380 research outputs found

    Risk assessment and mitigation at Copahue Volcano

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    "Risk assessment" is a relatively new concept in Argentina, since the veryfirst hazard map was only recently constructed on the basis of the 1992 eruption of Copahue volcano (Patagonia). Copahue is considered a very active volcanic system since 13 eruptive events have been recognized overthe last 260 years. Most the events are phreatic and phreato-magmatic withVEI ≤ 2; nevertheless such eruptions represent a threat for thecommunities living in the surrounding areas of the emission centre, not only because of pyroclastic flows and tephra fall (the nearby villages,Caviahue and Copahue, have so far only experienced ash fallout), but also due to the possible formation of mud flows and flank collapse triggered by the volcanic activity. Owing to the frequent eruptions of Copahue, the most recent ones (2000, 2012) showed an increasing explosive character, hazard survey actions, such as thematic maps and contingency plans areconstantly, though slowly, modified. The risk assessment described in this chapter calls for the implementation of the monitoring network in the Argentina side of the volcano, since the only currently active seismic stations (OVDAS) are located in the Chilean side of the volcanic edifice, Copahue volcano lying at the border between the two countries.Moreover, the Chilean observatory adopts criteria of alert levels, which are distinctly different with respect to those of Argentina Civil Defense,producing misleading information to the population. The villages of Copahue and Caviahue are regarded as extremely vulnerable to possible future eruptions if larger magnitude events should occur. A review of the presently available potential hazard map, an improvement of people's education about the volcanic risks and a more interactive cooperation between the Chilean and Argentina scientific and administrative institutions are some of the immediate counter measures to be taken into account before a new explosive phase at Copahue.Fil: Caselli, Alberto Tomás. Universidad Nacional de Rio Negro. Sede Alto Valle. Laboratorio de Estudio y Seguimiento de Volcanes Activos.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Liccioli, Caterina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Tassi, Franco. Università degli Studi di Firenze; Itali

    Geochemistry of the magmatic-hydrothermal fluid reservoir of Copahue volcano (Argentina): insights from the chemical and isotopic features of fumarolic discharges

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    This study present the chemical (inorganic and organic) and isotopic compositions (d13C-CO2, d15N, 3He/4He, 40Ar/36Ar, d13C-CH4, dD-CH4, and dD-H2O and d18O-H2O) of gases from fluid discharges located at the foot of Copahue volcano. Gas samples were collected during 6 campaigns carried out from 1976 to 2012. Gas composition is typical of hydrothermal fluids from volcanic areas, since it consists of dominant CO2 and relatively high concentrations of H2S, H2, CH4 and N2. The isotopic ratios of He are the highest observed for a Southern American volcano to date (R/Ra up to 7.94). This feature is not common for gases from a classic arc-like setting, and is possibly related to an extensional regime subdued to asthenospheric thinning. The CO2/3He ratios (from 1.4 to 8.8×109) slightly exceeding that of MORB gases, and the d15N values (+5.3 to +5.5 ? vs. air) point to an occurrence of an additional crustal source for CO2 and N2. Gas discharges of the northern sector of the volcanic edifice are likely produced by mixing of hydrothermal gases with fluids from a shallow source permeating through local fault systems. Gas geothermometry based on chemical reactions characterized by slow kinetics, such as those involving the CO2-CH4 redox pair, are quenched at temperatures (~260 °C) and redox conditions [log(XH2/XH2O) = -2.8)] consistent with those measured in the goethermal wells. On the contrary, the C3H6-C3H8 pair, H2 and CO tend to re-adjust at decreasing temperatures and more oxidizing conditions [log(XH2/XH2O) ≤ -3.4] in the uprising vapor phase. The hydrothermal reservoir is mainly recharged by meteoric water whose isotopic signature is modified by water-rock interactions. The N2/He ratios measured in 2006-2007 were significantly lower than those of 2012, possibly due to variations of N2-bearing species in sediments interacting with the magmatic source. Considering that the R/Ra values of the 2006-2007 period were significantly higher than those measured in 2012, such compositional variation may also be explained by the injection of fresh N2and 3He-rich magma that triggered the 2000 eruption. This hypothesis, although speculative since no geochemical data of fumaroles are available from 1997 to 2006, implies that a geochemical monitoring of inert gas compounds discharged from the hydrothermal emissions could be used to detect the occurrence at depth of injections of new magma batches.Fil: Tassi, Franco. Università degli Studi di Firenze; ItaliaFil: Agusto, Mariano Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Vaselli, Orlando. Università degli Studi di Firenze; ItaliaFil: Chiodini, Giovanni. Istituto Nazionale di Geofisica e Vulcanologia; Itali

    Structural architecture releasing deep-sourced carbon dioxide diffuse degassing at the Caviahue – Copahue Volcanic Complex

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    The link between carbon dioxide diffuse degassing and its structural control was examined in the Caviahue – Copahue Volcanic Complex, over an area of approximately 10 km 2 that encompasses five hydrothermal sites, namely, Anfiteatro, Copahue town, Las Maquinitas I, Las Maquinitas II and Las Máquinas. Both geochemical and structural approaches were applied in order to investigate the structural scenario releasing hydrothermal fluids in this area. Also, the first isotopic analysis of soil CO 2 degassing in the Andean region is presented. The geochemical analysis shows well-defined CO 2 diffuse degassing structures in Copahue town, Las Maquinitas I, Las Maquinitas II and Las Máquinas hydrothermal sites. Soil diffuse CO 2 is fed by multiple sources: a deep, magmatic – hydrothermal, source, a biogenic source and a mixed source. The structural analysis indicates the presence of an extensional regime that gives place to three structural trends, consisting of NE-SW trending normal faults, NW-SE sinistral strike-slip faults and ENE-WSW right lateral strike-slip faults. The comparison between diffuse degassing structures directions and faults directions suggests that there is a structural control on diffuse degassing. Diffuse CO 2 is released through an early extensional setting, and it is emitted through normal faults, strike-slip faults and through areas with higher structural damage, such as relay areas between fault segments and terminations of individual fault segments.Fil: Lamberti, María Clara Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Vigide, Nicolás Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Venturi, Stefanía. Consiglio Nazionale delle Ricerche; ItaliaFil: Agusto, Mariano Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Yagupsky, Daniel Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Winocur, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Barcelona, Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Velez, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Cardellini, Carlo. Università di Perugia; ItaliaFil: Tassi, Franco. Università degli Studi di Firenze; Itali

    The 2012–2016 eruptive cycle at Copahue volcano (Argentina) versus the peripheral gas manifestations: hints from the chemical and isotopic features of fumarolic fluids

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    This study presents the chemical and isotopic compositions of hydrothermal gases from fumaroles discharging around Copahue volcano (Argentina). Gas samples, including those from two fumaroles at the active summit crater, were collected during 13 surveys carried out by different research teams from 1976 to February 2016. The time-series of H2, CO and light hydrocarbons showed episodic increases related to the main events of the last eruptive cycle that started on 19 July 2012. Concentration peaks were likely caused by enhanced input of hot magmatic fluids affecting the hydrothermal reservoir. These data contrast with the temporal variations shown by Rc/Ra and δ13C-CO2 values in 2012–2014, which indicated an increasing input from a crustal fluid source. In 2015–2016, however, these isotopic parameters showed opposite trends; their composition became closer to that of the two summit fumaroles, which possibly corresponds to that of the deep magmatic-related end-member. The delayed and reduced compositional changes in the peripheral hydrothermal fluid discharge in response to the 2012–2016 eruptive events suggest that geochemical surveys of these emissions are unlikely to provide premonitory signals of volcanic unrest if the volcanic activity remains centered in the main crater. Instead, an instrument which is able to provide measurements of volcanic gases in the air (e.g. MultiGAS) may be used to detect changes at the summit crater. Otherwise, monitoring of seismic activity and ground deformation, as well as the periodic measurement of the chemistry of the water in the Rio Agrio, which is fed by thermal discharge from the summit crater, seem to represent the most reliable means of monitoring at Copahue. However, the relative compositional stability of the hydrothermal reservoir is a great advantage in terms of geothermal resource exploitation and could encourage new investments in the Copahue geothermal project which was abandoned in the 1990s.Fil: Tassi, F.. Consiglio Nazionale delle Ricerche; Italia. Università degli Studi di Firenze; ItaliaFil: Agusto, Mariano Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Lamberti, María Clara Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Caselli, Alberto Tomás. Universidad Nacional de Río Negro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pecoraino, G.. Istituto Nazionale Di Geofisica E Vulcanologia; ItaliaFil: Caponio, Cecilia. Università degli Studi di Firenze; ItaliaFil: Szentivanyi, Juliana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Venturi, S.. Consiglio Nazionale delle Ricerche; Italia. Università degli Studi di Firenze; ItaliaFil: Vaselli, O.. Consiglio Nazionale delle Ricerche; Italia. Università degli Studi di Firenze; Itali

    The 2012 Eruption

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    This contribution is a detailed description of the precursory activity and theeruptive events that took place during July and December 2012 at Copahue volcano, based on field observations and geophysical and geochemical monitoring. After the Mw 8.8 Chilean earthquake on February 27th 2010, several signals of anomalous behavior were detected at Copahue, revealing the instability of the volcanic system. Starting from July 2012 a phreatic activity occurred with emission of a low amount of material mainly constituted by rocks from the volcanic conduit and sediments from the bottom of the crater lake. Seismic activity and degassing continued until December 22nd when the eruption started with an opening phreatic event that rapidly evolved to a phreatomagmatic, and finally a magmatic eruption.Fil: Caselli, Alberto Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Agusto, Mariano Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Velez, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Forte, Pablo Brian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Bengoa, Cintia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Daga, Romina Betiana. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Albite, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentin

    Numerical modeling of compound channel flows with high rugosity areas, an openTELEMAC approach

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    Máster en Ingeniería de Caminos, Canales y Puertos (Plan 2020

    Actividad antagónica de una cepa de Bacillus sp. aislada en Córdoba, Argentina contra Macrophomina phaseolina (Tassi) Goid

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    The antifungal activity of Bacillus spp.strains has been already reported against a different number of phytopathogenicfungi3. Some species belonging to thisgenus (i.e. B. subtilis, B. pumilus and B. licheniformis) are considered GRAS (generally regarding as safe) microorganisms and exhibit potential to enhance plant growth by the production of an amplenumber of beneficial substances1,portraying these species as an environmentally friendly alternative tochemical fungicides. Macrophomina phaseolina (Tassi) Goid is a wide range soil-bornephytopathogenic fungus causing charcoal rot to several significant plant crops in Argentina (i.e. soybean, common bean,peanuts and corn)5,6 and is also capableto affect more than five hundred plant species worldwide4. Its ability to infect these hostplants is commonly correlated to the production of viable sclerotia, anon-sporic resistance structure constituted by a mass of densely packed hyphae, in the field5. In this work, we report theisolation of a Bacillus sp. strain 11.1 obtained from soil samples from Córdoba Province,Argentina2exhibiting a strongantagonistic activity against M. phaseolina. In order to analyse thepotential antagonistic effect of strain 11.1, both microorganisms were grown on dual culture platescontained potato dextrose agar (PDA) and tryptone soya agar (TSA) (1:1 v/v) and incubated for 48-72hours at 28ºC (Figure 1). An important and irreversible inhibition of the fungal growth was showed (Figure1A). In addition, the fungal mycelium located at the edge of the inhibited region was analysed bymicroscopic examination. The most evident antagonistic effect over the fungus was depicted by the lack ofblack pigmentation and the reduced size of formed sclerotiain comparison with the control (Figure 1B and C).Fil: Felipe, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; ArgentinaFil: Palma, Leopoldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; ArgentinaFil: Yaryura, Pablo Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; Argentin

    Structural control on carbon dioxide diffuse degassing at the Caviahue – Copahue Volcanic Complex, Argentina

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    The Caviahue – Copahue Volcanic Complex (CCVC) is located within the Andean Cordillera, in the Neuquén province, Argentina. This tectono-magmatic system lies within the northern termination of the Liquiñe – Ofqui fault zone, a 1,200-km-long intraarc strike-slip fault system. Fluid emissions at this active volcanic complex are fed by a hydrothermal reservoir located at 800 m depth, mostly recharged by meteoric water. The reservoir is heated by a magmatic chamber located at 5 km depth, which also provides the system with magmatic gases. Fluid emissions at the CCVC release over 200 tons per day of soil diffuse CO2. The aim of this study is to evaluate the control that the local structural architecture exerts on CO2 flow, from the hydrothermal reservoir to the surface.Fil: Lamberti, María Clara Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Vigide, Nicolás Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Venturi, Stefanía. Consiglio Nazionale delle Ricerche; ItaliaFil: Agusto, Mariano Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Yagupsky, Daniel Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Winocur, Diego Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Barcelona, Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Velez, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Tassi, Franco. Università degli Studi di Firenze; ItaliaEGU General Assembly 2019VienaAustriaEuropean Geosciences Unio

    Numerical modelling of river processes: flow and river bed deformation

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    The morphology of alluvial river channels is a consequence of complex interaction among a number of constituent physical processes, such as flow, sediment transport and river bed deformation. This is, an alluvial river channel is formed from its own sediment. From time to time, alluvial river channels are subject to disturbances in their immediate environment caused by natural or artificial effects, namely variable inflow, sediment supply, and various human activities such as channel regulation or reservoir construction. Flows are primary driving forces governing the behaviour of alluvial river morphology. An increase in flow magnitude may initiate bed surface movements and bank erosion, once the force exerted by the flood event has passed some threshold for movement or erosion. The timing and frequency of flood may also have profound effects on a population; a flood can cause catastrophic damage to civil infrastructure located on or nearby the river. The wish to improve the safety situation and to foresee the impact of the ever growing human interference with the environment, has created a need for reliable predictions of complex situations found in nature. The socio-economical and political importance of alluvial systems has also increased this need. In early time, research methodologies of river processes were primarily based on field observation and laboratory scale modelling. Laboratory scale models and field measurements have been and are still essential for the understanding of complex river processes, and are used as design and verification tools, despite their high cost of construction, maintenance and operation. An alternative that has been growing in popularity and acceptance is river modelling. River modelling is the analysis and simulation of flow conditions based on the formulation and solution of mathematical relationships expressing hydraulic principles. In this thesis, we focused our efforts on two main activities associated with the application of river modelling to solve particular river hydraulics problems: (i) In Chapters 2 and 3, we perform numerical simulations based on the solution of the shallow water equations to predict flow resistance and eddy viscosity for vegetated floodplains, and we present a numerical reconstruction of the catastrophic flooding of Santa Fe City, Argentina. (ii) In Chapters 4 and 5, the derivation, design, and implementation of a discontinuous Galerkin method for the solution of the shallow water, sediment transport, and bed evolution equations is presented. Our numerical scheme shows ability to handle advection dominated flows, including problems with hydraulic and sediment jumps or bores. Additionally, its inherent mass and momentum conservation properties make it suitable for coupling flow and sediment transport. We have developed a mathematical-numerical tool that enables us to reproduce, and eventually, to predict morphological changes produced in alluvial systems, in response to highly varying flow regimes

    Prehistoric to historic volcanic activity at Copahue Volcano

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    Copahue is one of the most active volcanic centers in Argentina. Despite the relatively intense volcanic activity its prehistoric events are poorly known. In this work, after a brief introduction on the geological and structural control on this volcanic complex, we have summarized the events that have led to the construction of the current volcanic edifice and its historical eruptive activity. Prehistoric events were divided into three main stages: pre-, sin- and post-glacial based on the stratigraphic relations observed in the field by previous authors. At least 13 eruptions were recorded during the last 260 years. Although the scarce detailed historical information, the eruptive style outlined by the available reports and data seems to indicate a general phreatic and phreato-magmatic character over the last two centuries, whereas the most recent (2000 and 2012) eruptive events, characterized by the occurrence of magmatic pulses, have a strombolian character.Fil: Caselli, Alberto Tomás. Universidad Nacional de Río Negro. Sede Alto Valle. Laboratorio de Estudio y Seguimiento de Volcanes Activos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Velez, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Agusto, Mariano Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Liccioli, Caterina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Orlando Vaselli. Università degli Studi di Firenze; Itali
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