|
|
The dynamics of the north-western Laurentide Ice Sheet margin
Stoker, Benjamin James ; Margold, Martin (advisor) ; Darvill, Christopher (referee) ; Nývlt, Daniel (referee)
The Laurentide Ice Sheet (LIS) was the largest ephemeral ice sheet in the Northern Hemisphere, reaching its all-time maximum during the last glacial cycle (~115 ka to ~11.7 ka) as it coalesced with the Cordilleran and Innuitian ice sheets over northern North America and the Canadian Arctic Archipelago. At its maximum extent it was comparable in size to the modern-day Antarctic Ice Sheet and may provide a useful analogue for understanding the long-term dynamics of ice sheets. There are considerable regional variations in our understanding of the deglaciation of the LIS. In particular, the northwestern LIS remains one of the most poorly understood sectors, as the latest reconstruction of this sector dates to the early 1990s and empirical constraints on the timing of deglaciation are sparse. In this thesis, I reconstruct the deglaciation of the northwestern LIS from its local Last Glacial Maximum (LGM) position using numerical dating methods and glacial geomorphological mapping. I use a combination of high-resolution digital elevation models (DEMs) and satellite imagery to map the glacial geomorphology of much of the Northwest Territories, Canada, and reconstruct the ice margin retreat patterns, ice flow dynamics, and interaction of the northwestern LIS with other ice masses. This new information is...
|
guest ::
