info:eu-repo/semantics/article
Proglacial landform assemblage in a rapidly retreating cirque glacier due to temperature increase since 1970, Fuegian Andes, Argentina
Fecha
2021-10Registro en:
San Martín, Cristina Natalia; Ponce, Juan Federico; Montes, Alejandro; Díaz Balocchi, Luis Alfredo; Gorza, Candela; et al.; Proglacial landform assemblage in a rapidly retreating cirque glacier due to temperature increase since 1970, Fuegian Andes, Argentina; Elsevier Science; Geomorphology; 390; 10-2021; 1-15
0169-555X
CONICET Digital
CONICET
Autor
San Martín, Cristina Natalia
Ponce, Juan Federico
Montes, Alejandro
Díaz Balocchi, Luis Alfredo
Gorza, Candela
Coronato, Andrea Maria Josefa
Resumen
The general trend of glacial retreat since the Little Ice Age has shown an acceleration during the last decades in Southern Argentine and Chilean Patagonia. The Fuegian Andes climatic records report an irregular mean annual temperature increase since 1970, with acceleration from 2015, and the Chato Glacier, as other regional cirque glaciers, has undergone a rapid ice front retreat. A detailed mapping of the proglacial area of the Chato Glacier allowed the identification of a landform assemblage related to the glacier retreat during the last decades. In this paper morphological and sedimentological features of this peculiar landform assemblage, generated in an intense glacial ablation environment, are described and the causes of their origin are discussed. Among the most remarkable landforms annual moraines, hummocky moraines, esker-like landforms, flutes, kettle ponds, dirt cones, glacifluvial deposits, pronival ramparts and collapsed moraines are found. The multitemporal analysis of the Chato Glacier retreat allowed us to interpret that most of these landforms were generated when the landscape became ice-free after 2005. The Chato Glacier cirque floor gentle slope, the thin-ice thickness and the occurrence of a rocky threshold near the glacier front would have promoted the rapid glacier thinning and the disconnection of dead ice. This context, together with the sediments and meltwater availability, would have favored the development of this landform assemblage which is ephemeral due to its high susceptibility to erosion.