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Christina Miceli MSc Candidate Supervisor: Antoni Lewkowicz University of Ottawa

Use of Direct Current (DC) Resistivity Profiling To Investigate Thin Permafrost in the Alaska Highway Corridor. Christina Miceli MSc Candidate Supervisor: Antoni Lewkowicz University of Ottawa. Permafrost. Ground that remains below 0°C for a minimum of 2 years Discontinuous

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Christina Miceli MSc Candidate Supervisor: Antoni Lewkowicz University of Ottawa

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  1. Use of Direct Current (DC) Resistivity Profiling To Investigate Thin Permafrost in the Alaska Highway Corridor Christina Miceli MSc Candidate Supervisor: Antoni Lewkowicz University of Ottawa

  2. Permafrost • Ground that remains below 0°C for a minimum of 2 years Discontinuous • Thin and occupies only parts of the landscape • Susceptible to thaw • Permafrost has disappeared at half the sites where it was found in a 1964 survey (NRCAN, 1975) Widespread Discontinuous Continuous Sporadic Discontinuous

  3. Research Sites • Ten research sites along 1200 km of the Alaska Highway • Whitehorse, Yukon to near Fort St. John, B.C.

  4. Methods • Set up ground temperature, air temperature, snow monitoring at each site 20 m 20 m 20 m 20 m

  5. Methods • Direct Current (DC) Resistivity Profiling • - Electrical current (from a car battery) passed into the ground through a line of electrodes to map out an area’s resistivity • -Resistivity differs greatly between frozen and thawed soil because water is a good conductor of electrical energy and ice is a poor conductor

  6. Results • Resistivity profiles show thin permafrost at almost all of the sites. Permafrost Unfrozen Threshold is at around 300 ohm-metres 4-10 m thick permafrost

  7. Little evidence of permafrost at the surface of some sites even though the resistivity profiles show it is present Permafrost Unfrozen Threshold is at around 300 ohm-metres 4 m thick permafrost

  8. Research Significance • Unique experiment for thin permafrost • Little knowledge of freeze-thaw cycles • Allows for • Short term/Seasonal monitoring • Long term/Climate monitoring • Help to predict and better understand • Problems with infrastructure over thin permafrost • Geohazards • Hydrological and ecological change

  9. Future Work • Additional Surveys in Winter, Summer, and Fall 2011 • Results will tell us about the dynamics of thin permafrost in relation to climate and climate change

  10. Acknowledgments • Royal Canadian Geographical Society • Royal Bank of Canada’s Blue Water Project • NSERC, University of Ottawa, Natural Resources Canada • Max Duguay

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