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Rapid Magma Ascent and Generation of Th Excesses in the Lower Crust At
Earth and Planetary Science Letters 255 (2007) 229–242 www.elsevier.com/locate/epsl Rapid magma ascent and generation of 230Th excesses in the lower crust at Puyehue–Cordón Caulle, Southern Volcanic Zone, Chile ⁎ Brian R. Jicha a, , Brad S. Singer a, Brian L. Beard a, Clark M. Johnson a, Hugo Moreno-Roa b,c, José Antonio Naranjo b a Department of Geology and Geophysics, University of Wisconsin—Madison, 1215 West Dayton Street, Madison WI 53706, USA b Servicio Nacional de Geología y Minería (SERNAGEOMIN), Avenida Santa María, 0104 Santiago, Chile c Observatorio Volcanologico de los Andes del Sur (OVDAS), Cerro Ñielol-Sector Antenas, Temuco, Chile Received 28 July 2006; received in revised form 7 December 2006; accepted 8 December 2006 Available online 30 January 2007 Editor: R.W. Carlson Abstract Basaltic to rhyolitic lavas and tephras erupted over the last 70 kyr at the Puyehue–Cordón Caulle volcanic complex in the Andean Southern Volcanic Zone (SVZ) were analyzed for major and trace element, Sr isotope, and U–Th isotope compositions to constrain the timescales of magmatic processes and identify the subducted and crustal components involved in magma genesis. Internal U–Th mineral isochrons from five lavas and three tephra fall deposits are indistinguishable from their eruption ages, indicating a short period (b1000 yr) of crystal residence in the magma prior to eruption. The (230Th/232Th) ratios define a narrow range (0.80–0.83) compared to that of all SVZ lavas (0.72–0.97), suggesting that Puyehue basalt was derived from a relatively uniform mantle source. Dacites and rhyolites have the largest U excesses and likely evolved via fractional crystallization of a plagioclase-dominated mineral assemblage. -
Counterclockwise Rotation of Late Eocene – Oligocene Forearc Deposits in Southern Peru and Its Significance for Oroclinal Bend
Counterclockwise rotation of Late Eocene – Oligocene forearc deposits in southern Peru and its significance for oroclinal bending in the Central Andes Pierrick Roperch, Thierry Sempere, Orlando Macedo, César Arriagada, Michel Fornari, Claudio Tapia, Marcelo Garcia, Carlo Laj To cite this version: Pierrick Roperch, Thierry Sempere, Orlando Macedo, César Arriagada, Michel Fornari, et al.. Coun- terclockwise rotation of Late Eocene – Oligocene forearc deposits in southern Peru and its significance for oroclinal bending in the Central Andes. Tectonics, American Geophysical Union (AGU), 2006, 25 (3), pp.TC3010. 10.1029/2005TC001882. insu-00261209 HAL Id: insu-00261209 https://hal-insu.archives-ouvertes.fr/insu-00261209 Submitted on 29 Jun 2016 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. TECTONICS, VOL. 25, TC3010, doi:10.1029/2005TC001882, 2006 Counterclockwise rotation of late Eocene–Oligocene fore-arc deposits in southern Peru and its significance for oroclinal bending in the central Andes Pierrick Roperch,1,2 Thierry Sempere,3 Orlando Macedo,4 Ce´sar Arriagada,2 Michel Fornari,5 Claudio Tapia,2 Marcelo Garcı´a,6 and Carlo Laj7 Received 6 July 2005; revised 20 February 2006; accepted 14 March 2006; published 1 June 2006. -
The Volcanic Ash Soils of Chile
' I EXPANDED PROGRAM OF TECHNICAL ASSISTANCE No. 2017 Report to the Government of CHILE THE VOLCANIC ASH SOILS OF CHILE FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS ROMEM965 -"'^ .Y--~ - -V^^-.. -r~ ' y Report No. 2017 Report CHT/TE/LA Scanned from original by ISRIC - World Soil Information, as ICSU World Data Centre for Soils. The purpose is to make a safe depository for endangered documents and to make the accrued information available for consultation, following Fair Use Guidelines. Every effort is taken to respect Copyright of the materials within the archives where the identification of the Copyright holder is clear and, where feasible, to contact the originators. For questions please contact [email protected] indicating the item reference number concerned. REPORT TO THE GOVERNMENT OP CHILE on THE VOLCANIC ASH SOILS OP CHILE Charles A. Wright POOL ANL AGRICULTURE ORGANIZATION OP THE UNITEL NATIONS ROME, 1965 266I7/C 51 iß - iii - TABLE OP CONTENTS Page INTRODUCTION 1 ACKNOWLEDGEMENTS 1 RECOMMENDATIONS 1 BACKGROUND INFORMATION 3 The nature and composition of volcanic landscapes 3 Vbloanio ash as a soil forming parent material 5 The distribution of voloanic ash soils in Chile 7 Nomenclature used in this report 11 A. ANDOSOLS OF CHILE» GENERAL CHARACTERISTICS, FORMATIVE ENVIRONMENT, AND MAIN KINDS OF SOIL 11 1. TRUMAO SOILS 11 General characteristics 11 The formative environment 13 ÈS (i) Climate 13 (ii) Topography 13 (iii) Parent materials 13 (iv) Natural plant cover 14 (o) The main kinds of trumao soils ' 14 2. NADI SOILS 16 General characteristics 16 The formative environment 16 tö (i) Climat* 16 (ii) Topograph? and parent materials 17 (iii) Natural plant cover 18 B. -
Lesson Plans Villarrica Volcano Eruption
My NASA Data - Lesson Plans Villarrica Volcano Eruption Purpose Students use scale to determine the area of volcanic deposits following the March 3, 2015 eruption of Chile's Mount Villarrica stratovolcano, one of the country's most active volcanoes. Learning Objectives Students use a scale to calculate a map area. Students determine the area of volcanic deposits. Students explain the time scale involved in the measured change. Why Does NASA Study This Phenomenon? Landsat 8 Launched on February 11, 2013, Landsat 8 (formerly the Landsat Data Continuity Mission, LDCM) is the most recently launched Landsat satellite. It is collecting valuable data and imagery used in 1 / 8 agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth’s surface on a global basis. The data from Landsat spacecraft constitute the longest record of the Earth’s continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Essential Questions How quickly did volcanic debris from Mount Villarricia's eruption cover the area? How much of thea area was covered? Materials Required Rulers Colored printouts of images Technology Requirements Standalone Lesson (no technology required) Teacher Background Information Glacier-clad Villarrica is one of Chile's most active volcanoes. It rises above the lake and town of the same name. It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andean chain. A 6-km-wide caldera formed during the late Pleistocene. A 2-km-wide caldera that formed about 3500 years ago is located at the base of the presently active, dominantly basaltic to basaltic-andesitic cone at the NW margin of the Pleistocene caldera. -
Late Mesozoic to Paleogene Stratigraphy of the Salar De Atacama Basin, Antofagasta, Northern Chile: Implications for the Tectonic Evolution of the Central Andes
Late Mesozoic to Paleogene stratigraphy of the Salar de Atacama Basin, Antofagasta, Northern Chile: Implications for the tectonic evolution of the Central Andes Constantino Mpodozisa,T,Ce´sar Arriagadab, Matilde Bassoc, Pierrick Roperchd, Peter Cobbolde, Martin Reichf aServicio Nacional de Geologı´a y Minerı´a, now at Sipetrol. SA, Santiago, Chile bDepartamento de Geologı´a, Universidad de Chile, Santiago, Chile cServicio Nacional de Geologı´a y Minerı´a, Santiago, Chile dIRD/Dep. de Geologı´a, Universidad de Chile, Santiago, Chile eGe´osciences-Rennes (UMR6118 du CNRS), France fDepartment of Geological Sciences University of Michigan, United States Abstract The Salar de Atacama basin, the largest bpre-AndeanQ basin in Northern Chile, was formed in the early Late Cretaceous as a consequence of the tectonic closure and inversion of the Jurassic–Early Cretaceous Tarapaca´ back arc basin. Inversion led to uplift of the Cordillera de Domeyko (CD), a thick-skinned basement range bounded by a system of reverse faults and blind thrusts with alternating vergence along strike. The almost 6000-m-thick, upper Cretaceous to lower Paleocene sequences (Purilactis Group) infilling the Salar de Atacama basin reflects rapid local subsidence to the east of the CD. Its oldest outcropping unit (Tonel Formation) comprises more than 1000 m of continental red sandstones and evaporites, which began to accumulate as syntectonic growth strata during the initial stages of CD uplift. Tonel strata are capped by almost 3000 m of sandstones and conglomerates of western provenance, representing the sedimentary response to renewed pulses of tectonic shortening, which were deposited in alluvial fan, fluvial and eolian settings together with minor lacustrine mudstone (Purilactis Formation). -
La Catástrofe Del Nevado Del Ruiz, ¿Una Enseñanza Para El Ecuador? El Caso Del Cotopaxi
La catástrofe del Nevado del Ruiz, ¿Una enseñanza para el Ecuador? El caso del Cotopaxi. Robert d’Ercole To cite this version: Robert d’Ercole. La catástrofe del Nevado del Ruiz, ¿Una enseñanza para el Ecuador? El caso del Cotopaxi.. Estudios de Geograf’ia, Corporación Editora Nacional, 1989, Riesgos Naturales en Quito, 2, pp.5-32. hal-01184809 HAL Id: hal-01184809 https://hal.archives-ouvertes.fr/hal-01184809 Submitted on 25 Aug 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. LA CATASTROFE DEL NEVADO DEL RUIZ l UNA ENSENANZA- PARA EL ECUADOR ? EL CASO DEL COTOPAXI Robert D'Ercole* El 13 de noviembre de 1985, el volcân colombiano, el Nevado deI Ruiz, erupciono provocando la muerte de unas 25.000 personas. Esta es la mayor catâstrofe causada por un volcan desde la que produjo 29.000 victimas, en 1902 en la isla Martinica, luego de la erupci6n de la Montafla Pelée. La magnitud de las consecuencias y el hecho de que el Ruiz haya dado signos de reactivaci6n mucho tiempo antes, plantean el problema deI fenomeno natural pero también de los factores humanos que originaron la tragedia. -
Field Measurements of Active Volcanoes in the Southern Chilean Andes
Field Measurements of Active Volcanoes in the Southern Chilean Andes February – March 2012 Kelby Hicks Kayla Iacovino Tehnuka Ilanko Yves Moussallam Nial Peters Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK _____________________________________________________________________ Funding provided by the Royal Geopgraphical Society with IBG facilitated a month- long volcano monitoring campaign on three active volcanoes in Chile: Villarrica, a steadily active and constantly degassing stratovolcano; Puyehue-Cordon Caulle, a recently active, explosive volcano; and Lascar, a periodically active volcano in the Atacama region, which showed signs of unrest prior to this field campaign. This funding combined with additional monies from Antofagasta, The Jeremy Willson Charitable Trust and the Cambridge University Department of Geography was used principally for equipment costs, transportation, and guide hire at the fieldwork sites. From February 1st to March 6th 2012 our group of five PhD students, through collaboration with the local volcanic observatory OVDAS (Observatorio Volcanologico de los Andes del Sur), deployed a series of remote and direct sensing instruments previously unavailable to local observatory at Villarrica, Puyehue-Cordon Caulle, and Láscar, three active volcanoes that present a real and significant risk to surrounding populations. Here we present an overview of the work conducted and preliminary high-resolution data on the volcanic emissions at these three sites, an essential component of volcanic hazard assessment and eruption forecasting. _____________________________________________________________________ Cover Image: The team sets up equipment near the active vent of Puyehue-Cordon Caulle. Fieldwork Overview After a few days spent organising logistics in Santiago the team headed south to Temuco where we had scheduled a meeting with the head of OVDAS. -
30564 NMA 23 Degrees South
chapter 6 Claudio Latorre, Julio L Betancourt, Jason A Rech, Jay Quade, Camille Holmgren, Christa Placzek, Antonio JC Maldonado, Mathias Vuille and Kate Rylander Late Quaternary history of the Atacama Desert Of the major subtropical deserts found in the Southern Hemisphere, the Atacama Desert is the driest. Throughout the Quaternary, the most pervasive climatic infl uence on the desert has been millennial-scale changes in the frequency and seasonality of the scant rainfall, and associated shifts in plant and animal distributions with elevation along the eastern margin of the desert. Over the past six years, we have mapped modern vegetation gradients and developed a number of palaeoenvironmental records, including vegetation histories from fossil rodent middens, groundwater levels from wetland (spring) deposits, and lake levels from shoreline evidence, along a 1200-kilometre transect (16–26°S) in the Atacama Desert. A strength of this palaeoclimate transect has been the ability to apply the same methodologies across broad elevational, latitudinal, climatic, vegetation and hydrological gradients. We are using this transect to reconstruct the histories of key components of the South American tropical (summer) and extratropical (winter) rainfall belts, precisely at those elevations where average annual rainfall wanes to zero. The focus has been on the transition from sparse, shrubby vegetation (known as the prepuna) into absolute desert, an expansive hyperarid terrain that extends from just above the coastal fog zone (approximately 800 metres) to more than 3500 metres in the most arid sectors in the southern Atacama. Our study focuses on rodent middens (cf. Betancourt et al. 1990). These are amalgamations of plant remains (including seeds, fl owers, leaves and wood), bones, insects, feathers and rodent faeces, glued together within a crystallised matrix of rodent urine. -
Area Changes of Glaciers on Active Volcanoes in Latin America Between 1986 and 2015 Observed from Multi-Temporal Satellite Imagery
Journal of Glaciology (2019), 65(252) 542–556 doi: 10.1017/jog.2019.30 © The Author(s) 2019. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons. org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. Area changes of glaciers on active volcanoes in Latin America between 1986 and 2015 observed from multi-temporal satellite imagery JOHANNES REINTHALER,1,2 FRANK PAUL,1 HUGO DELGADO GRANADOS,3 ANDRÉS RIVERA,2,4 CHRISTIAN HUGGEL1 1Department of Geography, University of Zurich, Zurich, Switzerland 2Centro de Estudios Científicos, Valdivia, Chile 3Instituto de Geofisica, Universidad Nacional Autónoma de México, Mexico City, Mexico 4Departamento de Geografía, Universidad de Chile, Chile Correspondence: Johannes Reinthaler <[email protected]> ABSTRACT. Glaciers on active volcanoes are subject to changes in both climate fluctuations and vol- canic activity. Whereas many studies analysed changes on individual volcanoes, this study presents for the first time a comparison of glacier changes on active volcanoes on a continental scale. Glacier areas were mapped for 59 volcanoes across Latin America around 1986, 1999 and 2015 using a semi- automated band ratio method combined with manual editing using satellite images from Landsat 4/5/ 7/8 and Sentinel-2. Area changes were compared with the Smithsonian volcano database to analyse pos- sible glacier–volcano interactions. Over the full period, the mapped area changed from 1399.3 ± 80 km2 − to 1016.1 ± 34 km2 (−383.2 km2)or−27.4% (−0.92% a 1) in relative terms. -
Crustal Faults in the Chilean Andes: Geological Constraints and Seismic Potential
Andean Geology 46 (1): 32-65. January, 2019 Andean Geology doi: 10.5027/andgeoV46n1-3067 www.andeangeology.cl Crustal faults in the Chilean Andes: geological constraints and seismic potential *Isabel Santibáñez1, José Cembrano2, Tiaren García-Pérez1, Carlos Costa3, Gonzalo Yáñez2, Carlos Marquardt4, Gloria Arancibia2, Gabriel González5 1 Programa de Doctorado en Ciencias de la Ingeniería, Pontificia Universidad Católica de Chile, Avda. Vicuña Mackenna 4860, Macul, Santiago, Chile. [email protected]; [email protected] 2 Departamento de Ingeniería Estructural y Geotécnica, Pontificia Universidad Católica de Chile, Avda. Vicuña Mackenna 4860, Macul, Santiago, Chile. [email protected]; [email protected]; [email protected] 3 Departamento de Geología, Universidad de San Luis, Ejercito de Los Andes 950, D5700HHW San Luis, Argentina. [email protected] 4 Departamento de Ingeniería Estructural y Geotécnica y Departamento de Ingeniería de Minería, Pontificia Universidad Católica de Chile. Avda. Vicuña Mackenna 4860, Macul, Santiago, Chile. [email protected] 5 Departamento de Ciencias Geológicas, Universidad Católica del Norte, Angamos 0610, Antofagasta, Chile. [email protected] * Corresponding author: [email protected] ABSTRACT. The Chilean Andes, as a characteristic tectonic and geomorphological region, is a perfect location to unravel the geologic nature of seismic hazards. The Chilean segment of the Nazca-South American subduction zone has experienced mega-earthquakes with Moment Magnitudes (Mw) >8.5 (e.g., Mw 9.5 Valdivia, 1960; Mw 8.8 Maule, 2010) and many large earthquakes with Mw >7.5, both with recurrence times of tens to hundreds of years. By contrast, crustal faults within the overriding South American plate commonly have longer recurrence times (thousands of years) and are known to produce earthquakes with maximum Mw of 7.0 to 7.5. -
In-Stream Wetland Deposits, Megadroughts, and Cultural Change in the Northern Atacama Desert, Chile
Quaternary Research (2019), 91,63–80. THEMATIC SET Copyright © University of Washington. Published by Cambridge University Press, 2019. doi:10.1017/qua.2018.122 DRYLANDS In-stream wetland deposits, megadroughts, and cultural change in the northern Atacama Desert, Chile Craig D. Tullya, Jason A. Recha*, T. Race Workmana, Calogero M. Santorob, José M. Caprilesc, Eugenia M. Gayod,e, Claudio Latorref,g aDepartment of Geology and Environmental Earth Science,Miami University, Oxford, Ohio 45056, USA bInstituto de Alta Investigación, Universidad de Tarapacá, Antofagasta 1520, Arica 00236, Chile cDepartment of Anthropology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA dDepartamento de Oceanografia, Universidad de Concepción, Concepción 4070386, Chile eCenter for Climate Change and Resilience Research (CR2), Santiago 8370415, Chile fCentro UC del Desierto de Atacama & Departamento de Ecología, Pontificia Universidad Católica de Chile, Alameda 340, Santiago 6513677, Chile gInstitute of Ecology & Biodiversity (IEB), Casilla 653, Santiago 6513677, Chile (RECEIVED November 18, 2017; ACCEPTED September 24, 2018) Abstract A key concern regarding current and future climate change is the possibility of sustained droughts that can have profound impacts on societies. As such, multiple paleoclimatic proxies are needed to identify megadroughts, the synoptic climatology responsible for these droughts, and their impacts on past and future societies. In the hyperarid Atacama Desert of northern Chile, many streams are characterized by perennial flow and support dense in-stream wetlands. These streams possess sequences of wetland deposits as fluvial terraces that record past changes in the water table. We mapped and radiocarbon dated a well-preserved sequence of in-stream wetland deposits along a 4.3-km reach of the Río San Salvador in the Calama basin to determine the relationship between regional climate change and the incision of in-stream wetlands. -
Plate Tectonic Setting of the Andean Cordillera
183 by Victor A. Ramos Plate tectonic setting of the Andean Cordillera Laboratorio de Tectónica Andina, Universidad de Buenos Aires, Argentina. E-mail: [email protected] The Andes are a natural laboratory for the study of the acterize the different segments are widely variable. The present interaction between subduction of the oceanic plate and overview will focus on the major geological differences among these segments, based on today’s plate-tectonic knowledge of this moun- active geological processes. Inter- and intraplate seis- tain chain. micity, volcanic activity, thick- and thin-skinned fold and thrust belts, and foreland basin subsidence, in con- junction with space geodetic observations, contribute to Major geological provinces characterize the present plate tectonic setting of discrete The Andes north of the Golfo de Guayaquil are unique, as estab- segments of the Andes. The inherited geological history, lished by Gansser (1973). The Northern Andes record an important as well as the present tectonic setting, is responsible for accretion of oceanic crust during Jurassic, late Cretaceous, and Pale- the unique geology of the Northern, Central, and South- ogene times. As a result, the Western Cordillera of Colombia and Ecuador is mainly constituted of an oceanic basement that during ern Andes. The Northern Andes are the result of Meso- accretion was related to ophiolite obduction, important penetrative zoic and Cenozoic collisions of oceanic terranes, prior deformation and metamorphism, in cases up to blue schist facies. to the present Andean-type setting. The Central Andes Further north, the emplacement of the Caribbean nappes was related to the collision of an island arc system, the Bonaire block, during have a long history of subduction and volcanic arc Paleogene times (Bosch and Rodríguez, 1992, Kellogg and Bonini, activity, while the Southern Andes record the closing of 1982).