cerro Polan's (3.5–3 mya) eastern side is deeplydissected,and the exposed materials are heavily altered in the deeper sections. Lava fields to Polan's west and southwest (2.6 mya on one western field) are associated with it. La Luna (2.97–2.57) lies just east of Polan; these two volcanoes were probably one volcano in the past. La Luna has a lava dome surrounded by aglaciatedbut unaltered lava table. Cerro Tres Monos (3.4–2.78 mya) forms a northbound 14-kilometre (8.7 mi) long ridge with at least six vents. Hydrothermal alteration has affected some lavas and pyroclastics from Tres Monos, and the western side has lateral and terminal moraines. The Aucanquilcha platform (3.6–2.7 mya) sits underneath the main Aucanquilcha volcano, and its lava mostly flowed north. Its southern side is a 4,500-metre (14,800 ft)tablewith one hill, Cerro Campana, dated to 3.3 mya. The platform presumably forms one third of the total volume of the Aucanquilcha cluster and may have originated from a part of the ridge of the La Luna-Polan trend, now buried beneath Aucanquilcha. Chaihuiri (2.39 mya) is a lava dome with moraines and two short lava flows; it is the youngest Polan group volcano. The total volume of this group is 154 cubic kilometres (37 cu mi), indicating a flux rate of 0.077 cubic kilometres per millennium (0.018 cubic miles per millennium).[7]

After the four main phases, somescoria conesofbasalticcomposition, including Poruñita and Luna de Tierra, formed between Aucanquilcha andOllagüe.[10]

Aucanquilcha proper

[edit]
Landscape view

The main Aucanquilcha volcano formed in four stages. Between 1.04–0.92myathe bulk of the volcano formed in theAzufrerastage. Onelava flowtoward the southwest is unusually long at 6 kilometres (3.7 mi). A vent at 6,116 metres (20,066 ft) altitude fed most of this edifice; a second vent on the northern flank at the 5,887 metres (19,314 ft) summit generated three lava flows, two shorter ones and a long one to the northwest. The Azufrera stage lavas areblockydacites with largeclastsand flow fronts up to 20 metres (66 ft) high. These flows are moderately altered and haveoxidationrinds. There is little evidence ofexplosiveactivity, but it may have been obscured byglacial erosion.The total volume is 21.1 cubic kilometres (5.1 cu mi), indicating a flux rate of 0.16 cubic kilometres per millennium (0.038 cubic miles per millennium). This volcano was probably an isolated cone, but the existence of a previous stage cannot be excluded.[5]

The second stage, namedRodado,lasted from 0.95 to 0.85 mya. It formed on the eastern slopes of the Azufrera volcano, with one vent at the 6,073 metres (19,925 ft) summit. Rodado stage lavas are blocky and platy and usually thicker than Azufrera stage lavas. Some of the summit vent lavas are among the mostvesicularof this stage. They are also lessweathered(oxidation rinds are c. 1 centimetre (0.39 in) thick) and less subject tosolfataricalteration. The Cerro Chinchillas lavas are the oldest of this stage; erupted from an unknown vent, they lackamphiboles.The total volume is 9.1 cubic kilometres (2.2 cu mi), indicating a flux rate of 0.09 cubic kilometres per millennium (0.022 cubic miles per millennium). A flank collapse, possibly triggered by a largeearthquake,occurred during this stage.[5]

The third stage is theCumbre Negrastage, named after the westernmost summit and principal vent of this stage, Cerro Cumbre Negra (5,670 metres (18,600 ft)). The time course of its activity is less defined than the previous two stages; it may have occurred between 1–0.47 mya, but most likely 0.6–0.5 mya based onpotassium–argon dating.Four lava flows derived from the main vent, all less than one kilometre long and 40–60 metres (130–200 ft) thicker than previous stages. They all have hydration rinds but no native sulfur deposits. This stage generated Aucanquilcha's only pyroclastic flow during a lava dome collapse as occurred onMerapiinIndonesia.The total volume of this stage is 0.7 cubic kilometres (0.17 cu mi), indicating a flux rate of 0.005 cubic kilometres per millennium (0.0012 cubic miles per millennium).[5]

The youngest stage, known asAngulo,lasted from 0.66 to 0.24 mya. It was centered between the Azufrera and Rodado stage edifices 0.35–0.23 mya. Most lava flows from this stage originate on a 1-kilometre (0.62 mi) long ridge that includes Aucanquilcha's highest summit. One crater on the northeast side of the ridge fed lavas to the north. Other than that, most flows extend southwards 4 to 9 kilometres (2.5 to 5.6 mi) from the vent, and with the exception of a due south flow 50 metres (160 ft) thick they are thin, with thicknesses of 15–20 metres (49–66 ft). One of the oldest flows has been compared in length to the 50% longerChao Daciteflow but is much thinner. The flows from this stage are weakly weathered and partially overlie glacial deposits. The total volume is 5.8 cubic kilometres (1.4 cu mi), indicating a flux rate of 0.015 cubic kilometres per millennium (0.0036 cubic miles per millennium).[5]

There is no evidence ofHoloceneactivity[12]but the volcano has active fumaroles though the low-temperature fumaroles are not visible through short wavelength infrared data from satellites.[13]Fumarole activity was observed in 1962[14]and is most conspicuous in the trenches dug during sulfur mining operations. Lava flow emissions and minorexplosive activity,confined to the edifice of the volcano, are the most important risks from renewed activity.[15]

Glaciation and hydrology

[edit]

The volcano is currently not glaciated despite its height, due to thearidityof the climate.[1]The Quebrada de Chaigüire valley originates at the foot of Aucanquilcha.[16]Some of the source springs of theRio Loaare on Aucanquilcha[17]and it drains the western and northwestern sides of the volcano; the eastern side drains into theSalar de Ollagüesalt pan,the northeastern into theSalar de Laguani,and the southeastern into theSalar de Carcote.Most valleys onlyintermittentlytransport water, if at all,[18]but it forms the headwaters of the Rio Loa.[19]

The volcanic cluster was modestly glaciated during theQuaternary,as evidenced byglacial striationsand moraines at elevations above 4,500 metres (14,800 ft),[7]and shows evidence of glaciers both on the main volcano and its subsidiaries. At least two distinct glacier stages took place.[19]The western Azufrera edifice was heavily glaciated in the past. At least three moraine stages have been mapped on that edifice, and on its southern side is found a modest cirque with glacially polished lavas on the floor. The Rodado stage edifice has several moraine stages on its southern slopes. Another small cirque with a moraine has been found in the northeastern side of the Cerro Cumbre Negra summit next to an Azufrera stage lava flow. A small moraine lies on the south side of the Angulo edifice; some lavas from that edifice overlie glacial deposits.[5]

Human activity and mining

[edit]
Tracks in a sulfur mine on Aucanquilcha
A sulfur mine on Aucanquilcha
Aucanquilcha camp

A famous[20]mine at 5,950 metres (19,520 ft) altitude[21]that yielded ore with 30% sulfur[22]was opened by Julian B. Carrasco in 1913, who subsequently established the Compañía Minera y Azufrera Carrasco S.A in 1933,[23]first at Ollagüe and after 1950 in Amincha.[24]The sulfur was transported down first withllamas,later through anaerial cablewaysystem from El Ángulo station to Amincha station and finally bytrucks.The sulfur was then transported toChuquicamatato be converted intosulfuric acid[20][25]or toAntofagastato be shipped.[20]The mine was active from 1950 to 1992.[26]In 1977 other sulfur mines were present to the west between Cerro Polan and Cerro Gordo and south of the main Aucanquilcha massif.[18]Amincha was closed in 1992;[27]the last reported mining activity on the mountain was in 1994[5]and during the 1980s[27]-1990s the worker camps were abandoned.[24]

The cableway, of which ruins are still standing,[20]runs from the mine to amining camp(5,300 metres (17,400 ft)) and from there to Amincha (3,900 metres (12,800 ft))[28]where the sulfur was refined during the 1950s.[20]The road leading up to the mine is dated 1972 and is now impassable because of rock falls.[28]There is still a relic network of roads leading up to 5,900 metres (19,400 ft)[5]as well as ruins of the Amincha and El Ángulo stations.[20]

Covelliteand othercopper sulfidesfound in the area appear to have formed through postvolcanicepithermalmineralization above deepporphyry copper mineralization.[29]The sulfur itself formed at temperatures of 450 °C (842 °F) in a now extinct fumarole.[30]

Altitude and habitation

[edit]

The sulfur mine is notable for being the highest mine in the world at 5,950 metres (19,520 ft)[28]and the highest permanently inhabited area.[8]An expedition in 1935, part of the International High Altitude Expedition, found that miners lived at an altitude of 5,300 metres (17,500 ft) in the town of Quilcha and reached the higher mine on foot. The expedition found that an even higher abandoned village at 5,639 metres (18,501 ft) existed, but miners refused to live there. The conclusion taken from the expedition was that 5,334 metres (17,500 ft) was the highest habitable altitude.[28]

West in 1986 reported that a few miners permanently lived in the mine area.[31]A small group of men, caretakers of the mine, has lived at an altitude of 5,900 metres (19,500 ft) in a galvanized iron hut. One of them reportedly had spent two years there.[32]These are considered to be the highest human inhabitants on Earth.[33]Research performed onAymaraminers of the Aucanquilcha mine indicates that they are fully acclimatized to the altitude, with lesshyperventilationand higherhemoglobinthan acclimatized people from lower areas.[34]Their families are born and raised at lower altitudes, however.[33]

See also

[edit]

References

[edit]
  1. ^abKull, Christoph; Grosjean, Martin (2000)."Late Pleistocene climate conditions in the north Chilean Andes drawn from a climate–glacier model".Journal of Glaciology.46(155): 622–632.Bibcode:2000JGlac..46..622K.doi:10.3189/172756500781832611.ISSN0022-1430.
  2. ^"Aucanquilcha".Andes Specialists.Retrieved2020-04-12.
  3. ^abcdeWörner, Gerhard; Moorbath, Stephen; Horn, Susanne; Entenmann, Jürgen; Harmon, Russel S.; Davidson, Jon P.;Lopez-Escobar, Leopoldo(1994). "Large- and Fine-Scale Geochemical Variations Along the Andean Arc of Northern Chile (17.5°– 22°S)".Tectonics of the Southern Central Andes:77–92.doi:10.1007/978-3-642-77353-2_5.ISBN978-3-642-77355-6.
  4. ^(in Spanish)Cerro Aucanquilcha
  5. ^abcdefghijklmnopqrstKlemetti, Erik W.;Grunder, Anita L.(2007). "Volcanic evolution of Volcán Aucanquilcha: a long-lived dacite volcano in the Central Andes of northern Chile".Bulletin of Volcanology.70(5): 633–650.Bibcode:2008BVol...70..633K.doi:10.1007/s00445-007-0158-x.ISSN0258-8900.S2CID140668081.
  6. ^abcdeWalker, B. A.;Grunder, A. L.;Wooden, J. L. (2010). "Organization and thermal maturation of long-lived arc systems: Evidence from zircons at the Aucanquilcha volcanic cluster, northern Chile".Geology.38(11): 1007–1010.Bibcode:2010Geo....38.1007W.doi:10.1130/G31226.1.ISSN0091-7613.
  7. ^abcdefghijkGrunder, Anita L.; Klemetti, Erik W.; Feeley, Todd C.; McKee, Claire M. (2008). "Eleven million years of arc volcanism at the Aucanquilcha Volcanic Cluster, northern Chilean Andes: implications for the life span and emplacement of plutons".Transactions of the Royal Society of Edinburgh: Earth Sciences.97(4): 415–436.doi:10.1017/S0263593300001541.ISSN0263-5933.S2CID129122958.
  8. ^abcFrancis, P. W.; Wells, G. L. (1988). "Landsat Thematic Mapper observations of debris avalanche deposits in the Central Andes".Bulletin of Volcanology.50(4): 258–278.Bibcode:1988BVol...50..258F.doi:10.1007/BF01047488.ISSN0258-8900.S2CID128824938.
  9. ^Gunn, B. M. (1974). "Systematic petrochemical differences in andesite suites".Bulletin Volcanologique.38(1): 481–490.Bibcode:1974BVol...38..481G.doi:10.1007/BF02599419.ISSN0258-8900.S2CID128974452.
  10. ^abcWalker, Barry A.; Klemetti, Erik W.;Grunder, Anita L.;Dilles, John H.; Tepley, Frank J.; Giles, Denise (2012). "Crystal reaming during the assembly, maturation, and waning of an eleven-million-year crustal magma cycle: thermobarometry of the Aucanquilcha Volcanic Cluster".Contributions to Mineralogy and Petrology.165(4): 663–682.Bibcode:2013CoMP..165..663W.doi:10.1007/s00410-012-0829-2.ISSN0010-7999.S2CID129808417.
  11. ^Salisbury, M. J.; Jicha, B. R.; de Silva, S. L.; Singer, B. S.; Jimenez, N. C.; Ort, M. H. (2010). "40Ar/39Ar chronostratigraphy of Altiplano-Puna volcanic complex ignimbrites reveals the development of a major magmatic province".Geological Society of America Bulletin.123(5–6): 821–840.Bibcode:2011GSAB..123..821S.doi:10.1130/B30280.1.ISSN0016-7606.
  12. ^Lara, L. E.; Flores, F.; Calderón, R.; Cardona, C. (1 January 2021)."Chapter 17 - Volcano hazards and risks in Chile".Forecasting and Planning for Volcanic Hazards, Risks, and Disasters.Elsevier. p. 620.ISBN978-0-12-818082-2.
  13. ^Rothery, D. A.; Francis, P. W.; Wood, C. A. (1988)."Volcano monitoring using short wavelength infrared data from satellites".Journal of Geophysical Research.93(B7): 7993.Bibcode:1988JGR....93.7993R.doi:10.1029/JB093iB07p07993.ISSN0148-0227.
  14. ^Zeil, Werner (1964). "Die Verbreitung des jungen Vulkanismus in der Hochkordillere Nordchiles".Geologische Rundschau.53(2): 731–757.Bibcode:1964GeoRu..53..731Z.doi:10.1007/BF02054561.ISSN0016-7835.S2CID128979648.
  15. ^Amigo, Álvaro R.; Bertin, Daniel U.; Orozco, Gabriel L. (2012).Peligros volcánicos de la Zona Norte de Chile(PDF)(Report). Carta geológica de Chile: Serie Geología Ambiental (in Spanish). Vol. 17.SERVICIO NACIONAL DE GEOLOGÍA Y MINERÍA.p. 14.ISSN0717-7305.Archived fromthe original(PDF)on June 29, 2021.Retrieved20 August2021.
  16. ^Villagrán, Carolina;Romo, Marcela; Castro, Victoria (2003)."ETNOBOTÁNICA DEL SUR DE LOS ANDES DE LA PRIMERA REGIÓN DE CHILE: UN ENLACE ENTRE LAS CULTURAS ALTIPLÁNICAS Y LAS DE QUEBRADAS ALTAS DEL LOA SUPERIOR".Chungará (Arica)(in Spanish).35(1).doi:10.4067/S0717-73562003000100005.ISSN0717-7356.
  17. ^Correa, Claudio (24 September 2021)."A solution to the enigma of the type locality of Telmatobiushalli Noble, 1938 (Anura, Telmatobiidae), a frog lost for 86 years".ZooKeys(1060): 183–192.doi:10.3897/zookeys.1060.67904.ISSN1313-2989.PMC8486727.PMID34690508.
  18. ^abDefense Mapping Agency Hydrographic/Topographic Center, Washington DC (1977).Cerro Araral; Chile; Bolivia(Map) (1 ed.). 1:250000. Joint Operations Graphic (in Spanish).Salar de Ascotan.Archived fromthe original(jpg)on 11 November 2010.Retrieved6 September2015.Alt URL
  19. ^abJenny, Bettina; Kammer, Klaus (1996).Climate Change in den trockenen Anden(in German). Verlag des Geographischen Institutes der Universität Bern. pp. 49–50.ISBN3906151034.
  20. ^abcdefRivera, Francisco (2 January 2020)."A Pendulum of Innovations and Challenges: Technological System and Industrial Heritage of Sulphur Mining in Northern Chile (1887–1993)".Industrial Archaeology Review.42(1): 48–61.doi:10.1080/03090728.2019.1709729.ISSN0309-0728.S2CID213428375.
  21. ^Wu, Tianyi (2001). "The Qinghai–Tibetan Plateau: How High Do Tibetans Live?".High Altitude Medicine & Biology.2(4): 489–499.doi:10.1089/152702901753397054.ISSN1527-0297.PMID11809089.
  22. ^Jon Erickson (2009).Environmental Geology: Facing the Challenges of Our Changing Earth.Infobase Publishing. pp. 242–243.ISBN978-1-4381-0963-3.
  23. ^González, José Antonio (2010)."The mining industry in Antofagasta and the Bolivian immigration during the nitrate cycle. Study notes".Revista Si Somos Americanos(in Spanish).10(2).
  24. ^abRivera, Francisco; González, Paula; Lorca, Rodrigo; Faundes, Wilfredo (2 January 2021)."Assessing the industrial past in the highlands of northern Chile".Journal of Community Archaeology & Heritage.8(1): 26–42.doi:10.1080/20518196.2020.1741119.ISSN2051-8196.S2CID216492401– viaResearchGate.
  25. ^Jason Wilson Professor of Latin American Literature University College London (4 August 2009).The Andes.Oxford University Press, USA. p. 198.ISBN978-0-19-973107-7.
  26. ^Nancy Yáñez Fuenzalida; Raúl Molina Otárola (2008).La gran minería y los derechos indígenas en el norte de Chile.LOM Ediciones.p. 63.ISBN978-956-00-0010-1.
  27. ^abGalaz-Mandakovic, Damir; Rivera, Francisco (15 March 2023). "Bolivian migration and ethnic subsidiarity in Chilean sulphur and borax high-altitude mining (1888–1946)".History and Anthropology.34(2): 234–259.doi:10.1080/02757206.2020.1862106.
  28. ^abcdWest, John B. (2002). "Highest Permanent Human Habitation".High Altitude Medicine & Biology.3(4): 401–407.doi:10.1089/15270290260512882.ISSN1527-0297.PMID12631426.
  29. ^Ferraris, F.; Vila, T. (1990). "Volcanic Sulfur Deposits in the Andes of Northern Chile".Stratabound Ore Deposits in the Andes:691–701.doi:10.1007/978-3-642-88282-1_55.ISBN978-3-642-88284-5.
  30. ^Dmitri Rouwet; Bruce Christenson; Franco Tassi; Jean Vandemeulebrouck (2 March 2015).Volcanic Lakes.Springer. pp. 159–161.ISBN978-3-642-36833-2.
  31. ^Noberto C. Gonzalez; M. Roger Fedde (6 December 2012).Oxygen Transfer from Atmosphere to Tissues.Springer Science & Business Media. pp. 10–11.ISBN978-1-4684-5481-9.
  32. ^West, J. B.(July 1987). "Alexander M. Kellas and the physiological challenge of Mt. Everest".Journal of Applied Physiology.63(1): 3–11.doi:10.1152/jappl.1987.63.1.3.PMID3305469.
  33. ^abGöran E. Nilsson (28 January 2010).Respiratory Physiology of Vertebrates: Life With and Without Oxygen.Cambridge University Press. p. 268.ISBN978-1-139-48535-7.
  34. ^Santolaya, R.B.; Lahiri, S.; Alfaro, R.T.; Schoene, R.B. (1989). "Respiratory adaptation in the highest inhabitants and highest Sherpa mountaineers".Respiration Physiology.77(2): 253–262.doi:10.1016/0034-5687(89)90011-X.ISSN0034-5687.PMID2506621.

Further reading

[edit]
Wikimedia Commons has media related toAucanquilcha.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Aucanquilcha&oldid=1194564254"