CGRG Bibliography of Canadian Geomorphology
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Author : De Pascale, G.P.; Pollard, W.; and Solomon, S.M.
Date : 2006.
Title : -Resistivity surveys for characterization of coastal permafrost in the Western Canadian Arctic.
Publication : Coastal Zone Canada 2006 Conference and Youth Forum. 14-18 August 2006, Tuktoyaktuk, Northwest Territories.
Issue :
Page(s) :
Abstract
The Western Canadian Arctic is one of the most ice-rich permafrost regions in the world. Defining ice-rich zones can assist in predicting rates of coastal erosion as well as anthropogenic and climate driven thermokarst. Capacitive coupled resistivity (CCR) surveys are a new technique that can aid in the understanding of permafrost and ground ice distribution because of the marked difference in resistivities between unfrozen and frozen sediments as well as ground ice. A better understanding of the geophysical properties of permafrost including ice content will assist in determining variability in ice-contents for different cryostratigraphic units along Arctic coasts. Knowledge of ground ice distribution will help us understand the dynamics of permafrost in regards to both climate change as well as development. The results presented here are from resistivity surveys conducted in the Western Canadian Arctic for a variety of terrestrial and coastal settings. Using an OhmMapper TR1 capacitive coupled resistivity system we measured the apparent resistivities at each of the sites using a number of survey spacings. These data were processed and inverted to create two-dimensional profiles of the survey sites. Interpretations of the survey profiles were undertaken in conjunction with data from natural exposures, Radarsat, ground penetrating radar, borehole logs, and test pits. It was found that the OhmMapper system consistently identified areas of massive ice and coarse-grained sediments with variable ice contents as well as areas with bottomfast ice and subsea permafrost. Despite extensive ground ice mapping since the 1970’s, the distribution of ice-rich permafrost is still poorly understood. This is particularly challenging problem for areas like the Mackenzie Valley and Mackenzie Delta where oil and gas development is immanent. The use of non-invasive geophysical tools help to better define ice-rich regions. The results presented in this poster help to explain apparent resistivities of permafrost with varying ice contents in several different coastal settings
Bibliography of Canadian Geomorphology