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TitleMolar gas ratios of air entrapped in ice: A new tool to determine the origin of relict massive ground ice bodies in permafrost
AuthorCardyn, R; Clark, I D; Lacelle, D; Lauriol, B; Zdanowicz, C; Calmels, F
SourceQuaternary Research (New York) vol. 68, 2007 p. 239-248, (Open Access)
Alt SeriesEarth Sciences Sector, Contribution Series 20080605
PublisherCambridge University Press (CUP)
Mediapaper; on-line; digital
File formatpdf
Subjectssurficial geology/geomorphology; permafrost; ground ice; freezing ground; gas; ice samples; ice; glaciers; traps; isotope ratios; isotopes; isotopic studies
Illustrationsphotographs; plots; location maps
Released2017 01 20
AbstractThe molar ratios of atmospheric gases change during dissolution in water due to differences in their relative solubilities.We exploited this characteristic to develop a tool to clarify the origin of ice formations in permafrost regions. Extracted from ice, molar gas ratios can distinguish buried glacier ice from intrasedimental ground ice formed by freezing groundwaters. An extraction line was built to isolate gases from ice by melting and trapping with liquidHe, followed by analysis of N2, O2,, Ar, 18OO2 and 15NN2, by continuous flow mass spectrometry. The method was tested using glacier ice, aufeis ice (river icing) and intrasedimental ground ice from sites in the Canadian Arctic. O2/Ar and N2/Ar ratios clearly distinguish between atmospheric gas in glacial ice and gases from intrasedimental ground ice, which are exsolved from freezing water. delta15NN2 and delta18OO2 in glacier ice, aufeis ice and intrasedimental ground ice do not show clear distinguishing trends as they are affected by various physical processes during formation such as gravitational settling, excess
air addition, mixing with snow pack, and respiration.