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Inventario de procesos de remoción en masa en la cuenca baja del Río Blanco, Argentina RMCG | v. 35 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2018.3.787 Jeanneret, P., Moreiras, S.M., 2018, Inventario de procesos de remoción en masa en la cuenca baja del Río Blanco (31°S), Andes Centrales Argentinos: Revista Mexicana de Ciencias Geológicas, v. 35, núm. 3, p. 215-227. RESUMENEste trabajo presenta el primer inventario de los procesos de remoción en masa identificados de la cuenca baja del Río Blanco en la provincia de San Juan, Argentina. La metodología aplicada consistió en la utilización de diferentes sensores remotos para la identificación de los eventos previos a los registros históricos regionales. Los resultados obtenidos en gabinete fueron constatados en terreno verificando la génesis de los depósitos cuaternarios que posteriormente fueron digitalizados en un sistema de información geográfica (QGIS). Mediante un mapeo geomorfológico de detalle, se identificaron cerca de 800 procesos de remoción en masa, los cuales ocupan casi el 30 % del área estudiada, reconociéndose los eventos de caída, flujo, deslizamiento y avalancha de rocas y procesos de soligelifluxión. Estos eventos, casi en su totalidad, presentan sus zonas de arranque por encima de los 3000 m s.n.m. Predominan los eventos activos en ambiente periglacial con claras evidencias de acción glaciar en el pasado. Esto denota un nuevo desafío en el contexto de cambio climático global con tendencia a la degradación del permafrost. ABSTRACTWe introduce the first landslides inventory made in the lower basins of Río Blanco, San Juan province, Argentina. The prehistoric events were recognized through interpretation of diverse satellite images. The obtained results were verified during field trips to terrain and digitalized via a geographical information system (QGIS). After a detailed geomorphological map was made, around 800 mass removal processes were identified, which takes up to 30 % of the study area. The recognized mass removal processes were falls, flows, slides, rock avalanches and soligelifluction. It was also noticed that almost all mapped events and scars are located over the 3000 m a.s.l. The active events tend to be originated in the periglacial environment with evidence of glacier activity in the past. This represents a new challenge in a global warming perspective where permafrost is being degraded.

© 2019 Dúram e Alvarado. Este é um artigo de acesso aberto distribuído sob os termos da Licença Creative Commons Atribuição-Não Comercial-Compartilha Igual (CC BY-NC-SA 4.0), que permite uso, distribuição e reprodução para fins não comercias, com a citação dos autores e da fonte original e sob a mesma licença.

This review paper compiles research related to debris flows and hyperconcentrated flows in the central Andes (30°–33° S), updating the knowledge of these phenomena in this semiarid region. Continuous records of these phenomena are lacking through the Andean region; intense precipitations, sudden snowmelt, increased temperatures on high relief mountain areas, and permafrost degradation are related to violent flow discharges. Documented catastrophic consequences related to these geoclimatic events highlight the need to improve their understanding in order to prepare the Andean communities for this latent danger. An amplified impact is expected not only due to environmental changes potentially linked to climate change but also due to rising exposure linked to urban expansion toward more susceptible or unstable areas. This review highlights as well the need for the implementation of preventive measures to reduce the negative impacts and vulnerability of the Andean communities in the global warming context.