Application of the method of reflected electromagnetic waves to study cryohydrogeological conditions

The article presents a petrophysical justification for using the method of reflected electromagnetic waves (electromagnetic common depth point method (ECDP)) to differentiate geological sections by electrical properties, including the study of cryolithozones, as well as permafrost and sub-permafrost waters. An analysis of the results of the ECDP experimental work on the territory of an oil and gas field in the Republic of Sakha (Yakutia) in 2023 was carried out, including a study of the obtained distribution of the interval velocity of the electromagnetic signal with depth in a number of measurements. The result of data processing is presented in the form of a “virtual well” – a vertical distribution of specific electrical resistivity with a resolution of 2–5 m in depth. The reliability of the ECDP results is confirmed by their stable correspondence with all measured data and geological information from depths of at least 500 m, in particular, the nature of frozen rock occurrence and the position of watersaturated rocks. The advantages of the ECDP are shown, such as sensitivity of the parameter under study (the velocity of the electromagnetic signal) to changes in the physical properties of rocks, increased detail, and the non-requirement of a priori geological and geophysical information for quantitative interpretation of measurement data.

1. Alekseev S.V. (2009). Cryohydrogeological systems of the Yakutsk diamondiferous province. Novosibirsk: Geo, 319 p. (In Russ.)

2. Alpin L.M., Dayev D.S., Karinsky A.D. (1985). Theory of fields employed in geophysical prospecting. Moscow: Nedra, 407 p. (In Russ.)

3. Baker G., Jordan T., Pardy J. (2007). An introduction to ground penetrating radar (GPR). Geological Society of America Special Papers, 432, pp. 1–18. https://doi.org/10.1130/2007.2432(01)

4. Buddo I.V., Shelokhov I.A., Misyurkeeva N.V., Agafonov Y.А. (2021). Transient electromagnetic sounding in 2D, 3D, and 4D modes: sequence of geological exploration activities. Geodynamics & Tectonophysics, 12(3s), pp. 715–730. https://doi.org/10.5800/GT-2021-12-3s-0549

5. Dolgikh Y. N., Volkomirskaya L.B., Kaygorodov E.P., Sanin S.S., Kuznetsov V.I., Gulevich O.A., Reznikov A.E., Varenkov V.V. (2021). The reflected electromagnetic wave CDP method (ECDP) testing results and possibilities for the future oil and gas exploration. Proceedings of the conference “Tyumen 2021”, March 2021, pp. 1–6. https://doi.org/10.3997/2214-4609.202150007

6. Dortman, N.B. (1984). Physical properties of rocks and minerals (petrophysics). Moscow: Nedra, 455 p. (In Russ.)

7. Doyoro, Y.G., Chang, PY., Puntu, J.M., Lin DJ., Huu T.V., Rahmalia D.A., Shie MS. (2022). A review of open software resources in python for electrical resistivity modelling. Geoscience Letters, 9, 3. https://doi.org/10.1186/s40562-022-00214-1

8. Electrical Prospecting: A Manual on Electrical Prospecting Practice for Students of Geophysical Specialties (2005). Edited by Prof. V.K. Khmelevsky, I.N. Modin, A.G. Yakovlev. Moscow, 311 p. (In Russ.)

9. Farzaneh M., Fofana I., Hemmatjou H. (2004). Electrical properties of snow. Annual Report - Conference on Electrical Insulation and Dielectric Phenomena, CEIDP, pp. 611–614.

10. Frolov A.D. (2005). Electric and elastic properties of frozen earth materials. Second revised edition. Pushchino: ONTI PSC RAS, 607 p. (In Russ.)

11. Glen, J. W., Paren, J. G. (1975). The Electrical Properties of Snow and Ice. Journal of Glaciology, 15(73), pp. 15–38, https://doi.org/10.3189/S0022143000034249

12. Hou D., Wang X., Zou J. (2020). Inversion of soil resistivity by using CSAMT method. IEEE International Conference on High Voltage Engineering and Application (ICHVE), Beijing, China, pp. 1–4. https://doi.org/10.1109/ICHVE49031.2020.9279948

13. Khmelevskoy V.K., Shevnin V.A., Modin I.N., Yakovlev A.G. (1992). Electrical sounding of the geological environment. Part 2. Interpretation and practical application. Moscow: Moscow State University, 200 p. (In Russ.)

14. Khmelevskoy V.K. (1999). Geophysical Methods of the Earth’s Crust Studies. Book 2. Regional, exploration, engineering and ecological geophysics. Dubna: International University of Nature, Society and Man “Dubna”, 184 p. (In Russ.)

15. Kilpio E.Yu., Shcherbakov I.A. (2022). On the results in physics obtained in 2020-2021. Doklady Physics, 506, 2, pp. 3–33. https://doi.org/10.31857/S2686740022070069

16. Melnikanovitskii I.M., Ryapolova V.A., Khordikainen M.A. (1982) Methods of geophysical research in prospecting and exploration of fresh water deposits. Moscow: Nedra, 239 p. (In Russ.).

17. Olayinka A., Yaramanci U. (2010). Assessment of the reliability of 2D inversion of apparent resistivity data. Geophysical Prospecting, 48, pp. 293–316. https://doi.org/10.1046/j.1365-2478.2000.00173.x

18. Otsimik A.A., Buddo I.V. (2023). Cryohydrogeological settings appraisal by shallow near-field TEM sounding: a case study of the western part of the Yakut artesian basin. Earth sciences and subsoil use, 46(2), pp. 160–181. (In Russ.) https://doi.org/10.21285/2686-9993-2023-46-2-160-181

19. Wu Z., Liu Sh. (2013). Imaging the debris internal structure and estimating the effect of debris layer on ablation of Glacier ice. Journal of the Geological Society of India, 80. https://doi.org/10.1007/s12594-012-0211-z

20. Zakharenko V.N., Krakovetskiy Yu.K., Parnachev V.P., Popov L.N. (2012). On the electrical conductivity of permafrost rocks. Vestnik Tomskogo gosudarstvennogo universiteta, 359, pp. 182–187, (In Russ.)

21. Zykov Yu.D. (2007). Geophysical Methods for Permafrost Studies. Moscow: Publishing House of Moscow University, 272 p. (In Russ.)