Lakes and glaciers from Fuegian Andes. Morphology, distribution and origin

CRISTINA SAN MARTÍN; JUAN FEDERICO PONCE; ANDREA CORONATO

Geological resources of Tierra del Fuego

Springer International Publishers

Lugar: Cham; Año: 2021; p. 173 - 188

The intense glacial activity produced in the Fuegian Andes during theQuaternary period generated numerous erosive glacial landforms with abundantdepressions, many of which presently are occupied by glaciers and freshwater lakes.A characterization of these glaciers and lakes is presented based on their geomorphologicaldistribution, morphology and origin. The glaciers in the argentinian sector ofthe Fuegian Andes occupy cirques placed between 880 and 1380 m a.s.l. and are lessthan 1 km2 in area. The lakes are distributed in cirques, glacial valleys, transfluenceglacial surfaces (cols), interdrumlin areas, and on slopes and areas of scouring. Lakesare located between 17 and 1057 m a.s.l. and most of them have an area of less than0.1 km2. The origin of lakes located in lower elevations goes back to glacial retreatafter the Last Glacial Maximum. The lakes in hanging valleys would have developedafter 11,700 yr cal. BP, when the glaciers retreated from moraines corresponding tothe Younger Dryas. Cirque lakes would have been the last to develop. The presenceof Little Ice Age moraines allows us to assign a relative age to some of these lakes. Atpresent, new lakes continue to develop and appear in cirques as the glaciers retreat.These glaciers and lakes of the Fuegian Andes constitute geological resources oftourist and scientific interest, and serve as freshwater reservoirs, lending importanceto their preservation and study.