| Summary: | Degree: Master of Science Abstract: The Alaska Highway through Southwestern Yukon is located in the discontinuous permafrost zone with many areas of the highway corridor associated with degrading permafrost. Given the strategic value of the corridor, it is critical to have a clear understanding of permafrost characteristics and distribution, particularly in the context of a changing climate. In the Beaver Creek area, the Alaska Highway traverses both glaciated and non‐glaciated terrain dating from the last glacial maximum. Permafrost characteristics are strongly influenced by regional glacial history, including the distribution of relict Pleistocene syngenetic permafrost. This thesis characterizes permafrost along the Alaska Highway between Beaver Creek and the Alaska border using a multidisciplinary approach. Our surveys include electrical resistivity tomography (ERT), airborne electromagnetics (AEM), geomorphological mapping, permafrost drilling, cryostratigraphic interpretations, geochemical analyses, and environmental monitoring to define the distribution and extent of permafrost within the study area. Using a combination of AEM and ERT data, we are able to define boundaries between non‐glaciated terrain and glaciated terrain, highlight regional bedrock geology, outline valley fill geometry, image the thermal impact of small and large scale surface water features, and estimate the depth of permafrost. Radiocarbon dating and stable isotope analyses of δ18O and δ2H combined with detailed cryostratigraphy highlight the ice‐rich nature of shallow Holocene permafrost and confirmed the presence of relict late Pleistocene ground ice at depth. The outcomes from this study will assist in the development of future mitigation strategies and maintenance plans for the highway.
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