Vestnik КRAUNC. Fiz.-Mat. nauki. 2024. vol. 49. no. 4. P. 171-184. ISSN 2079-6641

PHYSICS
https://doi.org/10.26117/2079-6641-2024-49-4-171-184
Research Article
Full text in Russian
MSC 86-10

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Modeling of the Directions of Rock Principle Stress Axes During Earthquake Preparation

M. I. Gapeev^{\ast}, A. A. Solodchuk

Institute of Cosmophysical Research and Radio Wave Propagation FEB RAS, 684034, Paratunka, Mirnaya Str., 7, Russia

Abstract. The process of rock stress-strain state change causes acoustic radiation, which is called rock acoustic emission or geoacoustic emission. The relation between the earthquake preparation process and rock acoustic emission variations, which are called pre-seismic anomalies, has been stated in a number of investigations. The general mechanism of occurrences of these anomalies is associated with the fact that formation of a preparing earthquake source causes changes in the stress-strain state of rocks, surrounding it. One of the kinds of anomalies, occurring at the final stage of earthquake preparation, is the appearance of clearly expressed direction of acoustic activity. The main hypothesis of occurrence of this phenomenon is that a preparing earthquake source impact causes formation of constant direction of principle stress axes at an observation point. In their turn, the direction of these axes determines the primary orientation of acoustic radiation sources. To confirm this hypothesis, axis orientations of the main stresses, determined by the earthquake preparation process, were modeled. The estimates are based on the model constructed within the framework of elasticity linear theory where the Earth crust is considered in the form a homogeneous isotropic elastic half-space and the force impact at a preparing earthquake source is considered in the form of a combination of forces double pairs. Elastic deformation potential energy, accumulated during the earthquake preparation process, is taken into account. In the paper, we used the data from the catalog of earthquake source mechanics «The Global Centroid-Moment-Tensor Catalog» on seismic events occurred near Kamchatka peninsula from 1976 until 2020. As long as the acoustic radiation direction depends on the azimuthal direction to earthquake epicenter, all the considered seismic events were divided into three groups by the method of K-averages according to spatial locations of their epicenters. The modeling results were compared with experimental estimates of the main stress axis directions at Mikizha observation site (52.99° N, 158.22° E). The estimates were earlier obtained based on the geoacoustic emission directivity anomalies. It was shown that histograms of main stress axis direction distributions agree with the results of estimates for two groups of earthquakes. Modal intervals of distribution histograms fall within the range of experimental estimates from 290° to 320° and from 20° to 50° accordingly.

Key words: geoacoustic emission, pre-seismic anomalies, mathematical modeling, main stress axes.

Received: 18.10.2024; Revised: 11.11.2024; Accepted: 25.11.2024; First online: 28.11.2024

For citation. Gapeev M. I., Solodchuk A. A. Modeling of the directions of rock principle stress axes during earthquake preparation. Vestnik KRAUNC. Fiz.-mat. nauki. 2024, 49: 4, 171-184. EDN: RHEQMO. https://doi.org/10.26117/2079-6641-2024-49-4-171-184.

Funding. The work was supported by IKIR FEB RAS State Task (subject registration No. 124012300245-2)

Competing interests. The authors declare that there are no conflicts of interest regarding authorship and publication.

Contribution and Responsibility. All authors contributed to this article. Authors are solely responsible for providing the final version of the article in print. The final version of the manuscript was approved by all authors.

^{\ast}Correspondence: E-mail: gapeev.sci@yandex.ru

The content is published under the terms of the Creative Commons Attribution 4.0 International License

© Gapeev M. I., Solodchuk A. A., 2024

© Institute of Cosmophysical Research and Radio Wave Propagation, 2024 (original layout, design, compilation)

References

1. Marapulets Y., Solodchuk A., Lukovenkova O., Mishchenko M., Shcherbina A. Sound Range AE as a Tool for Diagnostics of Large Technical and Natural Objects, Sensors, 2023, vol. 23, no. 3:1269, pp. 1–14. DOI: 10.3390/s23031269.
2. Lavrov A. V., Shkuratnik V. L. Deformation- and fracture-induced acoustic emission in rocks (review), Acoustical Physics, 2005, vol. 51, pp. 6-18 (In Russian).
3. Gik L. D. Nonlinearity of granular and cracked rocks in the conditions of small strains, Physical Mesomechanics, vol. 8, no. 1, pp. 81–89 (In Russian).
4. Morgunov V. A., Lyubashevsky M. N., Fabricius V. Z., Fabricius Z. E. Geoacoustic harbinger of the Spitak earthquake [Geoakusticheskiy predvestnik Spitakskogo zemletryaseniya], Journal of Volcanology and Seismology, 1991. No. 4, pp. 104-106 (In Russian).
5. Gregori G.P., Poscolieri M., Paparo G., De Simone S., Rafanelli C., Ventrice G. “Storms of crustal stress” and AE earthquake precursors, Natural Hazards and Earth System Sciences, 2010. vol. 10, no. 2, pp. 319–337. DOI: 10.5194/nhess-10-319-2010.
6. Marapulets Y. V., Shevtsovs B. M., Larionov I. A., Mishchenko M. A., Shcherbina A. O, Solodchuk A. A. Geoacoustic emission response to deformation processes activation during earthquake preparation, Russ. J. of Pac. Geol, 2012, no. 6, 457–464. DOI: 10.1134/S1819714012060048.
7. Marapulets Y. V., Shcherbina A. O. Assessing the orientation of the axis of maximum compression of rocks with a combined point receiver system, Acoustical Physics, vol. 64, no. 6, pp. 742–749.
8. Vinogradov S. D. Conditions at the rupture and spectra of the waves emitted by it, Izvestiya [Usloviya na razryve i spektry izluchaemykh im voln], Physics of the Solid Earth, 1976, vol. 7, pp. 20–26.
9. Shamina O. G. Poniatovskaya V. I. Model studies of inhomogeneous and fractured media [Model’nye issledovaniya neodnorodnykh i treshchinovatykh sred], Moscow, IFZ RAS, 1993, 179 p. (In Russian).
10. Marapulets Yu. V. High-frequency acousto-emission effect during deformation of near-surface sedimentary rocks in a seismically active region [Vysokochastotnyy akustoemissionnyy effekt pri deformirovanii pripoverkhnostnykh osadochnykh porod v seysmoaktivnom regione], Diss. . . . Doc. Sci. (Phys.-Math.). Institute of Marine Geology and Geophysics FEB RAS, Institute of Volcanology and Seismology FEB RAS, Institute of Cosmophysical Research and RadioWave Propogation FEB RAS, 2015, 210 p. (In Russian).
11. Aki K., Richards P. Quantitative Seismology, 2nd ed., Cambridge, University Science Books, 2002, 704 p.
12. Lurie A. I. Theory of elasticity [Teoriya uprugosti], Moscow, Nauka, 1970, 940 p. (In Russian).
13. Segall P. Earthquake and volcano deformation, Princeton, Princeton University Press, 2010, 456 p.
14. The Global Centroid-Moment-Tensor Catalog https://www.globalcmt.org/.
15. Dobrovol’skiy I.P. Mathematical theory of prediction and preparation of a tectonic earthquake [Matematicheskaya teoriya podgotovki i prognoza tektonicheskogo zemletryaseniya], Moscow, FIZMATLIT, 2009, 240 p. (In Russian).
16. Gapeev M., Marapulets Y. Modeling Locations with Enhanced Earth’s Crust Deformation during Earthquake Preparation near the Kamchatka Peninsula, Applied Sciences, 2022, vol. 13, no. 1:290, pp. 1–14. DOI: 10.3390/app13010290.

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