Catastrophic slab loss in southwestern Pangea preserved in the mantle and igneous record

The Choiyoi Magmatic Province represents a major episode of silicic magmatism in southwestern Pangea in the mid-Permian-Triassic, the origin of which remains intensely debated. Here, we integrate plate-kinematic reconstructions and the lower mantle slab record beneath southwestern Pangea that provide clues on late Paleozoic-Mesozoic subducting slab configurations. Also, we compile geochronological information and analyze geochemical data using tectono-magmatic discrimination diagrams. We demonstrate that this magmatic event resulted from a large-scale slab loss. This is supported by a paleogeographic coincidence between a reconstructed 2,800-3,000-km-wide slab gap and the Choiyoi Magmatic Province and geochemical data indicating a slab break-off fingerprint in the latter. The slab break-off event is compatible with Permian paleogeographic modifications in southwestern Pangea. These findings render the Choiyoi Magmatic Province the oldest example of a geophysically constrained slab loss event and open new avenues to assess the geodynamic setting of silicic large igneous provinces back to the late Paleozoic.Fil: Gianni, Guido Martin. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Introduction to Journal of South American Earth Sciences special issue on “Magmatism of southernmost South America”

complex magmatic history due to the occurrence of multiple large-scalegeological processes that include mantle plumes impingements, slabwindows opening, collisional episodes, normal and flat subductionevents, mantle transition zone-derived melts ascent, slab break-offevents, etc. (e.g., Mpodozis and Kay, 1992; Gorring et al., 1997; Rileyet al., 2001; Pankhurst et al., 2006; Kay et al., 2007; Ramos, 2008;Breitsprecher and Thorkerlson, 2009; Arag´on et al., 2013; Gianni et al.,2018; Navarrete et al., 2019; 2020; Iannelli et al., 2020). Although thismagmatic history began during the Neoproterozoic, the igneous activityof the last 300 Myr has been remarkably intense and voluminous,constituting one of the most distinctive geological features of this region.So much so that three Phanerozoic Large Igneous Provinces (LIPs) havebeen proposed (Kay et al., 1989; Pankhurst et al., 1998; Kay et al., 2007;Bastías-Mercado et al., 2020 ? this special issue). The first of them linkedto the Permian-Triassic subduction events (Choiyoi SLIP - Bastías-Mercado et al. this especial issue, and references therein; Oliveroset al., 2019), although there are also proposals that have suggested anorigin related to slab-breakoff episodes (e.g., Mpodozis and Kay, 1992;Pankhurst et al., 2006). The second would have been generated by theJurassic Karoo mantle plume impingement added to the paleo-pacificsubduction during the beginning of the Gondwana breakup (ChonAike SLIP - e.g., Kay et al., 1989; Pankhurst et al., 1998), whereas theorigin of the Oligocene-Miocene third province (Somuncura LIP ? Kayet al., 2007) is still under discussion. There are proposals that invoke amantle plume impingement (Kay et al., 2007), a lithospheric delaminationevent (Remesal et al., 2012), as well as the mantle transitionzone-derived melts ascent due to the Farallon slab stagnation (Navarreteet al., 2020), between others. In this special issue, most of the articles arelinked to these Permian-Triassic, Jurassic and mid-Cenozoic LIPs(Fig. 1), although multiple subduction-related magmatic events are alsoincluded, such as the formation of the Patagonian Batholith (e.g., Pankhurstet al., 1999) and the eruption of the volcanic products linked tothe magmatism of the Andean subduction zone (e.g., Rapela et al., 1984;1988).From the economic point of view, the socio-economic developmentof Chile and Argentina was marked by the magmatism of the southernmostSouth American region. In this sense, the Jurassic magmatismof Patagonia gave rise to numerous precious metals hydro-thermal largemineral deposits (e.g., Schalamuk et al., 1997; Echavarría et al., 2005;Guido and Campbell, 2011; Permuy Vidal et al., 2016; Tassara et al.,2017), whereas the Cenozoic intraplate magmatism of Patagoniafavored the hydrocarbon maturation in Patagonian oil and gas producingMesozoic basins (e.g., Rodriguez and Littke, 2001; Spacapan et al.,2018). Also, giant porphyry copper deposits were produced by theMeso-Cenozoic subduction-related magmatism in the Andean region (e.g., Mpodozis and Cornejo, 2012; Lee and Tang, 2020).Therefore, new contributions that improve the comprehension of thelarge magmatic episodes of southernmost South America are highlyrelevant for the general geological knowledge of this region, and theirinterest exceeds that of the academic geological community.Fil: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Zaffarana, Claudia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentin

Deformación del manto de transición bajo la Patagonia central por el estancamiento de la losa de Aluk: ¿La causa del magmatismo cuaternario de Chubut?

El avance de las técnicas geofísicas junto al incesante progreso de la petrología experimental, han incrementado notablemente el conocimiento geológico y geodinámico del interior terrestre en las últimas décadas. Los adelantos logrados en la comprensión del proceso de subducción han sido notables, pudiéndose actualmente determinar con cierta claridad el recorrido de las litósferas oceánicas hacia la base del manto inferior (p.ej., van der Meer et al., 2018). Un aspecto desconocido previo al advenimiento de la geofísica moderna, es el estancamiento de losas oceánicas en el límite manto superior-manto inferior (~660 Km.), lo cual ha sido recientemente documentado en numerosos ambientes convergentes del mundo (véase Fukao et al., 2009), vinculado directamente al incremento de densidad que registra la porción inferior del manto que retrasa la penetración de las litósferas subductadas. Numerosos episodios volcánicos de intraplaca han sido ahora vinculados a estos estancamientos, muchos de los cuales eran previamente atribuidos a plumas mantélicas (p.ej., Zhang et al., 2014).Fil: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Massaferro, Gabriela Isabel. Universidad Nacional de la Patagonia. Facultad de Ciencias Naturales. Sede Puerto Madryn; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; ArgentinaVII Jornadas de las Ciencias de la Tierra: Dr. Eduardo MusacchioComodoro RivadaviaArgentinaUniversidad Nacional de la Patagonia San Juan Bosco. Facultad de Ciencias Naturales y Ciencias de la Salud. Departamento de Geologí

Surface and mantle records reveal an ancient slab tear beneath Gondwana

Vertical slab-tearing has been widely reported in modern convergent settings profoundly influencing subduction and mantle dynamics. However, evaluating a similar impact in ancient convergent settings, where oceanic plates have been subducted and the geological record is limited, remains challenging. In this study, we correlate the lower mantle structure, which retained the past subduction configuration, with the upper-plate geological record to show a deep slab rupture interpreted as a large-scale tearing event in the early Mesozoic beneath southwestern Gondwana. For this purpose, we integrated geochronological and geological datasets with P-wave global seismic tomography and plate-kinematic reconstructions. The development of a Late Triassic-Early Jurassic slab-tearing episode supports (i) a slab gap at lower mantle depths, (ii) a contrasting spatiotemporal magmatic evolution, (iii) a lull in arc activity, and (iv) intraplate extension and magmatism in the Neuquén and Colorado basins. This finding not only has implications for identifying past examples of a fundamental process that shapes subduction zones, but also illustrates an additional mechanism to trigger slab-tearing in which plate rupture is caused by opposite rotation of slab segments.Fil: Gianni, Guido Martin. 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"; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro. Departamento de Geología; ArgentinaFil: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; Argentin

Ghost-arc geochemical anomaly at a spreading ridge caused by supersized flat subduction

The Southern Atlantic-Southwest Indian ridges (SASWIR) host mid-ocean ridge basalts with a residual subduction-related geochemical fingerprint (i.e., a ghost-arc signature) of unclear origin. Here, we show through an analysis of plate kinematic reconstructions and seismic tomography models that the SASWIR subduction-modified mantle source formed in the Jurassic close to the Georgia Islands slab (GI) and remained near-stationary in the mantle reference frame. In this analysis, the GI lies far inboard the Jurassic Patagonian-Antarctic Peninsula active margin. This was formerly attributed to a large-scale flat subduction event in the Late Triassic-Early Jurassic. We propose that during this flat slab stage, the subduction-modified mantle areas beneath the Mesozoic active margin and surrounding sutures zones may have been bulldozed inland by >2280 km. After the demise of the flat slab, this mantle anomaly remained near-stationary and was sampled by the Karoo mantle plume 183 Million years (Myr) ago and again since 55 Myr ago by the SASWIR. We refer to this process as asthenospheric anomaly telescoping. This study provides a hitherto unrecognized geodynamic effect of flat subduction, the viability of which we support through numerical modeling.G. M. G. and C. R. N. recognize the support given by CONICET and the funding given by the Universidad Nacional de la Patagonia San Juan Bosco (Grant number: CIUNPAT no. 1399). S. Z. and J. L. acknowledge the funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 777778. S.Z. acknowledges the funding of Project PID2020-113463RB-C32 funded by MCIN/AEI /10.13039/501100011033 and the funding of Generalitat de Catalunya via the 2021 SGR 01049.Peer ReviewedPostprint (published version

Osmium isotopes fingerprint mantle controls on the genesis of an epithermal gold province

The formation of crustal blocks enriched with gold (Au) deposits above subduction zones is intimately bound to the genesis and evolution of magmatic-hydrothermal systems. A longstanding question, however, is whether the metal fertility of these systems stems from distinct sources that are anomalously enriched in Au or from subsequent processes occurring during crustal magma emplacement and hydrothermal activity. The Deseado Massif auriferous province in southern Patagonia (Argentina) is a unique place to test these contrasting hypotheses because Au-bearing mantle xenoliths indicate the presence of an underlying Au-rich lithospheric mantle reservoir. However, direct geochemical links between the Au-rich mantle source and the formation of the Deseado Massif auriferous province in the overlying crust remain to be established. To address this prominent gap in knowledge, we used sulfide Re-Os geochronology to identify the source of Au at Cerro Vanguardia, the largest low-sulfidation epithermal Au-Ag deposit in the Deseado Massif. Pyrite from high-grade Au quartz veins yielded an isochron age of 147.4 ± 2.9 Ma (mean square of weighted deviates = 1.04, n = 8) and an initial 187Os/188Os ratio of 0.26 ± 0.01, fingerprinting a dominant mantle control for the source of Os and, by inference, the source of Au. Our data provide a unique geochemical linkage between an Au-rich subcontinental lithospheric mantle source and the genesis of epithermal Au deposits, supporting the hypothesis that pre-enriched mantle domains may be a critical factor underpinning the global-scale localization of Au provinces.Fil: Tassara, Santiago. University of Yale; Estados UnidosFil: Rooney, Alan D.. University of Yale; Estados UnidosFil: Ague, Jay. J.. University of Yale; Estados UnidosFil: Guido, Diego Martin. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Reich, Martin. Universidad de Chile; ChileFil: Barra, Fernando. Universidad de Chile; ChileFil: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Northward propagation of Andean genesis: Insights from Early Cretaceous synorogenic deposits in the Aysén-Río Mayo basin

Decoding the earliest orogenic stages in the Andes, the largest subduction orogen on Earth is fundamental to understanding changes in climate, drainage organization, and biodiversity in South America. Furthermore, it is crucial to unraveling the driving mechanism behind the initiation of orogeny. To track the earliest stages of Andean growth, we studied the Aysén/Río Mayo basin (ARB) in the North Patagonian Andes. The small degree of Cenozoic tectonic overprinting in this part of the Andes has allowed outstanding preservation of the deformational and sedimentary record of the earliest Andean deformation. In this study, we employ a multidisciplinary approach involving structural geology, sedimentology, geochronology, and provenance studies from the Early Cretaceous Apeleg Formation (~130?122 Ma) in the ARB and geochemical analysis of intrusive Cretaceous igneous rocks. Particularly, the recognition of syncontractional growth strata at several localities indicate a syntectonic origin for this unit and provide additional structural evidence of Early Cretaceous contraction in the North Patagonian Andes. Thus, the Apeleg Formation is interpreted as deposited during a contractional basin stage. Geochemical data from Aptian-Albian intrusive igneous rocks indicate that initial contraction emplaced over thinned crust likely inherited from the Jurassic extension in the ARB. This stage is then compared with a new synthesis of the earliest Cretaceous contraction along the Andes. This analysis reveals that the ARB likely holds the oldest post-Gondwanic synorogenic unit along the orogen and more significantly, that Andean birth was a diachronous process which propagated northward since the late Early Cretaceous. The latter findings have major implications for the evolution of the Andes and shed light into the driving mechanism behind initial orogeny.Fil: Gianni, Guido Martin. 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: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Echaurren Gonzalez, Andres. 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: Díaz, Marianela Ximena Yasmin. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Butler, Kristina L.. University of Texas at Austin; Estados UnidosFil: Horton, Brian K.. University of Texas at Austin; Estados UnidosFil: Encinas, Alfonso. Universidad de Concepción; ChileFil: Folguera Telichevsky, Andres. 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"; Argentin

A geodynamic model linking Cretaceous orogeny, arc migration, foreland dynamic subsidence and marine ingression in southern South America

This study synthesizes the tectonomagmatic evolution of the Andes between 35°30′S to 48°S with the aim to spotlight early contractional phases on Andean orogenic building and to analyze their potential driving processes. We examine early tectonic stages of the different fold-thrust belts that compose this Andean segment. Additionally, we analyzed the spatio-temporal magmatic arc evolution as a proxy of dynamic changes in Andean subduction during critical tectonic stages of orogenic construction. This revision proposes a hypothesis related the existence of a continuous large-scale flat subduction setting in Cretaceous times with a similar size to the present-largest flat-slab setting on earth. This potential process would have initiated diachronically in the late Early Cretaceous and achieved full development in Late Cretaceous to earliest Paleocene times, constructing a series of fold-thrust belts on the retro-arc zone from 35°30′S to 48°S. Moreover, we assess major paleogeographic changes that took place during flat-slab full development in Maastrichtian-Danian times. At this moment, an enigmatic Atlantic-derived marine flooding covered the Patagonian foreland reaching as far as the Andean foothills. Based on flexural and dynamic topography analyses, we suggest that focused dynamic subsidence at the edge of the flat-slab may explain sudden marine ingression previously linked to continental tilting and orogenic loading during a high sea level global stage. Finally, flat-subduction destabilization could have triggered massive outpouring of synextensional intraplate volcanic rocks in southern South America and the arc retraction in late Paleogene to early Neogene times.Fil: Gianni, Guido Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; ArgentinaFil: Davila, Federico Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Echaurren Gonzalez, Andres. 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: Fennell, Lucas Martín. 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: Tobal, Jonathan Elías. 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: Navarrete Granzotto, César Rodrigo. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Quezada, Paulo. Universidad Andrés Bello; ChileFil: Folguera Telichevsky, Andres. 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: Gimenez, Mario Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentin

The volcanism of the Jurassic Chon Aike Silicic LIP influenced by Paleozoic inherited crustal structures in the northeastern Deseado Massif, Patagonia

An area of ∼40 km2 located in the northeastern sector of the Deseado Massif is detailed studied, in which Paleozoic metamorphic and Jurassic volcanic rocks crop out. Two genetically linked and compositionally different Jurassic volcanic events of the Chon Aike Silicic LIP are documented by geological mapping and lithofacies and petrographic analyses. The first event was only represented by andesitic lava flows assignable to the intermediate portion of the Bahía Laura Volcanic Complex (Bajo Pobre Formation). The second was represented by the acidic rocks of the Bahía Laura Volcanic Complex (Chon Aike and La Matilde formations) and it was constituted by low-grade and moderate grade ignimbrites, pyroclastic fall deposits (ash tuffs) and several lava bodies (rhyolitic lava domes and lava flows). Firstly, the effusive eruptions dominated during the intermediate magmatic eruptions, whereas the explosives mechanisms dominated during the first stage of the acidic magma extrusion, to end with effusive eruptions of previously degassed magma. According to the morphology of the NNW-elongated lava domes (feeder conduits plugs) and internal measurements carried out on these rhyolitic bodies, fissure conduits are interpreted, which were directly controlled by the Paleozoic inherited structures during the Jurassic extensional tectonic reactivation ascribed to the initial stages of the Gondwana breakup.Fil: Navarrete Granzotto, César Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro. Departamento de Geología; Argentin

El estancamiento de la loza de Aluk: ¿La causa del magmatismo cuaternario de Chubut?

Litósferas oceánicas estancadas en el límite manto superior-inferior han sido recientemente documentadas en numerosos ambientes convergentes del mundo, lo cual se vincula al incremento de densidad que registra la porción inferior del manto. Luego de su descubrimiento, diversos episodios volcánicos de intraplaca que eran previamente atribuidos a plumas mantélicas, han sido ahora vinculados a estos estancamientos. Por otra parte, descubrimientos recientes han confirmado la existencia de fases minerales hidratadas a profundidades del manto de transición (~410 - 660 km), conocidas como wadsleyita (olivino β) y ringwoodita (olivino γ); lo cual ha fundado propuestas que sugieren que su deformación vinculada a cambios en la dinámica de una subducción cercana (plegamiento o alzamiento), es capaz de desencadenar fusión de la astenósfera suprayacente debido a una liberación de fluidos por la destrucción de la estructura de la wadsleyita.Fil: Navarrete Granzotto, César Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro; ArgentinaFil: Massaferro, Gabriela Isabel. Universidad Nacional de la Patagonia. Facultad de Ciencias Naturales. Sede Puerto Madryn; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina1° Congreso de la Asociación Latinoamericana de VolcanologíaAntofagastaChileAsociación Latinoamericana de Volcanologí