Lauca (volcano) explained
Lauca is a [1] high andesitic stratovolcano in the Central Volcanic Zone of the Andes on the Altiplano in northern Chile. Administratively it is located in Putre, Arica y Parinacota Region. The volcano was active during the Late Miocene from 10.5 million years ago onwards. A major ignimbrite collapsed the volcano in the Late Pliocene.
Geology
Andesites from the Lauca volcano, active in the Late Miocene as of 10.5 million years ago,[2] exist in two groups, plagioclase rich ones which underwent alteration and fine grained silicic ones that are fresher. The territory is underpinned with a crust formed from rocks of Precambrian to Cretaceous age, with thicknesses up to .[3] Amphibole rich lava flows formed a uniform volcanic cone. A later major ignimbrite eruption caused the collapse of the centre and formed the Lauca ignimbrite. A caldera is present, with a lava dome at the northeastern rim.
The Lauca ignimbrite has a thickness up to 150m (490feet), covering the El Diablo Formation in parts and filling the Lluta Canyon. Ar-Ar ages for this rhyolitic ignimbrite have been determined at 2.73 ± 0.02 Ma based on sanidine analysis and 2.87 ± 0.05 Ma from biotite.[4] The Lauca ignimbrite has been correlated to the Pérez ignimbrite in Bolivia and the Pachía ignimbrite in southern Peru.[5] Along the Copaquilla-Tignámar Fault, uplifting the eastern side over the western side,[6] the Lauca ignimbrite has been displaced over 100mto150mm (300feetto490feetm), indicative of tectonic activity after deposition in the Late Pliocene.[7] In parts, the Lauca ignimbrite is covered by conglomeratic terrace deposits.[8]
See also
References
Bibliography
- Charrier . Reynaldo . Hérail . Gérard . Pinto . Luisa . García . Marcelo . Riquelme . Ricardo . Farías . Marcelo . Muñoz . Nelson. Reynaldo Charrier . 2013 . Cenozoic tectonic evolution in the Central Andes in northern Chile and west central Bolivia: implications for paleogeographic, magmatic and mountain building evolution . . 102 . 1 . 235–264 . 10.1007/s00531-012-0801-4. 2013IJEaS.102..235C . 53365323 . none.
- García . Marcelo . Riquelme . Rodrigo . Farías . Marcelo . Hérail . Gérard . Charrier . Reynaldo . 2011 . Late Miocene–Holocene canyon incision in the western Altiplano, northern Chile: tectonic or climatic forcing? . Journal of the Geological Society, London . 168 . 4 . 1047–1060 . 10.1144/0016-76492010-134. 140203620 . none.
- Kött . A. . Gaupp . R. . Wörner . G. . December 1995 . Miocene to recent history of the western Altiplano in northern Chile revealed by lacustrine sediments of the Lauca basin (18°15'-18°40'S/69°30'-69°05'W) . . 84 . 4 . 770 . 10.1007/BF00240567 . 1995GeoRu..84..770K. 129479890 . none.
- Schlunegger . Fritz . Kober . Florian . Zeilinger . Gerold . Von Rotz . Ruedi . 2010 . Sedimentology-based reconstructions of paleoclimate changes in the Central Andes in response to the uplift of the Andes, Arica region between 19 and 21S latitude, northern Chile . . 99 . S123–S137 . 10.1007/s00531-010-0572-8 . 56390819 . none.
- Book: Wigger . edited by Klaus-Joachim Reutter, Ekkehard Scheuber, Peter J. . 2012 . Tectonics of the Southern Central Andes Structure and Evolution of an Active Continental Margin . Springer Berlin Heidelberg . Berlin, Heidelberg . 978-3-642-77353-2 . 1–334 . 21 March 2017. none.
- Wörner . Gerhardt . Leopoldo López Escobar . Lopez Escobar . Leopoldo . Moorbath . Stephen . Horn . Susan . Entenmann . Jürgen . Harmon . Russel S. . Davidson . Jon D. . 1992 . Variaciones geoquimicas, locales y regionales, en el frente volcanico cuaternario de los Andes centrales (17°30'-22°00'S), norte de Chile . . 19 . 1 . 21 March 2017 . es . live . https://web.archive.org/web/20170322111817/http://www.andeangeology.cl/index.php/revista1/article/view/1372 . 22 March 2017. none.
Notes and References
- Wigger et al., 2012, p.81
- Kött et al., 1995
- Wörner et al., 1992
- García et al., 2011, p.1053
- Charrier et al., 2013, p.245
- Charrier et al., 2013, p.255
- Charrier et al., 2013, p.247
- Schlunegger et al., 2010, p.S132
