Active fiber-optic distributed temperature sensing to assess the geothermal potential and groundwater flow over the traditional territory of the Lù'àn Män Ku Dän, Yukon

• Main Authors: Raymond, Jasmin, Chapman, Fiona, Klepikova, Maria, Bour, Olivier, Soucy Laroche, Renaud
• Other Authors: Centre Eau Terre Environnement Québec (INRS - ETE), Institut National de la Recherche Scientifique Québec (INRS), Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), European Geosciences Union
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2024
• Subjects: [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology; First Nations; glacier*; Yukon
• Online Access: https://hal.science/hal-04509203; https://doi.org/10.5194/egusphere-egu24-20169

International audience The traditional territory of the Lù'àn Män Ku Dän (Kluane Lake People) is found along the Saint Elias Mountains in Yukon. It hosts the Burwash Landing community, home of the Kluane First Nation, which is one of eleven self-governing First Nations operating in tripartite with Yukon Government and Canada. Burwash Landing is primarily dependent on diesel for space heating and power generation. Cutting-edge technologies were deployed in the scope of geothermal resource assessment to evaluate the thermal state and properties of the subsurface. Active distributed temperature sensing was conducted with a composite heating and fiber-optic cable installed in the water column of two existing wells with the objective of quantifying the geothermal potential and groundwater flow along available wellbores. Heat injection tests were made in the 220 and 385 m deep wells located on the south and north side of the Denali fault, near a probable releasing bend that is favorable to permeability. Melting glacier water infiltrates in mountains and groundwater flows toward Kluane Lake, which is hypothesized to be a major groundwater discharge zone. The shallower well is at an altitude of 925 masl and intercepted 40 m of quaternary deposits before hitting fractured bedrock while the deeper well is at the valley bottom near the lake (altitude of 795 masl) and entirely drilled in quaternary deposits. Passive temperature monitoring was initially made and revealed a geothermal gradient of 34 ⁰C km-1 and 47 ⁰C km-1 in the shallow south side and deep north side wells. Heat was injected during active tests for 2 and 3 days and thermal recovery was monitored for 6 and 8 days, respectively. Temperature was measured every 25 cm at 4-minute intervals. The infinite line source equation and the superposition principle were used to analyze data and calculate a thermal conductivity profile. Nearly continuous ground thermal properties and temperature profiles were combined to assess the Earth natural heat flux, considering ...