DOCSLIB.ORG

Lascar Volcano, Chile

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Lascar Volcano, Chile Edinburgh Research Explorer Post-depositional fracturing and subsidence of pumice flow deposits: Lascar Volcano, Chile Citation for published version: Whelley, PL, Jay, J, Calder, ES, Pritchard, ME, Cassidy, NJ, Alcaraz, S & Pavez, A 2012, 'Post-depositional fracturing and subsidence of pumice flow deposits: Lascar Volcano, Chile', Bulletin of Volcanology, vol. 74, no. 2, pp. 511-531. https://doi.org/10.1007/s00445-011-0545-1 Digital Object Identifier (DOI): 10.1007/s00445-011-0545-1 Link: Link to publication record in Edinburgh Research Explorer Document Version: Publisher's PDF, also known as Version of record Published In: Bulletin of Volcanology Publisher Rights Statement: This is an Open-Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly cited. General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 08. Oct. 2021 Bull Volcanol (2012) 74:511–531 DOI 10.1007/s00445-011-0545-1 RESEARCH ARTICLE Post-depositional fracturing and subsidence of pumice flow deposits: Lascar Volcano, Chile Patrick L. Whelley & J. Jay & E. S. Calder & M. E. Pritchard & N. J. Cassidy & S. Alcaraz & A. Pavez Received: 11 September 2010 /Accepted: 22 August 2011 /Published online: 27 September 2011 # Springer-Verlag 2011 Abstract Unconsolidated pyroclastic flow deposits of the radar interferometry shows that deposit subsidence of up to 1993 eruption of Lascar Volcano, Chile, have, with time, 1 cm/year occurred between 1993 and 1996 with continued become increasingly dissected by a network of deeply subsidence occurring at a slower rate thereafter. In situ penetrating fractures. The fracture network comprises measurements show that 1 m below the surface, the 1993 orthogonal sets of decimeter-wide linear voids that form a deposits remain 5°C to 15°C hotter, 18 years after pseudo-polygonal grid visible on the deposit surface. In this emplacement, than adjacent deposits. Based on the observed work, we combine shallow surface geophysical imaging subsidence as well as estimated cooling rates, the fractures are tools with remote sensing observations and direct field inferred to be the combined result of deaeration, thermal measurements of the deposit to investigate these fractures contraction, and sedimentary compaction in the months to and their underlying causal mechanisms. Based on ground years following deposition. Significant environmental factors, penetrating radar images, the fractures are observed to have including regional earthquakes in 1995 and 2007, accelerated propagated to depths of up to 10 m. In addition, orbiting settling at punctuated moments in time. The spatially variable fracture pattern relates to surface slope and lithofacies Editorial responsibility: B. van Wyk de Vries variations as well as substrate lithology. Similar fractures Electronic supplementary material The online version of this article have been reported in other ignimbrites but are generally (doi:10.1007/s00445-011-0545-1) contains supplementary material, exposed only in cross section and are often attributed to which is available to authorized users. formation by external forces. Here we suggest that such P. L. Whelley (*) : E. S. Calder interpretations should be invoked with caution, and deforma- Department of Geology, University at Buffalo, tion including post-emplacement subsidence and fracturing of State University of New York, loosely packed ash-rich deposits in the months to years post- 411 Cooke Hall, emplacement is a process inherent in the settling of pyroclastic Buffalo, NY 14260-3050, USA e-mail: [email protected] material. : J. Jay M. E. Pritchard Keywords Lascar . Ignimbrite . InSAR . Ground penetrating Department of Earth as Atmospheric Sciences, Cornell University, radar . Compaction . Deaeration . Cooling Ithaca, NY, USA N. J. Cassidy School of Physical and Geographical Sciences, Keele University, Introduction Keele, UK S. Alcaraz We document a network of fractures, which are progres- Department of Earth Sciences, The Open University, sively dissecting the 18–20 April 1993 pumice flow Milton Keynes MK7 6AA, UK deposits at Lascar Volcano, Chile (Fig. 1). The fractures are manifest at the surface as elongate irregular trenches, A. Pavez Departamento de Geofísica, Universidad de Chile, which cut through unconsolidated ignimbrite. They repre- Santiago, Chile sent the first stages of post-depositional deformation of 512 Bull Volcanol (2012) 74:511–531 Fig. 1 a The location of Lascar Volcano in northern Chile. b a b Active vent View of Lascar from an over- Lascar looking cliff to the north showing the northwest fan of 1993 deposits. c Individual pyroclastic flow units on break- out fans I and II, mapped on a portion of GEOTEC image 14602-04. Relative stratigraphic positions were deduced by field observations Breakout fan I Breakout fan II 200 m c 13 4 14 Fan I 6 3 13 14 5 11 12 2 Lava Flow 11 10 1 5 12 1 7 9 9 3 8 Relative age 7 8 2 6 Fan II 10 5 6 6 5 S 4 2 3 4 4 3 1 2 Relative age 1 100 m ignimbrite in an arid environment. Their presence at Lascar continuum must exist between deaeration and the longer- provides an opportunity to map their distribution, monitor term effects of compaction involving reduction of void space their development, and constrain the timescales over which and grain reorientation, but this has never been specifically their formative processes operate. This work furthers the investigated. Field observations of easily fluidized fresh understanding of how pyroclastic materials behave and are deposits are common (Rowley et al. 1981; Wilson and Head modified by, or respond to, environmental factors in the 1981; Torres et al. 1996; Branney and Kokelaar 2002;P. decades after emplacement. Cole, personal communication, 1997) and indicate that at the Post-depositional deformation of pyroclastic deposits natural scale, deaeration must continue over longer time occurs over a range of spatial and temporal scales (Table 1). periods (days to weeks) than can be reproduced in the Internally driven processes, such as deaeration, cooling, laboratory (e.g., Druitt et al. 2004, 2007). initial compaction, and the onset of welding, are dependent External forces drive additional processes which may on the eruptive conditions and material properties, including affect those already mentioned: Seismic ground accelera- grain size and composition. These processes begin to occur tion can induce fracturing (e.g., Nocita 1988; Brown and during and immediately after emplacement, but the timescales Branney 2004), circulating fluids or volatiles can cement or over which they extend are not well constrained. The deposits indurate unconsolidated deposits (e.g., Zies 1924; Bacon studied here are non-welded and largely unconsolidated, so 2008; Calder et al. 2000), and mass wasting and fluvial or welding, which is extensively covered elsewhere (e.g., Ross eolian erosion modify the aspect of the deposits. Mass and Smith 1961; Wolff and Wright 1981;Sparksetal.1999), wasting and fluvial erosion can also induce secondary flow is not considered here. Recent laboratory experiments on phenomena including deposit-derived pyroclastic flows fluidized natural samples (e.g., Druitt et al. 2004, 2007) (Torres et al. 1996), debris flows, and hyper-concentrated found that deaeration reduced deposit thickness by 50%, in lahars (e.g., Pierson et al. 1992; Branney and Gilbert 1995; the minutes after emplacement. In natural systems, a Major et al. 1996). The deposit-derived pyroclastic flows at Bull Volcanol (2012) 74:511–531 513 Table 1 Post-depositional processes affecting ignimbrites Process Time scale Features/effects Example Reference Internal Deaeration Minutes to years Density increase Mt. St. Helens, Wilson and Head 1981; (lithological) laboratory experiments Rowley et al. 1981;Druittetal. 2004, 2007 Welding Minutes to days Eutaxitic fabric, Bishop Tuff, Murga Ross and Smith 1961; fiamme, joints Caldera Ignimbrites Sparks et al. 1999 Rheomorphism Minutes to hours Flow lineations, deposit Borrowdale Volcanic Schmincke and Swanson to days thickness variations, Group, TL Ignimbrite 1967; Sumner and eutaxitic fabric Branney 2002; Branney et al. 2004 Compaction Weeks to decades Fracture network, Grants Ridge Tuff, Keating and Valentine subsidence Lascar 1998; this work pumice flow deposit Cooling Years Joints Bishop Tuff Sheridan 1970 Indurationa Decades to millions Hardening, fumarolic Valley of 10,000 Smokes; Griggs 1922; Sheridan of years incrustations, mounds Bishop Tuff; Akdag- 1970; Schumacher and and ridges Zelve Ignimbrite; Mues-Schumacher 1997; Mazama-Crater Bacon 2008 Lake External Aeolian erosion Days to millions Yardangs, pits Tara Ignimbrite Bailey et al. 2007 (environmental) of years Fluvial erosion Days to decades Gullies, channels Atana Ignimbrite Bailey et al. 2007 Mass wasting Days to millennia
Load more

Recommended publications
  • Full-Text PDF (Final Published Version)
    Pritchard, M. E., de Silva, S. L., Michelfelder, G., Zandt, G., McNutt, S. R., Gottsmann, J., West, M. E., Blundy, J., Christensen, D. H., Finnegan, N. J., Minaya, E., Sparks, R. S. J., Sunagua, M., Unsworth, M. J., Alvizuri, C., Comeau, M. J., del Potro, R., Díaz, D., Diez, M., ... Ward, K. M. (2018). Synthesis: PLUTONS: Investigating the relationship between pluton growth and volcanism in the Central Andes. Geosphere, 14(3), 954-982. https://doi.org/10.1130/GES01578.1 Publisher's PDF, also known as Version of record License (if available): CC BY-NC Link to published version (if available): 10.1130/GES01578.1 Link to publication record in Explore Bristol Research PDF-document This is the final published version of the article (version of record). It first appeared online via Geo Science World at https://doi.org/10.1130/GES01578.1 . Please refer to any applicable terms of use of the publisher. University of Bristol - Explore Bristol Research General rights This document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/red/research-policy/pure/user-guides/ebr-terms/ Research Paper THEMED ISSUE: PLUTONS: Investigating the Relationship between Pluton Growth and Volcanism in the Central Andes GEOSPHERE Synthesis: PLUTONS: Investigating the relationship between pluton growth and volcanism in the Central Andes GEOSPHERE; v. 14, no. 3 M.E. Pritchard1,2, S.L. de Silva3, G. Michelfelder4, G. Zandt5, S.R. McNutt6, J. Gottsmann2, M.E. West7, J. Blundy2, D.H.
    [Show full text]
  • Compositional Zoning of the Bishop Tuff
    JOURNAL OF PETROLOGY VOLUME 48 NUMBER 5 PAGES 951^999 2007 doi:10.1093/petrology/egm007 Compositional Zoning of the Bishop Tuff WES HILDRETH1* AND COLIN J. N. WILSON2 1US GEOLOGICAL SURVEY, MS-910, MENLO PARK, CA 94025, USA 2SCHOOL OF GEOGRAPHY, GEOLOGY AND ENVIRONMENTAL SCIENCE, UNIVERSITY OF AUCKLAND, PB 92019 AUCKLAND MAIL CENTRE, AUCKLAND 1142, NEW ZEALAND Downloaded from https://academic.oup.com/petrology/article/48/5/951/1472295 by guest on 29 September 2021 RECEIVED JANUARY 7, 2006; ACCEPTED FEBRUARY 13, 2007 ADVANCE ACCESS PUBLICATION MARCH 29, 2007 Compositional data for 4400 pumice clasts, organized according to and the roofward decline in liquidus temperature of the zoned melt, eruptive sequence, crystal content, and texture, provide new perspec- prevented significant crystallization against the roof, consistent with tives on eruption and pre-eruptive evolution of the4600 km3 of zoned dominance of crystal-poor magma early in the eruption and lack of rhyolitic magma ejected as the BishopTuff during formation of Long any roof-rind fragments among the Bishop ejecta, before or after onset Valley caldera. Proportions and compositions of different pumice of caldera collapse. A model of secular incremental zoning is types are given for each ignimbrite package and for the intercalated advanced wherein numerous batches of crystal-poor melt were plinian pumice-fall layers that erupted synchronously. Although released from a mush zone (many kilometers thick) that floored the withdrawal of the zoned magma was less systematic than previously accumulating rhyolitic melt-rich body. Each batch rose to its own realized, the overall sequence displays trends toward greater propor- appropriate level in the melt-buoyancy gradient, which was self- tions of less evolved pumice, more crystals (0Á5^24 wt %), and sustaining against wholesale convective re-homogenization, while higher FeTi-oxide temperatures (714^8188C).
    [Show full text]
  • GY 111: Physical Geology
    UNIVERSITY OF SOUTH ALABAMA GY 111: Physical Geology Lecture 9: Extrusive Igneous Rocks Instructor: Dr. Douglas W. Haywick Last Time 1) The chemical composition of the crust 2) Crystallization of molten rock 3) Bowen's Reaction Series Web notes 8 Chemical Composition of the Crust Element Wt% % of atoms Oxygen 46.6 60.5 Silicon 27.7 20.5 Aluminum 8.1 6.2 Iron 5.0 1.9 Calcium 3.6 1.9 Sodium 2.8 2.5 Potassium 2.6 1.8 Magnesium 2.1 1.4 All other elements 1.5 3.3 Crystallization of Magma http://myweb.cwpost.liu.edu/vdivener/notes/igneous.htm Bowen’s Reaction Series Source http://www.ltcconline.net/julian Igneous Rock Composition Source: http://hyperphysics.phy-astr.gsu.edu Composition Formation Dominant Silica content Temperature Minerals Ultramafic Very high Olivine, pyroxene Very low (<45%) Mafic High Olivine, pyroxene, low Ca-plagioclase Intermediate Medium Na-Plagioclase, moderate amphibole, biotite Felsic Medium-low Orthoclase, quartz, high (>65%) muscovite, biotite Igneous Rock Texture Extrusive Rocks (Rapid Cooling; non visible* crystals) Intrusive Rocks (slow cooling; 100 % visible crystals) *with a hand lens Igneous Rock Texture Igneous Rock Texture Today’s Agenda 1) Pyro-what? (air fall volcanic rocks) 2) Felsic and Intermediate Extrusive Rocks 3) Mafic Extrusive Rocks Web notes 9 Pyroclastic Igneous Rocks Pyroclastic Igneous Rocks Pyroclastic: Pyro means “fire”. Clastic means particles; both are of Greek origin. Pyroclastic Igneous Rocks Pyroclastic: Pyro means “fire”. Clastic means particles; both are of Greek origin. Pyroclastic rocks are usually erupted from composite volcanoes (e.g., they are produced via explosive eruptions from viscous, “cool” lavas) Pyroclastic Igneous Rocks Pyroclastic: Pyro means “fire”.
    [Show full text]
  • Receiver Function Analyses of Uturuncu Volcano, Bolivia and Vicinity
    University of South Florida Scholar Commons School of Geosciences Faculty and Staff Publications School of Geosciences 11-2017 Receiver Function Analyses of Uturuncu Volcano, Bolivia and Vicinity Heather McFarlin University of South Florida Douglas Christensen University of Alaska, Fairbanks Stephen R. McNutt University of South Florida, [email protected] Kevin M. Ward University of Utah Jamie Ryan University of Arizona See next page for additional authors Follow this and additional works at: https://scholarcommons.usf.edu/geo_facpub Part of the Earth Sciences Commons Scholar Commons Citation McFarlin, Heather; Christensen, Douglas; McNutt, Stephen R.; Ward, Kevin M.; Ryan, Jamie; Zandt, George; and Thompson, Glenn, "Receiver Function Analyses of Uturuncu Volcano, Bolivia and Vicinity" (2017). School of Geosciences Faculty and Staff Publications. 1430. https://scholarcommons.usf.edu/geo_facpub/1430 This Article is brought to you for free and open access by the School of Geosciences at Scholar Commons. It has been accepted for inclusion in School of Geosciences Faculty and Staff Publications by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Authors Heather McFarlin, Douglas Christensen, Stephen R. McNutt, Kevin M. Ward, Jamie Ryan, George Zandt, and Glenn Thompson This article is available at Scholar Commons: https://scholarcommons.usf.edu/geo_facpub/1430 Research Paper THEMED ISSUE: PLUTONS: Investigating the Relationship between Pluton Growth and Volcanism in the Central Andes GEOSPHERE Receiver function analyses of Uturuncu volcano, Bolivia and vicinity Heather McFarlin1, Douglas Christensen2, Stephen R. McNutt1, Kevin M. Ward3, Jamie Ryan4, George Zandt4, and Glenn Thompson1 1University of South Florida School of Geosciences, 4202 E. Fowler Avenue, NES 107, Tampa, Florida 33620, USA GEOSPHERE; v.
    [Show full text]
  • 00-P. P.Ginas + Editorial
    Estudios Atacameños Nº 16 - 1998 La tradición surandina del desierto: Etnobotánica del área del Salar de Atacama (Provincia de El Loa, Región de Antofagasta, Chile)1 CAROLINA VILLAGRÁN*, VICTORIA CASTRO**, GILBERTO SÁNCHEZ***, MARCELA ROMO**, CLAUDIO LATORRE** y LUIS FELIPE HINOJOSA** RESUMEN El área del Salar de Atacama, Provincia de El Loa, to de las plantas en los territorios de estas culturas segunda Región de Antofagasta del norte de Chi- y definir sus singularidades etnobotánicas, en co- le, es una de las más secas del mundo, correspon- rrespondencia con su situación tan especial den- diendo al área de máxima penetración del Desier- tro de los Andes del norte de Chile. Con este pro- to de Atacama en la costa Pacífica de Sudamérica. pósito, se realizó una recolección exhaustiva de la En efecto, y en concordancia con la disminución flora del área y un muestreo sistemático de la ve- de las lluvias en sentido NW-SE, desde los Andes getación, este último siguiendo un transecto de Arica (18°S), hacia los de Antofagasta (24°S), altitudinal desde el Salar de Atacama (2.700 m) se observa que la vegetación se retrae paulatina- hasta el Salar de Aguas Calientes (4.500 m). Pos- mente hacia mayores altitudes. Así, extensas áreas teriormente, se entrevistaron 38 personas prove- al interior de la ciudad de Calama, representadas nientes de San Pedro de Atacama, Toconao, por el Salar de Atacama, Cordillera de Domeyko Talabre, Camar, Socaire y Peine. y sectores bajos de la vertiente occidental andina corresponden a desiertos ‘absolutos’, con valores Para las 173 especies de plantas consultadas se de coberturas de plantas vasculares prácticamen- registraron 416 nombres vernaculares, correspon- te nulos.
    [Show full text]
  • Mineralogical and Geochemical Indicators of Subaerial Weathering in the Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy)
    Georgia State University ScholarWorks @ Georgia State University Geosciences Theses Department of Geosciences 4-27-2010 Mineralogical and Geochemical Indicators of Subaerial Weathering in the Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy) Jennifer M. Dickie Georgia State University Follow this and additional works at: https://scholarworks.gsu.edu/geosciences_theses Part of the Geography Commons, and the Geology Commons Recommended Citation Dickie, Jennifer M., "Mineralogical and Geochemical Indicators of Subaerial Weathering in the Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy)." Thesis, Georgia State University, 2010. https://scholarworks.gsu.edu/geosciences_theses/23 This Thesis is brought to you for free and open access by the Department of Geosciences at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Geosciences Theses by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. MINERALOGICAL AND GEOCHEMICAL INDICATORS OF SUBAERIAL WEATHERING IN THE POZZOLANE ROSSE IGNIMBRITE (ALBAN HILLS VOLCANIC DISTRICT, ITALY) by JENNIFER M. DICKIE Under the direction of Dr. Daniel Deocampo ABSTRACT The Pozzolane Rosse ignimbrite [PR] (457±4 ka) in the Alban Hills Volcanic District, Rome, Italy was exposed ~ 40 ka prior to a subsequent volcanic event which coverd it entirely. XRF, XRD, and clay separation results from PR samples from INGV and CA1 boreholes and Castel di Leva quarry show evidence of paleopedogenesis. All locations display loss of base cations, loss of K is consistent with XRD datat showing dissolution or alteration of leucite to analcime. Accumulation of Al and high L.O.I. support XRD evidence of 1:1 clay species at upper depth.
    [Show full text]
  • Erosion, Transport and Segregation of Pumice and Lithic Clasts in Pyroclastic ¯Ows Inferred from Ignimbrite at Lascar Volcano, Chile
    Journal of Volcanology and Geothermal Research 104 (2000) 201±235 www.elsevier.nl/locate/jvolgeores Erosion, transport and segregation of pumice and lithic clasts in pyroclastic ¯ows inferred from ignimbrite at Lascar Volcano, Chile E.S. Caldera,*, R.S.J. Sparksa, M.C. Gardewegb aDepartment of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK bServicio Nacional de Geologia y Mineria, Avenida Santa Maria 0104, Casilla 10465, Santiago, Chile Received 4 November 1998; revised and accepted 4 May 2000 Abstract Investigations have been made on the distribution of pumice and lithic clasts in the lithic rich Soncor ignimbrite (26.5 ka) and the 1993 pumice ¯ow deposits of Lascar Volcano, Chile. The Soncor ignimbrite shows three main lithofacies which grade into one another. Coarse lithic breccias range from matrix poor strati®ed varieties, irregular shaped sheets and elongate hummocks in proximal environments, to breccia lenses with pumiceous ignimbrite matrix. Massive, lithic rich facies comprise the bulk of the ignimbrite. Pumice rich facies are bimodal with abundant large pumice clasts (often with reverse grading), rare lithic clasts and occur distally and on high ground adjacent to deep proximal valleys. In the 1993 pyroclastic ¯ow deposits lithic rich facies are deposited on slopes up to 148 whereas pumice rich facies are deposited only on slopes ,48. Lithic rich parts show a thin pumice rich corrugated surface which can be traced into the pumice rich facies. The high lithic content in the Soncor ignimbrite is attributed to the destruction of a pre-existing dome complex, deep explosive cratering into the interior of the volcano and erosion during pyroclastic ¯ow emplacement.
    [Show full text]
  • Final Geología Del Volcán Parinacota.Indd 2 24-10-2012 10:36:57 CONTENIDO
    28356 TAPA PARINACOTA.pdf 1 05-11-12 15:28 ISSN 0717-7283 S U B D I R E C C I Ó N N A C I O N A L D E G E O L O G Í A SITUACIÓN DE CARTAS VECINAS 70º45' 30' 15' 45' VILLA COSA INDUSTRIAL PILLA 18º00' CERRO GEOLOGÍA DEL VOLCÁN PARINACOTA PUTRE VOLCÁN LARANCAGUA PARINACOTA 15' REGIÓN DE ARICA Y PARINACOTA (Versión corregida) TERRITORIO CHILENO Jorge Clavero R. ANTÁRTICO 90° 53° R. Steve J. Sparks Edmundo Polanco V. CARTA GEOLÓGICA DE CHILE POLO SUR SERIE GEOLOGÍA BÁSICA No. 132 Escala 1:50.000 "ACUERDO ENTRE LA REPÚBLICA DE CHILE Y LA REPÚBLICA ARGENTINA PARA PRECISAR EL RECORRIDO DEL LÍMITE DESDE EL MONTE FITZ ROY 2012 HASTA EL CERRO DAUDET". (Buenos Aires, 16 de diciembre de 1998). 28356 TAPA PARINACOTA.pdf 2 05-11-12 15:28 CARTA GEOLÓGICA DE CHILE SERIE GEOLOGÍA BÁSICA No. 110 Geología del Área Queule-Toltén, Regiones de La Araucanía y de Los Ríos. 2008. D. Quiroz y P. Duhart. Texto y 1 mapa escala 1:100.000. No. 111 Geología del Área Carrizal Bajo-Chacritas, Región de Atacama. 2008. C. Arévalo y D. Welkner. Texto y 1 mapa escala 1:100.000. No. 112 Geología del Área de Chile Chico-Río de Las Nieves, Región Aisén del General Carlos Ibáñez del Campo. 2008. R. de la Cruz y M. Suárez. Texto y 1 mapa escala 1:100.000. No. 113 Geología de las ciudades de Iquique y Alto Hospicio, Región de Tarapacá. 2008. C. Marquardt, N.
    [Show full text]
  • Geological Framework of the Mineral Deposits of the Collahuasi District
    413 Collahuasi Mineral District / References REFERENCES CITED Aceñolaza, F. G., and Toselli, A. J., 1976, Consideraciones estratigráficas y tectónicas sobre el Paleozoico inferior del noroeste Argentino: 2º Congreso Latinoamericano de la Geología, p. 755-764. Aeolus-Lee, C.-T., Brandon, A. D. and Norman, M. D., 2003, Vanadium in peridotites as a proxy for paleo-fO2 during partial melting: prospects, limitations, and implications. Geochimica et Cosmochimica Acta 67, 3045–3064. Aeolus-Lee, C.-T., Leeman, W. P., Canil, D., and Xheng-Xue, A. L., 2005, Similar V/Sc Systematics in MORB and Arc Basalts: Implications for the Oxygen Fugacities of their Mantle Source Regions: Journal of Petrology, v. 46, p. 2313-2336. Allen, S. R., and McPhie, J., 2003, Phenocryst fragments in rhyolitic lavas and lava domes: Journal of Volcanology and Geothermal Research, v. 126, p. 263-283. Allmendinger, R. W., Jordan, T. E., Kay, S. M., and Isacks, B. L., 1997, The evolution of the Altiplano-Puna Plateau of the Central Andes: Annual Review of Earth and Planetary Sciences, v. 25, p. 139-174 Allmendinger, R. W., Gonzalez, G., Yu, J., and Isacks, B. L., 2003, The East-West fault scarps of northern Chile: tectonic significance and climatic clues: Actas - 10º Congreso Geológico Chileno, Concepción, 2003. Alonso-Perez, R., Müntener, O., and Ulmer, P., 2009, Igneous garnet and amphibole fractionation in the roots of island arcs: experimental constraints on andesitic liquids: Contributions to Mineralpgy and Petrology, v. 157, p. 541–558. Alpers, C. N., and Brimhall, G. H., 1988, Middle Miocene climatic change in the Atacama Desert, northern Chile; evidence from supergene mineralization at La Escondida; with Suppl.
    [Show full text]
  • Servicio Nacional De Turismo
    SERVICIO NACIONAL DE TURISMO ATRACTIVOS TURISTICOS 2012 CODIGO ATRACTIVO REGION DE ANTOFAGASTA R02001 NOMBRE DEL ATRACTIVO REGION VALLE DE QUILLAGUA REGIÓN DE ANTOFAGASTA JERARQUIA PROVINCIA TOCOPILLA NACIONAL CATEGORIA DIRECCION SITIO NATURAL COMUNA MARIA ELENA TIPO DE ATRACTIVO MONTAÑA LOCALIDAD O SECTOR VALLE DE QUILLAGUA TIPO DE PROPIEDAD SUBTIPO DEL ATRACTIVO ESTACIONALIDAD DE USO PÚBLICA VALLE O QUEBRADA TODO EL AÑO ADMINISTRACION PÚBLICA DOTACION SERVICIOS BASICOS LOCALIDAD URBANA MAS CERCANA AGUA POTABLE, ELECTRICIDAD QUILLAGUA DEMANDA TURISTICA LOCAL, REGIONAL, NACIONAL TELEFONO INFORMACION DISTANCIA CAPITAL REGIONAL 314 (55) 557708 EN KMS CAPITAL COMUNAL 94 USO TURISTICO ACTUAL ESTADO DE CONSERVACION BUENA DESCRIPCION GENERAL Las pequeñas haciendas del valle de Quillagua, llamadas por los naturales "CERCOS", producen únicamente alfalfa. Pero se cosecha en gran cantidad, el fruto de los algarrobos que allí abundan; los que producen cerca de 400 kilogramos de fruto, cada cosecha. En el valle, hay 26 "cercos" que producen alfalfa, la cual da hasta cinco cortes en el año. Propuesto como Sitio prioritario para la Conservación de la Biodiversidad (Estrategia Nacional de Biodiversidad). SERVICIO NACIONAL DE TURISMO ATRACTIVOS TURISTICOS 2012 CODIGO ATRACTIVO REGION DE ANTOFAGASTA R02005 NOMBRE DEL ATRACTIVO REGION OASIS ALBERTO TERRAZAS (EX POZO 3) REGIÓN DE ANTOFAGASTA JERARQUIA PROVINCIA EL LOA REGIONAL CATEGORIA DIRECCION CENTRO O LUGAR DE ESPARCIMIENTO COMUNA SAN PEDRO DE ATACAMA TIPO DE ATRACTIVO PARQUE DE RECREACIÓN LOCALIDAD
    [Show full text]
  • MMA Memo 251
    MMA Memo 251 MMA Site East of San Pedro De Atacama North Chile Volcanic Hazards Assessment and Geologic Setting Moyra C. Gardeweg P. Consultant Geologist August 1996 Fig. 1 - Location of map of the MMA site. Access roads, villages, and well known volcanic centers are shown. The stippled zone shows the area comprised by the simplified geologic map of Fig. 2. Fig 2. - Simplified geological map of the site area over a 1:500.000 scale satellite image. Based on Marinovic and Lahsen (1984) and Ramfrez and Gardeweg (1982). Fig. 3. - Satellite image of the MMA site (white arrow). Shown are the Chascón dome (ch), Chajnantor dome (cj) and Purico complex (p). The Cajón ignimbrite (ci) extends radially from the Purico complex and is covered by the lavas of the volcanoes Licancabur (l), Guayaques (g), and Santa Bárbara (sb). The north end of the La Pacana caldera resurgent dome (prd), source of the Atana Ignimbrite, is also observed as are the salty lakes of Laguna Verde (lv) in Bolivia. Fig. 4. - Chascón dome and the Agua Amarga creek, immediately east of the MMA site. View northward; in rear the Chajnantor dome, Juriques and Licancabur volcanoes and a NS linear group of volcanoes in the border with Bolivia. 9 Fig 5. - Distribution of volcanic vents (active, potentially active and extint) and calderas in the study and surrounding areas. Contours to depth of the scenter of the Wadati-Benioff zone and the Peéu-Chile trench are shown Currently Putana is in a solfataric stage, with extensive fumarolic activity observed from the end of the 19th century that persists to the present day.
    [Show full text]
  • A Re-Appraisal of the Stratigraphy and Volcanology of the Cerro Galán Volcanic System, NW Argentina
    Bull Volcanol (2011) 73:1427–1454 DOI 10.1007/s00445-011-0459-y RESEARCH ARTICLE A re-appraisal of the stratigraphy and volcanology of the Cerro Galán volcanic system, NW Argentina Chris B. Folkes & Heather M. Wright & Raymond A. F. Cas & Shanaka L. de Silva & Chiara Lesti & Jose G. Viramonte Received: 15 February 2009 /Accepted: 31 January 2011 /Published online: 6 May 2011 # Springer-Verlag 2011 Abstract From detailed fieldwork and biotite 40Ar/39Ar the Toconquis Group (the Pitas and Vega Ignimbrites). dating correlated with paleomagnetic analyses of lithic clasts, Toconquis Group Ignimbrites (~5.60–4.51 Ma biotite ages) we present a revision of the stratigraphy, areal extent and have been discovered to the southwest and north of the volume estimates of ignimbrites in the Cerro Galán volcanic caldera, increasing their spatial extents from previous complex. We find evidence for nine distinct outflow estimates. Previously thought to be contemporaneous, we ignimbrites, including two newly identified ignimbrites in distinguish the Real Grande Ignimbrite (4.68±0.07 Ma biotite age) from the Cueva Negra Ignimbrite (3.77± Editorial responsibility: K. Cashman 0.08 Ma biotite age). The form and collapse processes of This paper constitutes part of a special issue: the Cerro Galán caldera are also reassessed. Based on re- interpretation of the margins of the caldera, we find evidence Cas RAF, Cashman K (eds) The Cerro Galan Ignimbrite and Caldera: for a fault-bounded trapdoor collapse hinged along a regional characteristics and origins of a very large volume ignimbrite and its N-S fault on the eastern side of the caldera and accommo- magma system.
    [Show full text]