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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; Argentina Fil: 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; Argentina Fil: 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; Argentina

As the archetype of mountain building in subduction zones, the Central Andes has constituted an excellent example for investigating mountain-building processes for decades, but the mechanism by which orogenic growth occurs remains debated. In this study we investigate the Southern Central Andes, between 22° and 35°S, by examining the along-strike variations in Cenozoic uplift history (

Los eventos sísmicos no destructivos son una oportunidad para la alfabetización científica de la población, y pueden contribuir a la resiliencia de la sociedad frente al peligro natural que representa la sismicidad. Para evaluar cómo se transmite esta información, tomamos como caso de estudio 231 notas publicadas en medios locales de la provincia de Mendoza, Argentina. Observamos que no siempre presentan la información completa necesaria para caracterizar el evento sísmico, y en ocasiones presentan la información de manera confusa. Con el fin de mejorar la comprensión de la información publicada, presentamos una lista de los parámetros que deben incluirse: (1) ubicación del epicentro, (2) magnitud, (3) profundidad, (4) fuente de la información, y (5) intensidades, en el caso de sismos sentidos. Discutimos brevemente la importancia de cada uno de estos parámetros para una mejor comprensión del peligro sísmico. Fil: Mescua, Jose Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: 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; Argentina Fil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

In this work, we develop a multidisciplinary approach to investigate a geothermal system located at the volcanic arc of a subduction-related orogen and highlight the interplay between active tectonism, stress field and fluid migration. By using results of field investigations from the Tinguiririca geothermal field in the High Andes of Chile (35°S), empirical analysis, and numerical models of static stress variations, we proposed a geomechanical model for evaluating the distribution of hydrothermal manifestations in a seismically-active region. The present geomechanical model follows four major steps: (1) development of the 3D structural model of fault pattern; (2) estimation of the in-situ stress field; (3) calculation of the resolved-shear-to-normal-stress ratio (slip tendency) on each fault with varying geomechanical parameters (coefficient of friction, pore pressure and cohesion) as inputs; and (4) estimation of Coulomb static stress changes as a consequence of failure in a nearby fault. Through combination of all these analyses, we characterize in detail both the active deformation in the geothermal field and its relationship with hot fluid migration. Fil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Álvarez, P.. TEHEMA S.A.; Chile Fil: 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; Argentina Fil: Godoy, E.. TEHEMA S.A.; Chile Fil: Lossada, Ana Clara. 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 Fil: Mescua, Jose Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Barrionuevo, Matías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Suriano, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

Fil: Montenegro, Veronica. Universidad Nacional de Río Negro, Instituto de Investigación en Paleobiología y Geología. Río Negro, Argentina. Fil: Spagnotto, Silvina. Universidad Nacional de Río Negro, Instituto de Investigación en Paleobiología y Geología. Río Negro, Argentina. Fil: Legrand, Denis. Universidad Nacional Autónoma de México, Instituto de Geofísica, Unidad Michoacán. Morelia, Mexico. Fil: Caselli, Alberto. Universidad Nacional de Río Negro, Instituto de Investigación en Paleobiología y Geología. Río Negro, Argentina. Understanding interactions between tectonic faults and a nearby active volcano is often realized by combining seismic and field observations. A good example of such an interaction is the Caviahue caldera. It is located in an intra-arc extensional pull-apart basin, within a transition zone joining the northern part of the right-lateral strike-slip Liquiñe-Ofqui Fault System and the thrust-fault Antiñir-Copahue fault zone. Most of the active volcanoes in South Chile are related to the Liquiñe-Ofqui Fault System. Some faults located inside the Caviahue caldera were described with reverse mechanisms by some studies whereas they were found to be normal by others. In order to discriminate the actual focal mechanisms, two seismic clusters that occurred in 2017 and 2018 inside the Caviahue rectangular caldera, close to the active Copahue volcano, were studied. Earthquakes (520) were located; focal mechanisms (56) were determined from which an average seismic moment tensor was calculated. The locations and focal mechanisms of the earthquakes allow splitting the seismicity into two main regions, one of tectonic origin (with strike-slip faults) and another one of volcanic origin (with normal faults). The first seismic cluster is located close to Caviahue village, with strike-slip focal mechanisms, in an NNE direction as the nearby Liquiñe-Ofqui Fault strikes. The other part of the seismicity is located close to the northeastern structures of Copahue volcano, in the hydrothermal zone of Anfiteatro, Termas de Copahue, and Maquinitas. It is oriented in an NE direction and is composed of earthquakes with normal focal mechanisms, not reverse as postulated in past studies. The active Copahue volcano lies in the SW prolongation of these normal faults, in agreement with the tectonics of the Caviahue caldera. Then, the two nearby seismic clusters reveal both a tectonic origin, with strike-slip focal mechanisms compatible with the Liquiñe-Ofqui Fault System, and a hydrothermal origin with normal focal mechanisms, compatible with the hydrothermal system of the Copahue active volcano.

In this work we have analyzed the results of temporal geodetic variations associated with tectonic deformation on the Andean backarc in southern San Juan province, Argentina. This area is affected by the subduction of the Juan Fernández Ridge and has the greatest seismic hazard in Argentina. Since 2000, we have monitored the variations of gravity annually with high precision (g4D) in the active deformation belt, around the city of San Juan (31°S to 32°S, 68°W to 69°W). Temporal gradients of g4D have been associated with active structures and interpreted as subsurface mass redistributions as a result of accumulation and release of stress. These data, in addition to the topographic deformations measured by the Global Positioning System (GPS) and the identification of structures in the crystalline basement from the geophysical models, allow us interpret mechanisms of deformation in the contact between the Precordillera and Pampean Ranges in the foreland of San Juan. In this area, after more than a decade of low activity, in 2012 the Tulum Fault System (TFS) was reactivated, generating crustal events of moderate magnitude including an earthquake of M w 5.0 (January 18, 2012). According to our interpretation, the fault system accumulated elastic deformation for more than 10 years expressed as height increases at gravity stations (decrease of g4D) until the year 2011. The January 18, 2012 earthquake released part of the energy at the same time as a coseismic increase of g4D. This should be reflected in regional tectonic subsidence from the point of view of conventional gravimetric models. However, GPS reoccupation of the benchmarks located in this fault system indicates a generalized increase in altitude of the fault system in the last 15 years. TFS behavior could be assumed as topographic flexural displacements induced by a system of blind faults. We analyzed the time series of a permanent Global Navigation Satellite System (GNSS) station located to the north of the TFS. The GRLS station (31.61ºS; 68.32ºW) presents slow variation in the vertical and north components. The variation began on December 20, 2011 reaching its maximum amplitude on January 18, 2012. The geodetic variations coincide with the period of seismic reactivation. Fil: Leiva, Maria Flavia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ruiz, Francisco. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Acosta, Gemma. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Nacif Suvire, Silvina Valeria. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Nacif, Andres Antonio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Christiansen, Rodolfo Omar. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sisterna, Jorge Alberto. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Figueroa Berroca, Mara Anabel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

We integrate field and wellbore data to discuss the stress field in the frontal sector of the Malargüe fold-and-thrust belt (Andes of Argentina). Surface observations indicate N-S thrusts and NW to WNW and ESE strike-slip faults are active in the study area. Inversion of fault kinematic indicators, combined with borehole breakout data and a mini-frac test within the study area, constrain the Quaternary to recent stress state, which is characterized by a subhorizontal, E-W oriented maximum stress, and by intermediate and minimum stresses with similar magnitudes that are locally interchanged, producing a setting in which reverse and strike-slip faults are alternatively active. The implications of the recognized structures for earthquake hazard are examined. Fil: Mescua, Jose Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Barrionuevo, Matías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Suriano, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Stahlschmidt, E.. El Trébol S.a.; Argentina Fil: de la Cal, H.. Roch S.a.; Argentina Fil: Soto, J. L.. Roch S.a.; Argentina Fil: Mazzitelli, Manuela Amelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

Only few (six) focal mechanism, in CMT Catalog, have been so far known for intraplate shallow events in the Andean chain close to Chile–Argentina state border at latitudes ∼35° S. We add two more mechanisms, depths and moment magnitudes by carefully analyzing full waveforms of weak events recorded by broad-band stations of the Chile Argentina Geophysical Experiment (southern profile). The moment magnitudes of both events (Mw = 3.6 and 3.7) are lower than the duration magnitudes (Md = 4.0 and 4.29) reported by NEIC. The source depth, constrained by waveforms for one of the studied events (5.5–8.5 km) seems to be considerably shallower than the hypocenter depth located by means of arrival times (∼20 km). The waveform analysis was complemented by first-motion polarities which resulted in an uncertainty assessment of the focal mechanism. Event 1 (2001-11-03) has a strike-slip mechanism with a small normal component and almost vertical nodal planes in the north-south and east-west directions. The north-south nodal plane could be related to the Calabozos faults system. Event 2 (2002-02-16) has a strike-slip mechanism with a small thrust component. The latter event (its subhorizontal nodal plane) could be associated with the El Diablo-El Fierro fault system. Dextral strike-slip solutions are consistent with recent studies in the area.

In order to understand the response of the stress field state to intrinsic processes during the construction of the Andes, such as thickening of the continental crust, lithospheric delamination, and/or thermal weakening, we investigate the stress field evolution of the arc region since the last 20 my, in the Central Andes (22°-26.5°S). The 43 reduced paleostress tensors derived from inversion of 682 fault-slip data reveal a complex pattern of stress states during the last episode of orogenic construction and topographic uplift. We identify two geodynamic stages; the first stage corresponds to the construction of the Altiplano/Puna plateau and the second one to its gravitational collapse. Four stress states that have prevailed in the Altiplano/Puna plateau since middle Miocene times, characterize the transition from one stage to the other. Along the study latitudes, a spatiotemporal change in stress state is clearly observed, which led to an understanding that a change in the stress field may be related not only to the boundary conditions but also to intrinsic factors associated with the construction of the Andean orogeny. Our results suggest that ca. 13-10 Ma and ca. 8-5 Ma, in the southern Altiplano and northern Puna, and in the southern Puna, respectively, regional elevation and crustal thicknesses reached threshold values necessary to generate the orogenic collapse.

The Cacheuta sub-basin of the Triassic Cuyo Basin is an example of rift basin inversion contemporaneous to the advance of the Andean thrust front, during the Plio–Quaternary. This basin is one of the most important sedimentary basins in a much larger Triassic NNW-trending depositional system along the southwestern margin of the Pangea supercontinent. The amount and structural style of inversion is provided in this paper by a three-dimensional approach to the relationship between inversion of rift-related structures and spatial variations in late Cenozoic stress fields. The Plio–Quaternary stress field exhibits important N–S variations in the foreland area of the southern Central Andes, between 33 and 34° S, with a southward gradual change from pure compression, with σ1 and σ2 being horizontal, to a strike-slip type stress field, with σ2 being vertical. We present a 3-D approach for studying the tectonic inversion of the sub-basin master fault associated with strike-slip–reverse to strike-slip faulting stress regimes. We suggest that the inversion of Triassic extensional structures, striking NNW to WNW, occurred during the Plio–Pleistocene in those areas with strike-slip–reverse to strike-slip faulting stress regime, while in the reverse faulting stress regime domain they remain fossilized. Our example demonstrates the impact of the stress regime on the reactivation pattern along the faults.

An Mw 8.2 earthquake affected on September 8, 2017 the Cocos plate beneath the Caribbean plate next to the transform contact with the North American plate across the Tehuantepec gap, one of the two gaps that exist along the Mexican subduction zone offshore Chiapas. The epicenter occurred at a depth of 47 km and was associated with a highly steep normal fault parallel to the trench. The origin can be related to slab pull forces, dehydration processes and reactivation of outer rise faults. This earthquake produced positive changes in the Coulomb static stress, which would favor the development of thrust displacements along the interplate contact across the Tehuantepec gap instead of liberating tensions accumulated on it for decades. In the case that stresses were not released steadily in the future, a thrusting-related event with a magnitude of Mw 7.9 or higher could be expected after the September 8, 2017 Chiapas earthquake. However, the differential weight of the forearc offshore (that contains a region with a high positive gravity gradient) could inhibit rupture propagation to the coast precluding higher magnitudes. Combined and satellite only earth gravity field models show a highly heterogeneous density structure along the forearc of the North America-Caribbean plates and in particular at the studied zone. Maximum displacements in the rupture zone correlate to minimum gravity-derived anomalies showing a probable relationship between the differential weight of the forearc structure and the extensional faulting affecting the bending of the Cocos plate at depth. In this sense, variable sediment thicknesses over the forearc, and a high gravity gradient zone parallel to the trench in the outer forearc, could be reflecting physical heterogeneities that influence the propagation of the rupture zone. Additionally, to the north, a highly positive gradient signal related to the subducted Tehuantepec Fz projection beneath the North American plate marks the ending of the main slip patch acting as a barrier to the seismic rupture propagation. This event exemplifies (1) how extensional ruptures in the downgoing slab of a subduction zone can increment accumulated elastic strain across a seismic gap instead of liberating tensions, (2) that rupture propagation for this intraplate event was probably controlled (at shallow depths) by the density structure of the forearc, similarly to recent interplate earthquakes along the Chilean margin; (3) how a low gravity gradient signal and low density structures identified from the inversion model in the region of the outer forearc, where the normal stress increased after the main seismic event, suggest a higher risk of occurrence of a great megathrust earthquake. Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; Argentina Fil: Alvarez Pontoriero, Orlando. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina Fil: 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"; Argentina

We localized crustal earthquakes in the Andean arc, between 35°S and 36°S, from December 2009 to May 2010. This research shows a seismicity increase, in a narrow longitudinal area, of more than nine times after the great Mw 8.8 Maule earthquake. The localized seismicity defines an area of 80 km long and 18 km wide and NNW to NNE trend. The Md magnitudes varied from 0.7 to 3.1 except for two earthquakes with Mw of 3.9 and 4.5, located in the northern end of the area. The focal mechanisms for these two last events were normal/strike-slip and strike-slip respectively.During 2011, a network of 13 temporary stations was installed in the trasarc region in Malargüe, Argentina. Sixty earthquakes were localized in the study region during an 8 month period. We explored how changes in Coulomb conditions associated with the mega-thrust earthquake triggered subsequent upper-plate events in the arc region. We assumed the major proposed structures as receiver faults and used previously published earthquake source parameters and slip distribution for the Maule quake. The largest contribution to static stress change, up to 5 bars, derives from unclamping resulting consistent with co-seismic dilatational deformation inferred from GPS observations in the region and subsidence in nearby volcanoes caused by magma migration.Three different Quaternary tectonic settings; extensional, strike-slip and compressional- have been proposed for the arc region at these latitudes. We found that the unclamping produced by the Maule quake could temporarily change the local regime to normal/strike-slip, or at least it would favour the activation of Quaternary NNE to N-trending dextral strike-slip faults with dextral transtensional movement. Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Triep, Enrique Gaudencio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Lupari, Marianela Nadia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina

Data from 45 seismological stations mostly temporary were used to obtain an accurate data set of intraslab seismicity of the Nazca subducted plate between 33°S to 35°S. The interest zone located in the transition section where the Nazca plate changes from flat slab north of ~ 33° to normal slab south of that latitude. In addition, the study region is located where the active volcanic arc appears. From a set of earthquakes which were relocated using a grid-search multiple events algorithm we obtained the plate geometry from latitudes of 33°S to 34.5°S and from 60 km to 120 km in depth. The obtained morphology shows notable similarity in its structure to Maipo Orocline revealing some possible strong connection between the overriding plate and the subducting plate. We suggest that the subducted plate at the trench has been deformed in its shape consistently with the Maipo Orocline pattern and its deformation is observed below the interface zone. Our results are consistent with van Keken et al 2011 models, and based on this the seismicity located between 70-120 km is probably related with dehydration processes rather than mechanical processes. From our precise earthquake locations we observed a complete lack of intraslab seismicity below 120 km depth. This valuable finding can be used to better constrain thermal models for the subduction region of Central Chile. Fil: Nacif Suvire, Silvina Valeria. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Triep, Enrique Gaudencio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Spagnotto, Silvana Liz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina Fil: Aragon, Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina Fil: Furlani, Renzo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Alvarez Pontoriero, Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina

Between 33°-36°S, the Nazca plate subducts below South American plate with an angle of ~30°, and it is seismically active until ~200-280km depth. At 33.5°S, the seismicity decreases drastically at 120km depth, just below the volcanic arc. In this paper, we studied a pair of associated earthquakes located in the area where the frequency of seismicity changes. The hypocenters of the Mw=6.4, June 16th, 2000 and Mw=5.7 January 7th, 2003 earthquakes were found nearby, adjacent to the oceanic Moho, closely associated with each other. The slip on the plane of the 2000 event produced Coulomb stress changes on the fault plane of 2003, both westward dipping, with a variation from ~1bar near the hypocenter of the latter to ~0.1bars in the deepest part of the plane. The two earthquakes combined process describes a normal focal mechanism, which cuts through the crust and breaks the mantle, reaching depths of ~40km below the Moho.The composed fault plane of the 2000 and 2003 events corresponds to a west-dipping normal fault with strike and dip consistent with those of the outer ridge faults. Thus, these events could be related to a preexisting fault originated in that environment reactivated at depth.The slip on the composed fault plane is consistent with the bending produced by the slab pull. Dehydration could be associated to these events. Fil: Spagnotto, Silvana Liz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina Fil: Triep, Enrique Gaudencio. Universidad Nacional de San Juan; Argentina Fil: Giambiagi, Laura Beatriz. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Nacif Suvire, Silvina Valeria. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Alvarez Pontoriero, Orlando. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Earthquakes with magnitudes M 3.5 and depths between 15km and 35km were registered in the Andes backarc between 32.5°S and 33.75°S within a temporary experiment from November 2002 to March 2003. A band trending NW-NNW of normal focal mechanism earthquakes is located just by the thrust front towards west, and cover the southern tip of the Southern Precordillera and the western side of the Cerrilladas Pedemontanas, Mendoza Province, Argentina. The short temporal experiment precludes firm interpretations about the existence of this confined tensional stress field within the regional predominant compressional stress field. Probably it is related to a temporary stress relaxation. The normal earthquakes are likely associated to normal faults, and/or to its subsidiaries, that were inverted by contraction and now re-inverted at least transitorily as normal. These faults, which are near and to the East of the suture between Chilenia and Cuyania Paleozoic terranes, were originally involved in the Cuyo Triassic basin formation. Fil: Nacif Suvire, Silvina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Triep, Enrique. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina Fil: Furlani, Renzo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis. Facultad de Cs.fisico Matematicas y Naturales. Departamento de Fisica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis; Argentina

Considerable improvements in the measurement of the Earth gravity field from GOCE satellite mission have provided global gravity field models with homogeneous coverage, high precision and good spatial resolution. In particular, the vertical gravity gradient (Tzz), in comparison to the classic Bouguer anomaly, defines more accurately superficial mass heterogeneities. Moreover, the correction of these satellitederived data from the effect of Earth topographic masses by means of new techniques taking into account the Earth curvature, improves results in regional analyses. In a recent work we found a correlation between Tzz and slip distribution for the 2010 Maule Mw ¼ 8.8 earthquake. In the present work, we derive the vertical gravity gradient from the last GOCE only model, corrected by the topographic effect and also by the sediments on depocenters of the offshore region at the PerueChile margin, in order to study a spatial relationship between different lobes of the gravity derived signal and the seismic sources of large megathrust earthquakes. In particular, we analyze this relation for the slip models of the 1996 Mw ¼ 7.7 Nazca, 2001 Mw ¼ 8.4 Arequipa, 2007 Mw ¼ 8.0 Pisco events and for the slip models of the 2014 Mw ¼ 8.2 Pisagua and Mw ¼ 7.7 Iquique earthquakes from Schurr et al. (2014), including the previously analyzed 2010 Mw ¼ 8.8 Maule event. Then we find a good correlation between vertical gravity gradients and main rupture zones, correlation that becomes even stronger as the event magnitude increases. Besides this, a gravity fall in the gravity gradient was noticed over the area of the main slip patches at least for the two years before 2014 Mw ¼ 8.2 Pisagua and Mw ¼ 7.7 Iquique earthquakes. Additionally, we found temporal variations of the gravity field after 2010 Mw ¼ 8.8 Maule event, related to the main patches of the slip distribution, and coseismic deformation. Therefore, we analyzed vertical gravity gradient field variations as an indirect measure of the variable seismic coupling finding a potential relationship between Tzz and the seismic b-value. These relationships exemplify the strong potential of the satellite only derived models as a predictive tool to determine potential seismic energy released in a subduction segment, determining the potential size of a potential rupture zone, and in particular internal slip distribution that allows inferring coseismic displacement field at surface. Fil: Alvarez Pontoriero, Orlando. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Nacif Suvire, Silvina Valeria. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: 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 ; Argentina Fil: Gimenez, Mario Ernesto. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Chlieh, Mohamed. Observatoire de la Cote D'Azur; Francia Fil: Braitenberg, Carla. Universita Degli Studi Di Trieste; Italia

This review explores the complex interactions of endogenic and exogenic processes in the segment of the Andes that straddle a transition from the Pampean flat slab to a normal subduction segment (32°–36°S). This segment shows remarkable along-strike variations in topographic uplift, structural elevation, amount and rate of shortening, and crustal root geometry. In the flat-slab segment, high elevations, the development of several tectonic provinces (mountain systems) and the lack of active volcanism characterize the orogen. Deformation and uplift advanced to the east, together with arc-related magmatic activity, sequentially uplifting the Principal Cordillera (20 to ~8 Ma), the Frontal Cordillera (12–5 Ma), the Precordillera (

Satellite-only gravity measurements and those integrated with terrestrial observations provide global gravity field models of unprecedented precision and spatial resolution, allowing the analysis of the litho- spheric structure. We used the model EGM2008 (Earth Gravitational Model) to calculate the gravity anomaly and the vertical gravity gradient in the South Central Andes region, correcting these quantities by the topographic effect. Both quantities show a spatial relationship between the projected subduc- tion of the Copiapó aseismic ridge (located at about 27◦ ?30◦ S), its potential deformational effects in the overriding plate, and the Ojos del Salado-San Buenaventura volcanic lineament. This volcanic lineament constitutes a projection of the volcanic arc toward the retroarc zone, whose origin and development were not clearly understood. The analysis of the gravity anomalies, at the extrapolated zone of the Copiapó ridge beneath the continent, shows a change in the general NNE-trend of the Andean structures to an ENE-direction coincident with the area of the Ojos del Salado-San Buenaventura volcanic lineament. This anomalous pattern over the upper plate is interpreted to be linked with the subduction of the Copiapó ridge.We explore the relation between deformational effects and volcanism at the northern Chilean-Pampean flat slab and the collision of the Copiapó ridge, on the basis of the Moho geometry and elastic thicknesses calculated from the new satellite GOCE data. Neotectonic deformations interpreted in previous works associated with volcanic eruptions along the Ojos del Salado-San Buenaventura volcanic lineament is interpreted as caused by crustal doming, imprinted by the subduction of the Copiapó ridge, evidenced by crustal thickening at the sites of ridge inception along the trench.Finally, we propose that the Copiapó ridge could have controlled the northern edge of the Chilean-Pampean flat slab, due to higher buoyancy, similarly to the control that the Juan Fernandez ridge exerts in the geometry of the flat slab further south. Fil: Alvarez Pontoriero, Orlando. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gimenez, Mario Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Folguera Telichevsky, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos ; Argentina Fil: Spagnotto, Silvana Liz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina Fil: Bustos, Emilce. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; Argentina Fil: Baez, Walter Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; Argentina Fil: Braitenberg, Carla. Universita Degli Studi Di Trieste. Facolta Di Scienze Matematiche. Fisiche E Naturali. Dipartimento Di Geoscienze; Italia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

El actual frente orogénico activo de los Andes Centrales abarca parte del piedemonte mendocino ubicado cerca de la ciudad capital donde habitan al menos 800.000 personas. A pesar de ello, se carece de un estudio integral de fallas activas de este sector como potenciales fuentes sismogénicas. El presente estudio intenta soslayar esta falencia caracterizando las principales estructuras activas e integrándolas en un modelo cinemático-estructural elaborado a partir de tres perfiles estructurales balanceados. La deformación pedemontana se caracteriza por una población de fallas compresivas de rumbo N-S a NNE-SSO, cuyo nivel de despegue se ubicaría en el basamento pre-Silúrico, constituyendo un frente emergente de piel gruesa. La serie de corrimientos imbricados con despegue ubicado a 10-11 km de profundidad corresponde a las fallas Melocotón y Divisadero Largo, que presentan expresión superficial, y a una falla ciega denominada Maure, interpretada a partir del modelo estructural. La falla ciega Maure transfiere su rechazo hacia un sistema de fallas retrovergentes de piel fina, con despegue dentro de los depósitos sinorogénicos neógenos, conformando de esta manera una zona de deformación triangular. Según los rasgos morfométricos de estos fallamientos los sismos máximos probables rondan entre magnitudes de 5.4 a 6.8 Mw. Co-existen fallas transcurrentes sinestrales de rumbo NO-SE que se encuentran cortando a las fallas retrovergentes del sistema Cerro de la Gloria. Los resultados obtenidos fueron contrastados con datos de subsuelo y resolución de mecanismos focales de sismos locales superficiales. Current active front of the Central Andes comprises part of the western piedmont of the city of Mendoza, where more than 800,000 people are established. Despite this, a comprehensive study of active faults mainly as potential seismogenic sources is lacking in this crucial sector of the Andean foreland. The present study attempts to outwit this shortcoming by characterizing the main Quaternary structures and integrating them in a structural-kinematic model developed from three balanced structural cross-sections. The foreland deformation at the study area is characterized by a population of N-S to NNE striking reverse faults, whose detachment level will be located in the Pre Silurian basement, constituting a thick skin thrust front. The series of thrusts, rooted at a 10-11 km-depth detachment, corresponds to Melocotón and Divisadero Largo faults showing surficial expression, and a blind fault called Maure, inferred om the structural-kinematic model. The Maure blind fault transfers shortening to the west-vergent thin-skinned Cerro de la Gloria thrusts, thus forming a triangular deformation zone. According to morphometric features of these active faults, a probable maximum earthquake magnitude ranges from Mw 5.4 to 6.8. Furthermore, strike slip faults with NW-SE strike are cutting Cerro de la Gloria fault system. Results were contrasted with ground data and focal mechanisms of surficial local earthquakes. Fil: Moreiras, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Spagnotto, Silvana Liz. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Nacif Suvire, Silvina Valeria. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Mescua, Jose Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Toural Dapoza, Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

We propose an integrated kinematic model with mechanical constrains of the Maipo-Tunuyán transect (33°40'S) across the Andes. The model describes the relation between horizontal shortening, uplift, crustal thickening and activity of the magmatic arc, while accounting for the main deep processes that have shaped the Andes since Early Miocene time. We construct a conceptual model of the mechanical interplay between deep and shallow deformational processes, which considers a locked subduction interface cyclically released during megathrust earthquakes. During the coupling phase, long-term deformation is confined to the thermally and mechanically weakened Andean strip, where plastic deformation is achieved by movement along a main décollement located at the base of the upper brittle crust. The model proposes a passive surface uplift in the Coastal Range as the master décollement decreases its slip eastwards, transferring shortening to a broad area above a theoretical point S where the master detachment touches the Moho horizon. When the crustal root achieves its actual thickness of 50 km between 12 and 10 Ma, it resists further thickening and gravity-driven forces and thrusting shifts eastwards into the lowlands achieving a total Miocene-Holocene shortening of 71 km. Fil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Tassara Oddo, Andres Humberto. Universidad de Concepción; Chile Fil: Mescua, Jose Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Tunik, Maisa Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Negro; Argentina Fil: Alvarez, Pamela P.. Tehema S.A; Chile Fil: Godoy, Estanislao. Consultant; Chile Fil: Hoke, Greg. Syracuse University; Estados Unidos Fil: Pinto, Luisa. Universidad de Chile; Chile Fil: Spagnotto, Silvana Liz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina Fil: Porras, Hernan. Syracuse University; Estados Unidos Fil: Tapia, Felipe. Syracuse University; Estados Unidos Fil: Jara, Pamela. Universidad de Santiago de Chile; Chile Fil: Bechis, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio. Universidad Nacional de Río Negro. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio; Argentina Fil: Garcia, Victor Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Negro; Argentina Fil: Suriano, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Geológicas; Argentina Fil: Moreiras, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Pagano Género, Diego Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

En el presente trabajo, a partir de datos gravimétricos terrestres, se preparó una carta de anomalías de Bouguer, la cual fue adecuadamente filtrada a fin de separar efectos gravimétricos someros y profundos. Con base en un modelo de densidad, mediante de técnicas de inversión gravimétrica, se modeló la discontinuidad corteza-manto y el basamento cristalino, respectivamente. De forma posterior, se evaluó el espesor elástico equivalente considerando la información de la discontinuidad de la corteza-manto y la carga topográfica. Se encontraron valores altos de espesor elástico Te, al este de la precordillera Andina y al oeste de la sierra Pampeana de Velasco. Estos resultados son consistentes con los valores positivos de anomalía residual de Bouguer e isotáticos, lo que estaría indicando la presencia de rocas de alta densidad en corteza media a superior. Además, los análisis petrográficos y geoquímicos realizados en afloramientos en superficie indican un origen mantélico. Fil: Weidmann, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Spagnotto, Silvana Liz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; Argentina Fil: Gimenez, Mario Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina Fil: Martinez, Myriam Patricia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto Geofisico Sismologico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Alvarez Pontoriero, Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Sanchez, Marcos Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina Fil: Lince Klinger, Federico Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina