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.

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Temporal distribution of landslides can be verified by means of climatic anomalies linked to the ENSO phenomenon.

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Artículo de publicación ISIIn January and February 2013, heavy rainfall during local summer storms triggered a large number of landslides in the Andes Main and Frontal ranges of central Chile and Argentina (32°–34° S). Most of the mass movements classify as debris flows, while rockfalls and debris avalanches also occurred. The major debris flows occurred in the Maipo and Aconcagua valleys (Chile) and along the Mendoza River valley (Argentina). The debris flows caused serious disruption to the international highway connecting both countries and local roads and produced a large impact on the population of major cities downstream, mainly due to potable water supply cutoffs. Debris flow deposits have silt and clay particles usually ranging between 10 and 20% by weight, which favors the movement of viscous flows in short, steep lateral gullies. Most of the flows tended to channelize, and the materials were deposited in alluvial fans and cones in areas with previous records of such events. This indicates that they constitute a significant hazard that may not have been properly considered in road infrastructure and potable water supply strategies for the region. This potential hazard may become more serious due to climate change in the near future

A GIS-based model framework, designed as a raster module for the Open Source software GRASS, was developed for simulating the mobilization and motion of debris flows triggered by rainfall. Designed for study areas up to few square kilometres, the tool combines deterministic and empirical model components for infiltration and surface runoff, detachment and sediment transport, slope stability, debris flow mobilization, and travel distance and deposition. The model framework was applied to selected study areas along the international road from Mendoza (Argentina) to Central Chile. The input parameters were investigated at the local scale. The model was run for a number of rainfall scenarios and evaluated using field observations and historical archives in combination with meteorological data. The sensitivity of the model to a set of key parameters was tested. The major scope of the paper is to highlight the capabilities of the model-and of this type of models in general-as well as its limitations and possible solutions.

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Abstract. Main aim of this work is to explore the suitability of high resolution SAR images for measuring ice flow velocity within glaciers. Available techniques for this purpose are Differential SAR Interferometry (DInSAR) and Offset Tracking. The former, although theoretically much more precise, is frequently limited by coherence loss (or lacking of coherence) in glacier environment. The latter constitutes an alternative that works well when displacements are large. Study area is the Viedma Glacier (Santa Cruz, Argentina), one of the largest uncovered ice bodies in the South Patagonian Ice (SPI). High resolution COSMO-SkyMed (CSK) acquisitions were processed by estimating range and azimuth offset fields. Useful results, consisting in displacement maps showing areas with different fast-flowing units, were obtained by Offset Tracking processing.