SciELO - Scientific Electronic Library Online

vol.62 número4Cambios en lagos y circulación fluvial vinculados al calentamiento climático del Pleistoceno tardío-Holoceno temprano en Patagonia e isla 25 de mayo, islas Shetland del Sur, AntártidaModelos de cinemática de placas para Antártida durante la ruptura de Gondwana: una revisión índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados




  • Não possue artigos citadosCitado por SciELO

Links relacionados

  • Não possue artigos similaresSimilares em SciELO


Revista de la Asociación Geológica Argentina

versão impressa ISSN 0004-4822versão On-line ISSN 1851-8249


STRELIN, J.A. et al. Genetic peculiarities of the rock glaciers in the James Ross Island, Antarctic Peninsula. Rev. Asoc. Geol. Argent. [online]. 2007, vol.62, n.4, pp.627-634. ISSN 0004-4822.

Rock glaciers are considered amongst the most conspicuous landforms of James Ross Island. Their formation follows the convergence of a series of morphostructural and morphogenetic environmental conditions. The most important morphostructural condition is the presence of basaltic mesas that provide the raw material for the debris cover of the rock glaciers. The morphogenetic conditions involve small polithermal glaciers that due to little summer temperature variations, subtle reduction in the precipitations, and/or changes in the intensity and direction of the main regional winds, become debris covered. An important factor related to the debris cover, particularly to the nearly homogenous debris distribution over the whole glacier surface, is related to the so called oscillation of the regelation front. Under stable climatic conditions, after the debris cover reaches a thickness similar to that of the active layer, the ice core ablation diminishes markedly, remaining only the own plastic deformation of the ice core. The debris cover of the rock glaciers studied in James Ross Island reaches around 0.3 m in thickness close to the valley head, increasing the thickness to more than 1 m in the fronts. The ice cores rarely exceed 80 m in thickness, and close to the central part of the rock glacier the horizontal flow velocity amounts about 0.15 m per year. The formation of these rock glaciers, and some ice cored moraines, goes back to the climatic change that finished the Little Ice Age. The severe climatic warming verified in the last 15 years in the northern sector of Antarctic Peninsula accelerated the collapse of some of these landforms.

Palavras-chave : Climatic change; Rock glaciers; Tumbledown; Lachman.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )


Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons