On the stability of the lithospheric geoelectrical structure resolution in Tarim – Tien Shan junction zone: application of various approaches to the magnetotelluric data inversion

№1 (2024)

Sokolova E.Yu., Dong H., Rybin A.K., Pushkarev P.Yu., Matyukov V.E.

УДК 550.372
https://doi.org/10.47148/1609-364X-2024-1-42-54

AbstractAbout the AuthorsReferences
For several decades, the intracontinental Tien Shan orogeny has served as a testing polygon for the study of modern geodynamic and seismic processes, carried out by Russian and foreign scientists at the Research Station RAS (Bishkek). The investigations have big practical significance for developing seismic hazzard zoning strategies. Magnetotelluric sounding, providing unique information on the lithosphere structures and rheology, plays an important role in the complex of applied geological and geophysical methods.
The article describes the experience of studying the deep geoelectric structure of one of the most seismically active regions of the Tien Shan, the junction zone of the orogen and the Tarim plate. This experience was obtained during the interpretation of materials from the regional profile of MT soundings that cross this zone. Comparing the results of applying three different approaches to the inversion of magnetotelluric data, which differ not only in software implementations and algorithmic foundations, but also in model dimension, allows us to assess the reliability of the allocation and revealed properties of the main structural elements in the deep conductivity section, which help to clarify the seismotectonic pattern of the studied crustal zone.
The objectives of the article also included support for new SinoProbe MT experiments.

Elena Yu. Sokolova
Leading Researcher, Department of Geoinformatics
All-Russian Research Geological Petroleum Institute
8, Varshavskoye sh., Moscow, 117105, Russia
Leading Researcher
Schmidt’s Institute of Physics of the Earth, Russian Academy of Sciences
buildi. 1, 10 Bolshaya Gruzinskaya str., Moscow, 123242, Russia
е-mail: sokol_l@mail.ru
ORCID: 0000-0002-5788-6944

Hao Dong
Associate professor
China University of Geosciences
Xueyuan Road, Beijing, Haidian District, 100083, China
е-mail: donghao@cugb.edu.cn
ORCID: 0000-0002-5457-0557

Anatoly K. Rybin
Director, Chief Researcher
Resarch Station of the Russian Academy of Sciences in Bishkek
Research Station of the Russian Academy of Sciences, Bishkek-49, 720049, Kyrgyzstan
e-mail: rybin99@yandex.ru
ORCID: 0000-0001-7810-3278

Pavel Yu. Pushkarev
Professor
Lomonosov Moscow State University, Geological Faculty
1, Leninskie gory, Moscow, 119234, Russia
e-mail: pavel_pushkarev@list.ru
ORCID: 0000-0003-2894-2609

Vitaly E. Matyukov
Senior Researcher
Research Station of the Russian Academy of Sciences in Bishkek
Research Station of the Russian Academy of Sciences, Bishkek-49, 720049, Kyrgyzstan
e-mail: vitaliy_cowboy@mail.ru
ORCID: 0000-0001-5323-786X

  1. Berdichevsky M.N., Dmitriev V.I. Models and methods of magnetotellurics. Berlin; Heidelberg: Springer; 2008. 680 p.
  2. Makarov V.I. Alekseev D.V., Leonov M.G., Batalev V.Y., Bataleva E.A., Bragin V.D., Rybin A.K., Shchelochkov G.G., Belyaev I.V., Dergunov N.T., Efimova N.N., Roslov Y.V., Munirova L.M., Pavlenkin A.D., Roecker S. Underthrusting of Tarim beneath the Tien Shan and Deep Structure of Their Junction Zone: Main Results of Seismic Experiment along MANAS Profile Kashgar-Song- Köl. Geotectonics. 2010;44(2):102–126. DOI: 10.1134/S0016852110020020.
  3. Rybin А.К., Batalev V.Y., Bataleva Е.А., Matukov V.Е. Magnetotelluric evidence of deep geodynamic settings at the junction zone of the southern Tien Shan and Tarim basin. Journal of Mining Institute. 2009;183:272–286.
  4. Rybin A.K., Bataleva E.A., Nepeina K.S., Matyukov V.E. Volumetric and spatial segmentation of the Tien Shan lithosphere according to geophysical data. Geodynamics and tectonophysics. 2021;12(3):508-543. DOI:10.5800/GT-2021-12-3-0537.
  5. Tikhonov A.N., Arsenin V.Ya. Metody resheniya nekorrektnykh zadach [Methods of solving ill-posed problems]. 2nd ed. Moscow: Nauka; 1979. 285 p.
  6. Shchelochkov G.G., Bragin V.D., Rybin A.K., Batalev V.YU., Bataleva E.A., Pavlenkin A.D., Roslov YU.V., Efimova N.N., Dergunov N.T., Belyaev I.V., Munirova L. M., Makarov V.I., Leonov M. G., Alekseev D.V., Knapp J.H., Roecker S.W. Transekt «MANAS»: pervye rezul’taty obrabotki i interpretatsii dannykh seismicheskikh Tsentral’nogo Tyan’-Shanya [Transect “MANAS”: first results of processing and interpretation of seismic data of the Central Tien Shan] In: Geodinamika vnutrikontinental’nykh orogenov i geoehkologicheskie problemy : sb. materialov chetvertogo mezhdunarodnogo simpoziuma (15-20 June 2008, Bishkek). Moscow; Bishkek; [s.n.] 2009. pp. 59–67.
  7. Cheremisina E.N., Finkel’shtein M.Ya., Deev K.V., Bol’shakov E.M. GIS INTEGRO. Status and prospects for development in the context of import substitution. Russian oil and gas geology. 2021;(3):31–40. DOI 10.31087/0016-7894-2021-3-31-40.
  8. Constable S.C., Parker R.L., Constable C.G. Occam’s inversion: A practical algorithm for generating smooth models from electromagnetic sounding data. Geophysics. 1987;52(3):289–300. DOI: 10.1190/1.1442303.
  9. Dong S.W., Li T.D., Lü Q.T., Gao R., Yang J.S., Chen X.H., Wei W.B., Zhou Q. Progress in deep lithospheric exploration of the continental China: A review of the SinoProbe. Tectonophysics. 2013;606:1–13. DOI: 10.1016/j.tecto.2013.05.038.
  10. Dong H., Egbert G.D. Divergence-free solutions to electromagnetic forward and adjoint problems: a regularization approach. Geophysical Journal International. 2019;216(2):906–918. DOI: 10.1093/gji/ggy462.
  11. Dong H., Wei W., Jin S., Ye G. Magnetotellurics in SINOPROBE Project: an Overview. 16.12.2020. 38 pp. Awailable at: http://www.mtnet.info/EMinars/20201216_Dong_EMinar.pdf (accessed 20.03.2024).
  12. Kelbert A., Meqbel N., Egbert G.D., Tandon K. ModEM: a modular system for inversion of electromagnetic geophysical data. Computers & Geosciences. 2014;66:40–53. DOI: 10.1016/j.cageo.2014.01.010.
  13. Li Zh., Roeker S., Zhihai L., Bin W., Haitao W., Schelochkov G., Bragin V. Tomographic image of the crust and upper mantle beneath the western Tien Shan from MANAS broadband deployment: possible evidence for lithospheric delamination. Tectonophysic. 2009;477(1-2):49–57. DOI: 10.1016/j.tecto.2009.05.007.
  14. Rodi W., Mackie R.L. Nonlinear conjugate gradients algorithm for 2-D magnetotelluric inversion. Geophysics. 2001;66(1):174–187.
    DOI: 10.1190/1.1444893.
  15. Sokolova E.Yu., Berdichevsky M., Varentsov I., Rybin A., Baglaenko N., Batalev V., Golubtsova N., Matukov V., Pushkarev P. Advanced methods for joint MT/MV profile studies of active orogens. The experience from the Central Tien Shan. In: Protokoll uber das 22 Kolloquium “Elektromagnetische Tiefenforschung”. Ritter O., Brasse H., eds. Potsdam; DGG; 2007. pp. 132–141.
  16. Varentsov I.M. Joint robust inversion of magnetotelluric and magnetovariational data. In: Electromagnetic Sounding of the Earth’s Interior. Spichak V., ed. Amsterdam: Elsevier; 2007. pp. 189–222. DOI: 10.1016/S0076-6895(06)40008-1.
  17. Varentsov I.M., Sokolova E.Yu., Baglaenko N.V. 2D inversion resolution in the Emtesz-Pomerania project: data simulation approach. In: Protokoll uber das 22 Kolloquium “Elektromagnetische Tiefenforschung”. Ritter O., Brasse H., eds. Potsdam; DGG; 2007. pp. 143–150. DOI: 10.13140/RG.2.1.3661.7842.

Key words: magnetotelluric soundings, 2D и 3D inversions, geoelectric structure of active orogens, South Tien Shan, Tarim plate

Section: Modeling geo objects and geo-processes