DESIGN OF FIELD EXPERIMENTS FOR SUBSTANTIATION OF PERMAFROST MONITORING TECHNOLOGY
V.N. Glinskikh, A.A. Fedoseev, M.N. Nikitenko, I.V. Mikhaylov, D.A. Bukhtiyarov
Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: frozen rocks, electromagnetic monitoring, cross-borehole exploration, geoelectric model, transient electromagnetic sounding, design of field experiments
Abstract
The work is aimed at the theoretical development and modeling of field experiments for a high-resolution geophysical technique of transient electromagnetic sounding in order to substantiate a permafrost monitoring technology. To select the optimal parameters of the sounding system, we established the dynamics of changes in the registered electromotive force in terms of the distance between the signal transmitter and receiver. Based on field temperature measurements at the geophysical test site and the elucidated interrelation between the electrical resistivity and temperature values, we calculated the variations in the resistivity of the near-surface loams and clay loams for the period late January - early April 2022. The dynamics of changes in the boundary between seasonally frozen and underlying rocks was traced. Using the resistivity values calculated from the measured temperatures, we carried out numerical modeling of the electromotive force amplitude to identify the dependence of the signals on the shift of the boundary due to freezing. In addition, approaches were proposed to verification of the results obtained.
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