Reconstructing the History of Reedy Glacier, Antarctica

• Main Author: Bromley, Gordon R.M.
• Format: Text
• Language: unknown
• Published: DigitalCommons@UMaine 2005
• Subjects: Reedy Glacier (Antarctica); Glaciers; Earth Sciences; Glaciology; Antarc*; Antarctic; Antarctica; Ice Sheet; Reedy Glacier; Ross Sea
• Online Access: https://digitalcommons.library.umaine.edu/etd/1187; https://digitalcommons.library.umaine.edu/context/etd/article/2181/viewcontent/BromleyGRM2005.pdf

This thesis describes the distribution and sedimentologic characteristics of glacial deposits at Reedy Glacier (86"s) in the southern Transantarctic Mountains. Reedy Glacier is an outlet glacier of the East Antarctic Ice Sheet which flows into the West Antarctic Ice Sheet ~100 km behind the Ross Sea grounding line. This position means the flow and thickness of Reedy Glacier are controlled, in part, by the damming effect of the West Antarctic Ice Sheet. This thesis is an integral part of a larger study aimed at assessing the current stability of the West Antarctic Ice Sheet through recent changes in the surface of Reedy Glacier. Glacial geologic mapping and 10Be surface-exposure dating provide a record of glaciation at Reedy Glacier spanning the last ~290 Ma. The earliest glacial landforms were deposited when the Antarctic climate was still temperate. Since the inception of cold polar conditions, Reedy Glacier has expanded on at least six occasions. Each expansion has been less extensive than the previous, suggesting changes in the size of the West Antarctic Ice Sheet and perhaps downcutting of the bed of Reedy Glacier. The most recent of these episodes occurred during the Late Pleistocene and is contemporary with the Last Glacial Maximum throughout the Transantarctic Mountains. At this time, the ice sheet was as much as 500 m thicker than it is today. Subsequent deglaciation of Reedy Glacier has been controlled by recession of the Ross Sea grounding line and has lagged the onset of global deglaciation by several millennia.