Integration of the GPR and radio-impedance techniques in studies of the Baikal rift zone

Radiowave propagation techniqueshave been very rarely applied to investigate tectonic fault zones and geoelectric profilesof the Baikal rift zone. In our study, we used a combination ofground-penetrating radar (GPR) and radioimpedance techniquesin order to identify and investigatetectonic crustal fault zones in the study area. Using soundings in the super-long, long and ultra short radio wave ranges(from tens of KHz to few GHz), we detected the tectonic fault zones in the seismically active Baikal rift zone, specifically in the Tunka depression and the areas of Southern Baikal and Kotokel lakes.Faults and fault zones were identified from impedance variations and changes in the geoelectric profiles by analyzing the radio impedance profiles and soundings in the super-long and long radio wave ranges. The georadiolocation of fault structures in the ultra-short wave range made it possible to differentiate thepatterns of tectonic disturbances up to individual seismic dislocations in sedimentary and crystalline rocks and to determine the kinematics of movements in the fault zones. The techniques used in this study complement each other and ensure obtaining adequate quantitative descriptions of the study objects. By integrating varioustechniques of radio wave diagnostics, it is possible to obtain more detailed information on the structures of the tectonic fault zones. The results obtained in this study and the radioimpedance and GPR sounding and profiling techniques developed to investigate a heterogeneous underlying medium can be used in seismological and geological engineeringsurveys of the eastern and northern regions of Russia.

1. Angarkhayeva L.Kh., 2002. Certificate of Official Registration of Computer Program No. 2002610893. Software package “Impedance” for solving problems of radio impedance sensing. ROSPATENT, Moscow, 06.06.2002 (in Russian)

2. Bashkuev Yu.B., 1996. Electrical Properties of Natural Layered Media. SB RAS Publishing House, Novosibirsk, 207 p. (in Russian)

3. Bashkuev Yu.B., Advokatov V.R., Angarkhaeva L.K., 2003. Maps of geoelectric structures of the eastern hemisphere. Izvestiya. Physics of the Solid Earth 39 (9), 778–784.

4. Bashkuev Yu.B., Khaptanov V.B., 2009. Method and Device for Measuring the Surface Impedance of the Earth's Crust in the ELF range of radio waves. Copyright Certificate No. 299005, 01.08.1989, published 27.12.2009. Inventions. Utility Models. No. 36, SU 1840791 A1 (in Russian)

5. Efremov V.N., 2013. Radioimpedance Sounding of Frozen Soils. Publishing House of Permafrost Institute SB RAS, Yakutsk, 204 p. (in Russian)

6. GeoScan32, 2013. Illustrated User Guide. LOGIS, Ramenskoye, 132 p. (in Russian)

7. Melchinov V.P., Bashkuev Yu.B., Angarkhaeva L.Kh., Buyanova D.G., 2006. Electrical Properties of Cryolithic Zone in the Eastern Regions of Russia in the Radio Range. Publishing House of BSC SB RAS, Ulan-Ude, 257 p. (in Russian)

8. Radio Engineering Device for Subsurface Sounding (Georadar) Oko-2, 2006. Technical Description. Manual. Version 2.6.2009. Logicheskie Sistemy LLC, Moscow, 101 p. (in Russian)

9. Semeikin N.P., Pomozov V.V., Dudnik A.V., 2005. Development of OKO georadars. In: A.Yu. Grinev (Ed.), Problems of subsurface radiolocation. Radiotekhnika, Moscow, p. 231–236 (in Russian)

10. Smekalin O.P., 2008. Study of Paleoseismogenic Deformations of the Southern Pribaikalie. IPE RAS, Moscow, 101 p. (in Russian)

11. Tezkan B., Saraev A., 2008. A new broadband radiomagnetotelluric instrument: applications to near surface investigations. Near Surface Geophysics 6 (4), 245–252. https://doi.org/10.3997/1873-0604.2008019.

12. Velikhov E.P. (Ed.), 2014. Interaction of Electromagnetic Fields of the Controlled Sources of the ELF range with the Ionosphere and the Earth's Crust. Materials of the All-Russia (with international participation) seminar. Vol. 1. Geological Institute KSC RAS, Apatity, 206 p. (in Russian)

13. Velikhov E.P. (Ed.), 2015. Interaction of Electromagnetic Fields of the ELF-ULF range with the Ionosphere and the Earth's Crust. Materials of the 1st All-Russia (with international participation) seminar. Vol. 2. Geological Institute KSC RAS, Apatity, 112 p. (in Russian)

14. Velikhov E.P., Zhamaletdinov A.A., Shevtsov A.N., Tokarev A.D., Kononov Y.M., Pesin L.B., Kadyshevich G.M., Pertel’ M.I., Veshchev A.V., 1998. Deep electromagnetic studies with the use of powerful ELF radio installations. Izvestiya, Physics of the Solid Earth 34 (8), 615–632.

15. Vladov M.L., Starovoitov A.V., 2004. Introduction to GPR. MSU Publishing House, Moscow, 153 p. (in Russian)

16. Zherebtsov G.A. (Ed.), 2012. Seismic Ionospheric and Seismic Electromagnetic Processes in the Baikal Rift Zone. SB RAS Publishing House, Novosibirsk, 304 p. (in Russian)