Lake Escara

Lake Escara is a former lake in the southern Altiplano.[1]

The Lake Escara lake episode was first defined in 1978, along with Lake Minchin and Lake Tauca. Today the Altiplano hosts Lake Titicaca in the north and Lake Poopo, Salar de Coipasa and Salar de Uyuni in the south.[2] Escara was identified in the central Altiplano,[3] it may be the oldest Altiplano lake cycle.[4]

The lake was probably sizable, perhaps reaching the size of Lake Tauca and Ouki.[5] Lake levels reached an altitude of 3,780 metres (12,400 ft).[6] At the town of Escara, 8 metres (26 ft) thick deposits have been left by the lake.[7]

It is dated to 191,000 years BP.[8] This date is of a tuff associated with lake deposits, the deposits themselves have not been dated.[1] This tuff was found in the L5 sediment unit of Salar de Uyuni which has been linked to Escara.[9] Some tuffs found in Escara lake deposits have been dated to about 1.87 million years ago.[5] During the episode of Lake Escara, Lake Ballivian may have existed in the northern Altiplano;[6] Lake Escara would be thus identical to "lake pre-Minchin" which has left terraces 60–70 metres (200–230 ft) above the present-day elevation.[10]

References
  1. Placzek et al. 2009, p. 27.
  2. ROUCHY, JEAN MARIE; SERVANT, MICHEL; FOURNIER, MARC; CAUSSE, CHRISTIANE (December 1996). "Extensive carbonate algal bioherms in upper Pleistocene saline lakes of the central Altiplano of Bolivia". Sedimentology. 43 (6): 975. doi:10.1111/j.1365-3091.1996.tb01514.x.
  3. Fornari, Risacher & Féraud 2001, p. 270.
  4. Placzek et al. 2009, p. 34.
  5. Placzek et al. 2009, p. 32.
  6. Lavenu, Alain (1992-01-01). "Origins". In Dejoux, C.; Iltis, A. (eds.). Lake Titicaca. Monographiae Biologicae. 68. Springer Netherlands. p. 9. doi:10.1007/978-94-011-2406-5_1. ISBN 9789401050616.
  7. Placzek et al. 2009, p. 30.
  8. Collado, Gonzalo A.; Vila, Irma; Méndez, Marco A. (November 2011). "Monophyly, candidate species and vicariance in Biomphalaria snails (Mollusca: Planorbidae) from the Southern Andean Altiplano". Zoologica Scripta. 40 (6): 620. doi:10.1111/j.1463-6409.2011.00491.x.
  9. Fornari, Risacher & Féraud 2001, p. 279.
  10. Ahlfeld, Federico (1972). Geología de Bolivia (in Spanish). Editorial Los Amigos del Libro. p. 158.

Sources
  • Fornari, Michel; Risacher, François; Féraud, Gilbert (August 2001). "Dating of paleolakes in the central Altiplano of Bolivia". Palaeogeography, Palaeoclimatology, Palaeoecology. 172 (3–4): 269–282. doi:10.1016/S0031-0182(01)00301-7.CS1 maint: ref=harv (link)
  • Placzek, Christa; Quade, Jay; Rech, Jason A.; Patchett, P.J.; Pérez de Arce, Carlos (February 2009). "Geochemistry, chronology and stratigraphy of Neogene tuffs of the Central Andean region". Quaternary Geochronology. 4 (1): 22–36. doi:10.1016/j.quageo.2008.06.002.CS1 maint: ref=harv (link)

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