Geomorphological processes and frozen ground conditions in Elephant Point (Livingston Island, South Shetland Islands, Antarctica)

• Autor(a) principal: Oliva, Marc
• Data de Publicação: 2017
• Outros Autores: Ruiz-Fernández, Jesús
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Texto Completo: http://hdl.handle.net/10451/36212
• topic: Elephant Point; Maritime Antarctica; Geomorphology; Frozen ground; Permafrost

Elephant Point is an ice-free area in the SW corner of Livingston Island (Maritime Antarctica). The retreat of Rotch Dome glacier during the Holocene has exposed a land area of 1.16 km2 . Up to 17.3% of this surface has become ice-free between 1956 and 2010. A detailed geomorphological mapping of this ice-free environment was conducted in late January 2014. A wide range of active periglacial landforms show that periglacial processes are widespread. From the glacier to the coast four different geomorphological areas are identified: proglacial environment, moraine complex, bedrock plateaus and marine terraces. In situ measurements of the thawed soil depth show evidence of the widespread frozen ground conditions in the area. Field observations of permafrost exposures suggest that these frost conditions may be related to a soil permafrost regime, almost down to sea level. The activity of penguin colonies and elephant seals has created minor geomorphological features in the raised marine terraces. Here, several archaeological sites related to early human colonization of Antarctica were also found in natural shelters.