Abanicos aluviales telescópicos cuaternarios. Andes argentinos

The largest rivers that drain the Argentine Andean Ranges are characterised by incised valleys in high mountains and by a variety of Quaternary terraces. Their convex-up morphology suggests that these terraces are related to a series of alluvial fans developed where the tributaries join the main riv...

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Detalhes bibliográficos
Autor: Colombo Piñol, Ferrán
Tipo de documento: artigo
Data de publicação:2005
País:España
Recursos:Universidad de Huelva (UHU)
Repositório:Arias Montano. Repositorio Institucional de la Universidad de Huelva
Idioma:espanhol
OAI Identifier:oai:ariasmontano.uhu.es:10272/8685
Acesso em linha:http://hdl.handle.net/10272/8685
Access Level:Acceso aberto
Palavra-chave:Telescopic alluvial fans
Fan dissection
Alluvial terraces
Quaternary
Argentine Andean Ranges
Descrição
Resumo:The largest rivers that drain the Argentine Andean Ranges are characterised by incised valleys in high mountains and by a variety of Quaternary terraces. Their convex-up morphology suggests that these terraces are related to a series of alluvial fans developed where the tributaries join the main river. The succession of alluvial aggradation and degradation is controlled by local base level variation conditioned by temporary lake development in the main river valley. All these factors give rise to the segmented morphology of the fan surface, yielding a telescopic relationship. The variation in the morphology and number of terraces suggests that they are not controlled by a general base level. Neither tectonic activity nor significant climatic changes account for the alluvial fans at the confluence of the tributaries and the main river. Significant variations in rainfall or thunderstorms induced by the El Niño Southern Oscillation (ENSO) could explain the genesis of these telescopic alluvial fans