CGRG Bibliography of Canadian Geomorphology
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Author : Chutko, K.J.; and Lamoureux, S
Date : 2004.
Title : Estimating glacier mass balance from proglacial lacustrine sediments, Colin Archer Peninsula, Devon Island: Preliminary investigations and results.
Publication : Arctic Net. First Annual Scientific Meeting, Palace Royal, Quebec City. December 5-8, 2004. Program.
Issue :
Page(s) : 24.
Abstract
Sedimentary records from proglacial lakes will be used to reconstruct the glacial mass balance of ice caps on the Colin Archer Peninsula, Devon Island. A number of different lake settings (e.g., ice proximal, ice distal, nival) will be employed to quantify glacial mass balance with proglacial lacustrine varves . Depending on the specific lake setting, differing runoff and sediment transport regimes will dominate. For example, an ice proximal lake will be dominated by glacial melt, while a nival lake will experience an entirely nival melt regime. Ice distal lakes will experience a combination of these two regimes. The sedimentary structures are expected to reflect these differing melt regimes, and from the analyses of these structures a model will be developed to determine the relative contributions of nival and glacial melt on an annual basis. The proposed model will employ the two dominant sources of meltwater in the area: glacial and nival melt. Glacial melt is derived from the ablation of the ice caps while nival melt is derived from snowmelt in the basin. Along with the differing sources of meltwater, sediment sources are different for the two processes. Sediment derived from nival melt will be dominated by subaerially-weathered particles and will be transported earlier in the melt season. Sediment derived from glacial melt will likely include large quantities of fine, angular particles such as glacial flour, and will be transported later in the melt season. In the lacustrine sedimentary record, the grain characteristics and the difference in relative timing will be differentiated. Identifying and quantifying the separate melt regimes in the sedimentary record will lead to estimates of glacial mass balance, with nival melt representing winter balance and glacial melt representing summer balance. The Colin Archer Peninsula is located on the northwestern arm of Devon Island, and is approximately 30% glacierized. Based on aerial photography and recent satellite imagery, the ice caps on the peninsula have been identified as among the fastest retreating ice bodies in the Canadian Arctic. This suggests that the region is particularly sensitive to climate change, and the potential for a highresolution record of environmental change is high. A number of lakes have been identified covering the settings described above. In 2003 and 2004, lake sediment cores were recovered from two ice distal lakes. These sediments show a variety of sedimentary structures, and one of the cores is consistently laminated throughout. Thin sections of these sediments are currently being used for detailed sedimentology to develop the varve chronology for the lake.
Bibliography of Canadian Geomorphology