Laguna Miscanti is a brackish waterlake located in the altiplano of the Antofagasta Region in northern Chile. Cerro Miñiques volcano and Cerro Miscanti tower over this lake. This 13.5 square kilometres (5.2sqmi) large heart-shaped lake has a deep blue colour and developed in a basin formed by a fault. South of Miscanti lies Laguna Miñiques, another lake which is separated from Miscanti by a lava flow that was emplaced there during the Pleistocene.
The lake is part of one of the seven sectors of Los Flamencos National Reserve. A number of birds and mammals live at the lake, which is a major tourist destination.
Laguna Miscanti has a surface area of 13.5 square kilometres (5.2sqmi)[b],[11] making it one of the largest waterbodies of the Atacama Altiplano.[12] The lake has the shape of an arrowhead with a peninsula jutting from the northern shore.[4] Maximum water depths reach 10 metres (33ft).[11] The western lakefloor is steep, while the eastern and southern shores have gentler slopes.[13] A lava flow separates the otherwise flat lake floor into two basins.[14] The surrounding terrain is covered by lake sediments, including calcarenite, diatomite, gravel and sand.[15] Former shorelines occur at distances approaching 1 kilometre (0.62mi) from the present-day lake shore.[13] A number of dry valleys - there are no no streams at Laguna Miscanti[16] - enter into Laguna Miscanti from the north, east and south[9] (Quebrada de Chaquisoqui[1]), and there are two springs in the bays on either side of the peninsula.[4]
The waters are clear[13] and brackish[c],[11] with only weak currents if at all.[13] The lake has no surface outflow. Presently, water seeps to Miñiques through a lava flow[11] along the path of the Quebrada Nacimiento fault,[17] and possibly to Salar de Atacama;[18] the removal of salts through this outflow prevents Miscanti from becoming a salt pan.[17] Most water, however, leaves Laguna Miscanti through evaporation,[19] making it a closed basin.[17]
1.5 kilometres (0.93mi) south of[24] the lake is another waterbody, Laguna Miñiques.[25] The barrier separating the two probably formed during the Pleistocene, when a lava flow erupted from Cerro Miñiques split the lake basin in two.[20][26] West of the lake is the Chuculaqui[4] or Miscanti Ridge.[27]
Laguna Miscanti
Palaeolake
In the past, Laguna Miscanti was much larger, covering an area of 38.2 square kilometres (14.7sqmi). Its water levels were about 29 metres (95ft) higher than today, reaching an altitude of 4,179 metres (13,711ft),[13] and may have merged with Laguna Miñiques.[17] The lake submerged alluvial fans[28] and left beach terraces,[11] lacustrine sediments[g][19] and wavecut platforms.[17] There was more biological activity in the lake during the highstand:[30] Algal bioherms[31] and stromatolithes grew in the water,[17] and fossils indicate the presence of Botryococcus, Pediastrum integrum and Ranunculus plants.[32] During former lake highstands a lake chain[33] or a combined lake overflowed into the Pampa Varela basin[11] south-southwest of Miñiques.[34]
Geology and geomorphology
The catchment of the lake consists mainly of volcanic and sedimentary rocks ranging from Miocene to Holocene age and covers a surface area of 320 square kilometres (120sqmi).[11]Quaternary volcanoes with summit elevations of 5,000–6,000 metres (16,000–20,000ft) dot the catchment.[6] Among these are Cerro Miscanti (5,622 metres (18,445ft)) and Cerro Miñiques (5,910 metres (19,390ft)) northeast and south of the lake, respectively.[34] The volcanoes are part of the Andean Volcanic Belt, which is formed by the subduction of the Nazca Plate under the South American Plate.[28]
Laguna Lejia,[19] Miscanti, Miñiques occupy basins formed by tectonic activity,[24][11][19] specifically of the 100 kilometres (62mi) long[35] Quebrada Nacimiento[17] or Miscanti fault[36] west of Laguna Miscanti,[27] one of the most important faults in the region.[37] Its reactivation during[19] the Pliocene and Pleistocene formed the basins[17] and the Miscanti Ridge.[27][26]
There are no long-running weather records from Laguna Miscanti.[42] Temperatures are cold, with average annual temperatures of 2°C (36°F), varying by about 8–10°C (46–50°F) between seasons.[43] Parts of the lake surface freeze over during winter.[11] The lake area is usually a little warmer than the surrounding region.[44]
Laguna Miscanti may have formed 22,000 years ago, when tectonic and volcanic activity trapped water in the future lake basin. At this point, the lake reached its highstand for the first time. About 18,000 years ago,[13] the Last Glacial Maximum turned drier[48] and colder, leading to a total disappearance of vegetation[49] and a drying of the lake between 22,000 and 14,000 years ago.[50]
In the late Pleistocene and early Holocene the climate of the Atacama and Central Andes was much wetter (Central Andean Pluvial Event[51] or "Tauca phase"[12]) and precipitation nearly doubled in the southern Atacama.[52] As a consequence, lakes formed (Lake Tauca) or grew in size,[53] including Laguna Miscanti where the second highstand occurred[13] during the Late Glacial.[19] This humid period has been subdivided into two stages,[25] the wetter[54] Tauca or CAPE I (17,500–14,200 years before present) and Coipasa or CAPE II (13,800–9,700 years before present), which are not entirely synchronous between the Atacama and the Altiplano.[25][51]Pollen data indicate that a stronger easterly wind was responsible for the highstand at Miscanti.[48]
The Holocene brought a more stable,[55] warmer and drier climate to the central and south-central Andes which causes the lakes to dry up. Miscanti became hypersaline[52] as water levels dropped by about 10 metres (33ft).[56] It may have dried up completely, forming a bog[13] or mudflat surrounded by wetlands that attracted camelids[13] like guanacos and vicuñas.[57] The dry period was caused by decreased insolation caused by the Milankovich cycles weakening the monsoon.[58][59] A widespread abandonment of archaeological sites, the "archaeological silence", coincides with the drought although Miscanti itself remained inhabited during that time.[24] The exact chronology of the dry period depends on the site.[24]
At Miscanti there were wet pulses on century or decade time scales,[13] and a brief moist epoch between 6,500 and 5,000 years ago.[60] At Miscanti, the dry period definitively ended after about 4,000 years ago[61] through several pulses of moisture,[62] and human resettlement at Laguna Miscanti took place about 3,400 years ago.[63] The lake reformed 3,600 years ago and has remained since.[13] More recent fluctuations include a dry period between 1650–1850 AD[i], perhaps linked to the ending Little Ice Age.[65]
The town of Peine draws its water supply from the Miscanti basin.[81] The inhabitants of Socaire used the area for grazing, and it bears spiritual and religious importance for them.[82] Laguna Miscanti and Laguna Miñiques are part of the third sector of the Los Flamencos National Reserve,[83] and are jointly administered by the community of Socaire and by the National Forest Corporation.[84] In 2002, there were 5,000 tourists at Miscanti and the nearby lake Miñiques,[85] and in 2015, one in three tourists who went to the Los Flamencos National Reserve visited Miscanti and Laguna Miñiques.[86] Laguna Miscanti is of scientific importance, as it has a record of palaeoclimatic changes going back to the last glacial maximum.[13]
An archeological site ("Miscanti-1")[52] has been discovered on a beach terrace at the southeastern end of the lake. It contains remnants of animals, hearths and lithic artifacts buried in volcanic ash.[13] It was presumably a campsite used by prehistoric hunter-gatherer populations,[87] which produced hunting tools and consumed game there.[88]
Climate variability influenced human settlement in the region during the Holocene, which took place mainly during wetter periods[65] when the environment became much more favourable[m],[52] becoming concentrated in several environmentally favourable spaces during dry periods.[24] At Laguna Miscanti, wetlands and areas suitable for grazing formed during the middle Holocene drought, thus the area remained hospitable for human inhabitation.[24]
↑Servicio Nacional de Turismo (Chile) (23 March 2018). Ruta del Desierto (Report) (in Spanish). p.14. Archived from the original(PDF) on 7 October 2021. Retrieved 7 October 2021.
12Chong-Diaz, G. (1984). "Die Salare in Nordchile-Geologie, Struktur und Geochemie¢journal=Geotektonische Forschungen" (in German). 67: 62–63.{{cite journal}}: Cite journal requires |journal= (help)
↑Aron, F. A.; Gonzalez, G.; Cembrano, J. M.; Veloso, E. E. (December 2010). Reverse Faulting as a Crucial Mechanism for Magma Ascent in Compressional Volcanic Arcs: Field Examples from the Central Andes. American Geophysical Union, Fall Meeting 2010. Bibcode:2010AGUFM.V43B2379A. V43B-2379.
↑Keller, Tobias; Tornos, Fernando; Hanchar, John M.; Pietruszka, Dorota K.; Soldati, Arianna; Dingwell, Donald B.; Suckale, Jenny (17 October 2022). "Genetic model of the El Laco magnetite-apatite deposits by extrusion of iron-rich melt". Nature Communications. 13 (1): 2. doi:10.1038/s41467-022-33302-z.
↑Romero, Hugo; Kampf, Stephanie (2003). "Impacts of Climate Fluctuations and Climate Changes on the Sustainable Development of the Arid Norte Grande in Chile". Climate and Water. Advances in Global Change Research. Vol.16. Springer, Dordrecht. p.94. doi:10.1007/978-94-015-1250-3_5. ISBN978-90-481-6386-1.
↑Ríos-Escalante, Patricio De los; Morrone, Juan J.; Rivera, Reinaldo (1 January 2013). "A checklist of Hyalella (Amphipoda) from Chile". Crustaceana. 86 (12): 1429. doi:10.1163/15685403-00003256. ISSN1568-5403.
↑Valenzuela, América; Chiappe, Carlos (26 September 2024). "Política estatal en territorio indígena: Los negocios étnicos turísticos (NET) en San Pedro de Atacama, Norte de Chile". The Journal of Latin American and Caribbean Anthropology: 9. doi:10.1111/jlca.12742.
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