Glaciation of the central part of the Sør Rondane, Antarctica: glaciological evidence

• Main Authors: Pattyn, F., Decleir, H., Huybrechts, P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1992
• Subjects: Jenningsbreen; Sør Rondane Mountains; Sør-Rondane; Antarc*; Antarctica
• Online Access: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=199756

Ice thickness measurements, carried out by radio echo sounder and gravimeter in the central part of the Sør Rondane Mountains, reveal a subglacial topography of the outlet glaciers and its tributaries characterized by U-shaped valley profiles and overdeepened bedrock. Mass-flux measurements highlight the reduced flow of at least one glacier (Jenningsbreen). This glacier is in the process of being cut off from the main ice supply and may serve as an example for the deglaciation process. An interesting feature of this deglaciation is that, once decoupled from the main ice supply, this glacier is probably characterized by an increased lowering of the ice surface gradient due to the ablation which is characteristic for the upper part of the present outlet glacier. In the end this will result in a southward flow of which examples can be found elsewhere in the mountains. On the basis of the field evidence a numerical flow line model is presented to simulate the behaviour of the outlet glaciers of the central part of the mountains during the last glacial maximum. These experiments show an increase of 300-400 m in ice thickness under realistic assumptions for mass balance, temperature and sea level. Some of the higher glacial levels are then attributed to an environment characterized by a higher accumulation predating the last glacial maximum.