Coupling GPR and ERT data interpretation to study the thermal imprint of a river in Syrdakh (Central Yakutia, Russia)

• Published in: 18th International Conference on Ground Penetrating Radar, Golden, Colorado, 14–19 June 2020
• Main Authors: Saintenoy, Albane, Pessel, Marc, Grenier, Christophe, Léger, Emmanuel, Danilov, Kencheeri, Bazhin, Kirill, Khristoforov, Ivan, Séjourné, Antoine, Konstantinov, Pasha
• Other Authors: Géosciences Paris Saclay (GEOPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Melnikov Permafrost Institut, Russian Academy of Sciences Moscow (RAS)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2020
• Subjects: [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]; permafrost; Yakutia; Siberia
• Online Access: https://hal.science/hal-04455273; https://hal.science/hal-04455273/document; https://hal.science/hal-04455273/file/Ext-Abs-Syrdakh-fin.pdf; https://doi.org/10.1190/gpr2020-025.1

International audience The thermal influence of a river on the surface conditions of a continuous permafrost in Yedoma sediments of Central Yakutia (Siberia, Russia) is studied by active layer (AL) thickness measurements along a cross section, CS9, with direct AL measurements (e.g. drilling), Ground-Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT) during late September 2017 and 2018. Reflections on the unfrozen/frozen interface when shallower than 2 m is detected on GPR data while ERT data inversion provides models of electrical resistivity down to 5 m. We study the effect of constraining ERT data inversion (using BERT software) with interface depth derived from GPR data and direct AL measurements, where available. The geophysical data enable us to reveal spatial variability in active layer depths, possibly related to river thermal influence. We compare our results with the 0 • C isotherm obtained through simulating heat transfers with prescribed soil water content properties. We deduce a first estimate of the thermal imprint of the river.