Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes
The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we...
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ftchinacadscimhe:oai:ir.imde.ac.cn:131551/44734 2023-05-15T16:40:42+02:00 Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes 2017-01-01 http://ir.imde.ac.cn/handle/131551/44734 英语 eng Journal of Mountain Science http://ir.imde.ac.cn/handle/131551/44734 Glacial Morphology Sierra Baguales Ice Sheet Glaciations Alpine Glaciations Middle Holocene 期刊论文 2017 ftchinacadscimhe 2022-12-19T18:25:47Z The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range (SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field (SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift, which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum (LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower elevations. This can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26 m Equilibrium Line Altitude (ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio (AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography. Report Ice Sheet IMHE OpenIR (Institute of Mountain Hazards and Environment, Chinese Academy of Sciences) Ela ENVELOPE(9.642,9.642,63.170,63.170) Pacific |
institution |
Open Polar |
collection |
IMHE OpenIR (Institute of Mountain Hazards and Environment, Chinese Academy of Sciences) |
op_collection_id |
ftchinacadscimhe |
language |
English |
topic |
Glacial Morphology Sierra Baguales Ice Sheet Glaciations Alpine Glaciations Middle Holocene |
spellingShingle |
Glacial Morphology Sierra Baguales Ice Sheet Glaciations Alpine Glaciations Middle Holocene Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes |
topic_facet |
Glacial Morphology Sierra Baguales Ice Sheet Glaciations Alpine Glaciations Middle Holocene |
description |
The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range (SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field (SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift, which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum (LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower elevations. This can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26 m Equilibrium Line Altitude (ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio (AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography. |
format |
Report |
title |
Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes |
title_short |
Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes |
title_full |
Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes |
title_fullStr |
Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes |
title_full_unstemmed |
Relict glacial landscape in the Sierra Baguales Mountain Range (50°-51° S): evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes |
title_sort |
relict glacial landscape in the sierra baguales mountain range (50°-51° s): evidence of glaciation dynamics and types in the eastern foothills of the southern patagonian andes |
publishDate |
2017 |
url |
http://ir.imde.ac.cn/handle/131551/44734 |
long_lat |
ENVELOPE(9.642,9.642,63.170,63.170) |
geographic |
Ela Pacific |
geographic_facet |
Ela Pacific |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
Journal of Mountain Science http://ir.imde.ac.cn/handle/131551/44734 |
_version_ |
1766031114514726912 |