| Summary: | We compiled a geomorphological map and a reconstruction map of glacier extension and ice-free areas in the Martel Inlet, located in King George Island, South Shetlands, Antarctica. Glacier extension data were derived from a digitized orthophotomosaic (2003), SPOT (February, 1988; March, 1995 and 2000), Quickbird (October, 2006) and Cosmo-Skymed (February, 2011) images. This mapping was supported by field data collection carried out in the summers of 2007, 2010 and 2011, and by topographic surveys and geomorphological mapping of proglacial area. Several types of glacial deposits were identified in the study area, such as frontal and lateral moraines, flutes, meltwater channels and erosional features like rock moutonnées, striations and U-shaped valleys. These features allowed reconstructing the evolution of the deglaciation environment in the Martel Inlet ice-free areas, which has been affected by a regional climate warming trend. The mapped data indicated the glaciers in study area lost about 6.64 km² of their ice masses (13.2% of the total area), without any advances during 1979-2011. Since those years these glaciers receded by an average of 0.25 km a⁻¹. These ice-free areas were susceptible to rapid post-depositional changes. Este estudo apresenta o mapa geomorfológico e mapa de reconstrução da extensão das geleiras e áreas sem cobertura de gelo na Enseada Martel, localizada na ilha Rei George, Shetlands do Sul, Antártica. Os dados das áreas das geleiras foram obtidos através de um ortofotomosaico gerado (2003), imagens SPOT (Fevereiro de 1988; Março de 1995 e 2000), Quickbird (Outubro de 2006) e Cosmo-SkyMed (Fevereiro de 2011). Este mapa foi baseado em dados de campo obtidos nos verões de 2007, 2010 e 2011, e pelos dados topográficos e mapa geomorfológico gerado neste estudo. Diversos tipos de depósitos glaciais foram identificados na área de estudos, tais como morainas laterais e frontais, flutings, canais de água de degelo e feições erosivas tais como rochas moutonnées e vales em forma de U. Estas ...
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