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Proquest Dissertations NOTE TO USERS This reproduction is the best copy available. UMI' nm u Ottawa L'Universit6 canadienne Canada's university ITTTT FACULTE DES ETUDES SUPERIEURES l^s FACULTY OF GRADUATE AND ET POSTDOCTORALES u Ottawa POSTDOCTORAL STUDIES i.'UniveisiU; emwidk'nne Canada's university Melanie St-Jean AUTEUR DE LA THESE / AUTHOR OF THESIS M.Sc. (Geography) GRADE'/DEGREE Department of Geography TACULTOOTLTDEP^RTEIW^ Nature and Origin of Massive Ground Ice Bodies, Yukon Territory and Alaska TITRE DE LA THESE / TITLE OF THESIS B. Lauriol DIRECTEUR (DIRECTRICE) DE LA THESE / THESIS SUPERVISOR I. Clark CO-DIRECTEUR (CO-DIRECTRICE) DE LA THESE / THESIS CO-SUPERVISOR EXAMINATEURS (EXAMINATRICES) DE LA THESE/THESIS EXAMINERS A. Lewkowicz C Zdanowicz Gary W. Slater Le Doyen de la Faculte des etudes superieures et postdoctorales / Dean of the Faculty of Graduate and Postdoctoral Studies NATURE AND ORIGIN OF MASSIVE GROUND ICE BODIES, YUKON TERRITORY AND ALASKA A thesis submitted to The school of Graduate Studies and Research In partial fulfillment of the requirements For the degree Master of Science Melanie St-Jean Department of Geography University of Ottawa Ottawa, Canada May 2009 Library and Archives Bibliotheque et 1*1 Canada Archives Canada Published Heritage Direction du Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington Ottawa ON K1A 0N4 Ottawa ON K1A 0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-59454-4 Our file Notre reference ISBN: 978-0-494-59454-4 NOTICE: AVIS: The author has granted a non­ L'auteur a accorde une licence non exclusive exclusive license allowing Library and permettant a la Bibliotheque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par I'lnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans le loan, distribute and sell theses monde, a des fins commerciales ou autres, sur worldwide, for commercial or non­ support microforme, papier, electronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in this et des droits moraux qui protege cette these. Ni thesis. Neither the thesis nor la these ni des extra its substantiels de celle-ci substantial extracts from it may be ne doivent etre imprimes ou autrement printed or otherwise reproduced reproduits sans son autorisation. without the author's permission. In compliance with the Canadian Conformement a la loi canadienne sur la Privacy Act some supporting forms protection de la vie privee, quelques may have been removed from this formulaires secondaires ont ete enleves de thesis. cette these. While these forms may be included Bien que ces formulaires aient inclus dans in the document page count, their la pagination, il n'y aura aucun contenu removal does not represent any loss manquant. of content from the thesis. 1*1 Canada © Melanie St-Jean, Ottawa, Canada, 2009 Table of Contents List of figures and tables v Abstract vii Intellectual Contribution viii Acknowledgements viii Chapter 1: Introduction 1 Chapter 2: Literature Review 4 Permafrost and Ground Ice. 4 Buried Ice 5 Intrasedimental Ice 5 Ice Wedge Ice 7 Identification Methods and Approaches 11 Petrographic Analysis 13 Stable O-H Isotopes 15 Molar Gas Ratios 18 Gases entrapped in glacier 19 Gases entrapped in intrasedimental ice 20 Chapter 3: Methods and Techniques 22 i Field Investigation 22 Laboratory Methods and Techniques 24 Petrographic Analysis 24 Stable O-H Isotopes 25 Soil and Organic Samples 27 Gas Composition 28 Chapter 4: Manuscript 1 30 An improved method for measurement of isotopic and gas ratios (02/Ar, N2/Ar, 5180, 8 N and 6 Ar) of air entrapped in permafrost ice Abstract 31 Introduction 32 11 Methodology 33 Cutting and Storage 33 Extraction 33 Mass Spectrometry Analysis 35 Verification of Method 35 Discussion 38 Modification to the Extraction Technique 38 Reproducibility of Ice Measurements (Variability) 39 Summary and Conclusions 41 References 43 Chapter 5: Manuscript 2 47 Investigation on the Source of Infill of Ice Wedges Using Crystallography, Stable O-H Isotopes of Ice, and Elemental - Isotopic composition of occluded 02, N2 and Ar gases Abstract 48 Introduction 49 Site Description 50 Old Crow region, northern Yukon Territory 52 Moose Lake, central Yukon Territory 53 Vault Creek tunnel, central Alaska 54 Sampling and Analytical Methods 56 Ice Crystallography 56 Stable O-H Isotope Composition 56 Gas Composition 57 Results 58 Old Crow region, northern Yukon Territory 58 Moose Lake, central Yukon Territory 61 Vault Creek tunnel, central Alaska 62 Discussion 63 Ice Crystallography 63 Stable O-H Isotope Composition 63 Gas Composition 66 Infilling Process in Ice Wedges 67 Conclusion 68 Acknowledgments 69 iii References 70 Chapter 6: Conclusion 74 References 77 Appendix 1: Extraction technique step-by-step procedures 85 Appendix 2: Gas Ratios Results 89 Appendix 3: Crystallographic Analyses 90 IV List of figures and tables Chapter 1-3 Figure 1 A general classification of massive ground ice types 4 Figure 2 Genetic classification of ground ice 6 Figure 3 Global Meteoric Water Line 16 Figure 4 Rainout effect on 82H and 5180 values 17 Figure 5 Study area for summer 2006 22 Figure 6 Map of Yukon and Alaska showing location of the 23 three ice wedge sites mentioned in the thesis Table 1 Thin section analysis details 25 Chapter 4: Manuscript 1 Figure 1 Wet extraction line 34 Figure 2 Comparison of the gas ratios (02/Ar and N2/Ar) of the 36 working standard with the atmospheric values Figure 3 Co-isotopes diagram (S180/ 840Ar) of the working 38 standard, compared with the atmospheric values Figure 4 Co-isotopes diagram (8180/815N) of the working 38 standard, compared with the atmospheric values Table 1 Air standard measurements 37 Table 2 Standard deviation for each ice block 40 Chapter 5: Manuscript 2 Figure 1 Map of Yukon and Alaska showing location of the 51 three ice wedge sites mentioned in this study. Figure 2 Photographs from ice wedges sampled along the 52 Eagle, Bell and Porcupine Rivers. Photos were taken in July 2006. v Figure 3 Schematic diagrams of Moose Lake ice wedge site in 53 2007-2008. A) Large scale view of the area. B) Cross- section front view of the ice wedges. C) Cross-section side view of the ice wedges Figure 4 Photograph of the fhermokart landscape found at the 54 Moose Lake site. Photo taken in July 2008 Figure 5 Photographs from the Vault Creek tunnel, Fairbanks, 55 showing: A) Structure of the wedge ice; and B) Example of a sampled ice wedge. Photos taken in July 2007. Figure 6 A) Vertical thin section under plain light showing ice 58 bubbles; B) Horizontal thin section under crossed polarizing filters; and C) Vertical thin section under crossed polaroids, of wedge ice from the Old Crow area, northern Yukon. Figure 7 Stable O-H isotope composition of the ice wedges in 59 the Old Crow area and Moose Lake region. Figure 8 A) Molar gas ratios (N2/Ar and OzlAr) in the wedge 60 ice samples collected from the Old Crow region in northern Yukon, near Moose Lake in central Yukon, and in the Vault Creek tunnel, central Alaska. B) 818Oo2 and 02/Ar composition of gases entrapped in the wedge ice samples collected from the Old Crow region in northern Yukon, near Moose Lake in central Yukon, and in the Vault Creek tunnel, central Alaska Figure 9 A) Vertical thin section under crossed polarizing 61 filters; B) Horizontal thin section under crossed polaroids; and C) Vertical thin section under plain light showing ice bubbles of wedge ice from the Moose Lake area. Figure 10 A) Vertical thin section under plain light showing ice 62 bubbles; and B) Vertical thin section under crossed polarizing filters of wedge ice from the Vault Creek tunnel, central Alaska. Figure 11 Deuterium excess and deuterium in the wedge ice 65 samples collected from the Old Crow region in northern Yukon, near Moose Lake in central Yukon vi ABSTRACT Gas bubbles in ice hold relevant information on the origin and process of formation, distinguishing between an atmospheric and dissolved origin. Using ice crystallography, stable O-H isotopes and gas composition, this thesis provides new clues to the understanding of ice wedge formation and filling process in the Yukon Territory and Alaska. An improved extraction line and mass spectrometry technique were used to analyze the gas composition of ice bubbles (O2, N2 and Ar). Conclusions from this study infer that climatic conditions may influence the source of infilling during ice wedge growth. Wet and dry environments have result in two different signatures in ice wedges. The Vault Creek tunnel ice wedges in Alaska, dated to the late Pleistocene, a cold and dry period, preserve stable O-H isotope and gas compositions similar to those expected for ice formed by snow densification. On the other hand, ice wedges from the Old Crow region, dated to the late Holocene, preserved isotopic and gas compositions more similar to those expected for ice formed by the freezing of liquid water. In some cases, the results from the occluded gases (O2, N2 and Ar) showed low oxygen concentration and high 5180 values, indicating respiration prior to formation. These results are significant to palaeoclimatic interpretation of ice wedges in permafrost areas. Vll ATTESTATION INTELLECTUAL CONTRIBUTION The main focus of the thesis is on the analysis of the gas composition within massive ground ice bodies using the wet extraction technique. In terms of laboratory work, I personally devoted most of my time to improvement of the wet extraction line and on the analysis of the gas composition (O2, N2 and Ar) of air trapped in the ice coming from the all the sites presented in the thesis.
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