Center for Geodynamic Safety, Polar Division, Norilsk Nickel, Norilsk, Russia:

V. P. Marysyuk, Director, Candidate of Engineering Sciences, marysyukvp@tf.nk.nornik.ru
O. V. Sitnikova, Leading Engineer

Saint-Petersburg Mining University, Saint-Petersburg, Russia:
S. V. Tsirel, Senior Researcher, Doctor of Engineering Sciences

VNIMI, Saint-Petersburg, Russia:
S. N. Mulev, Head of Laboratory

The article uses the case study of Skalistaya mine to consider the role of tectonic structure and mining sequence in geodynamic activity of rock mass. It is emphasized that mining affects both the faults that define the structure of a deposit and the currently most active faults. Specifically, the scope of the article covers the influence of flexural fold — knee-folded strata or interfaces that take an intermediate position between the plicative and disjunctive faults. On the whole, with regard to the general level of seismic activity, flexural folds stand down the faults and even plicative dislocations, but removal of large volumes of rocks and placement of low-strength backfill material in mined-out voids activates flexural folds. Under mining-induced alteration of stress state, the knee branch of a flexural fold (central segment of the step) “tends” either to becoming a slide line (and the flexure fold itself — to a fault) or, vice versa, to strenghtening. In Skalistaya mine, early stage mining operations left the flexural fold aside. However, later on, the flexure fold appeared at the intersection of two zones of abatement presssure, which resulted in an increase in the seismic activity, especially when mining directly covered the area of the knee-fold of the deposit. It is hypothesized that mining in the zone of the flexureal fold will induce geodynamic activation (weakening with the distance from the “double“ zone of abatement pressure), and upon mining completion, geodynamic activity will abate (at a certain growth of geodynamic hazards at closing portions of the flexural fold).

1. Aplonov S. V. Geodinamika (Geodynamics). Saint Petersburg : Publishing House of Saint Petersburg State University, 2001. 360 p.
2. Geodinamicheskoe rayonirovanie nedr : metodicheskie ukazaniya (Geodynamic zoning of soils : methodic regulations). Under the editorship by I. M. Petukhov, I. M. Batugina. Leningrad : Publishing House of Research Institute of Mining Geomechanics and Mine Surveying (VNIMI), Kuzbass Polutechnic Institute, 1990. 129 p.
3. Shabarov A. N., Dupak Yu. N., Tsirel S. V. et al. Prakticheskie prilozheniya geodinamiki nedr (Practical applications of soil geodynamics). Gornaya geomekhanika i marksheyderiya v III tysyacheletii (Mining geomechanics and mine surveying in the III millennium). Saint Petersburg : Research Institute of Mining Geomechanics and Mine Surveying (VNIMI), 2004. pp. 137–161.
4. Yakovlev D. V., Lazarevich T.I., Tsirel S. V. Genezis i razvitie prirodno-tekhnogennoy seysmoaktivnosti Kuzbassa (Genesis and development of natural-technogenic seismic activity of Kuzbass). Ugol = Russian coal. 2013. No. 10. pp. 53–59.
5. Shabarov A. N., Dupak Yu. N., Vatutin A. S. Tektonicheski napryazhennye i razgruzhennye zony v gornom massive (Tectonically stressed and unloaded zones in rock massif). Ugol = Russian coal. 1994. No. 7. pp. 28–30.
6. Arshavsky V. V., Badtiev B. P., Tsirel S. V., Shabarov A. N. Analysis and methods of controlling the geodynamics situation in the mines of MMC Norilsk Nickel Group. Proceedings of 2^nd Saint Petersburg International Conference and Exhibition. Houten, 2006. Vol. 1. pp. 576–581.
7. Geologicheskiy slovar. Tom 3 (Geological dictionary. Volume 3). Saint Petersburg : A. P. Karpinsky Russian Geological Research Institute (VSEGEI). 300 p. (in Russian)
8. Sviridenko L. P. Fleksura Polkanova i ee rol v geodinamike Vostochno-Evropeyskoy platformy (Polkanov's flexure and its part in East-European platform geodynamics). Svyaz poverkhnostnykh struktur zemnoy kory s glubinnymi : materialy XIV Mezhdunarodnoy konferentsii (Connection of surface structures of the Earth's crust with deep ores: materials of the XIV international Conference). Petrozavodsk : Karelian Research Centre of Russian Academy of Sciences, 2008. Part 2. pp. 171–173.
9. Ezhova I. T., Efremenko M. A., Tregub A. I. Seysmicheskaya aktivnost i neotektonika Voronezhskogo kristallicheskogo massiva (Seismic activity and neotectonics of Voronezh crystalline massif). Vestnik Voronezhskogo Gosudarstvennogo Universiteta. Seriya: Geologiya = Proceedings of Voronezh State University. Geology. 2010. No. 1. pp. 229–231.
10. Garber I. S., Grigorev V. E., Dupak Yu. N. et al. Razryvnye narusheniya ugolnykh plastov (po materialam shakhtnoy geologii) (Disjunctive dislocations of coal layers (according to the materials of mine geology)). Leningrad : Nedra, 1979. 190 p.
11. You Z. M., Chen J. P. Inversion analysis of initial geostress in tunnel of DaPing mountain. Disaster Advances. 2013. Vol. 6, Iss. 3. pp. 56–61.
12. Suorineni F. T., Hebblewhite B., Saydam S. Geomechanics challenges of contemporary deep mining: a suggested model for increasing future mining safety and productivity. Journal of the Southern African Institute of Mining and Metallurgy. 2014. Vol. 114, Nо. 12. pp. 1023–1032.
13. Fischer K., Henk A. A workfl ow for building and calibrating 3-D geomechanical models. A case study for a gas reservoir in the North German Basin. Solid Earth. 2013. Vol. 4.2. pp. 347–355.
14. Karelin V. N., Marysyuk V. P., Nagovitsin Yu. N., Vilchinskiy V. B. Issledovanie geomekhanicheskogo sostoyaniya rudoporodnogo massiva v pole rudnika «Skalistyy» (Investigation of geomechanical state of ore-rock massif in the field of Skalisty mine). Gornyi Zhurnal = Mining Journal. 2010. No. 6. pp. 63–65.
15. Snelling P. E., Godin L. McKinnon S. D. The role of geologic structure and stress in triggering remote seismicity in Creighton Mine, Sudbury, Canada. International Journal of Rock Mechanics and Mining Sciences. 2013. Vol. 58. pp. 166–179.
16. Yakovlev D. V., Tsirel S. V., Mulev S. N. Zakonomernosti razvitiya i metodika operativnoy otsenki tekhnogennoy seysmicheskoy aktivnosti na gornykh predpriyatiyakh i v gornodobyvayushchikh regionakh (Development regularities and methods of operative assessment of technogenic seismic activity at mining enterprises and in mining regions). Fiziko-tekhnicheskie problemy razrabotki poleznykh iskopaemykh = Journal of Mining Science. 2016. No. 2. pp. 34–47.
17. Nesterenko Yu. M., Kosolapov O. V., Nesterenko M. Yu. Seysmicheskaya aktivnost rayonov razrabatyvaemykh mestorozhdeniy uglevodorodov v Yuzhnom Predurale (Seismic activity of mined hydrocarbon deposit regions in the Southern Cis-Ural region). Izvestiya Samarskogo nauchnogo tsentra Rossiyskoy akademii nauk = Proceedings of the Samara Scientific Center of the Russian Academy of Sciences. 2010. Vol. 12, No. 1(5). pp. 1240–1244.
18. Kozyrev S. A., Usachev E. A. Proyavlenie tekhnogennoy seysmichnosti pri proizvodstve massovykh vzryvov na podzemnykh rudnikakh otkrytogo aktsionernogo obshchestva «Apatit» (Appearance of technogenic seismicity during mass explosions on underground mines of the JSC "Apatit"). Vestnik Magnitogorskogo gosudarstvennogo tekhnicheskogo universiteta imeni G. I. Nosova = Vestnik of Nosov Magnitogorsk State Technical University. 2014. Vol. 17, No. 2. pp. 238–245.
19. Solovitskiy A. N. Monitoring geodinamicheskikh yavleniy razrushitelnogo kharaktera pri osvoenii mestorozhdeniy (Monitoring of destructive geodynamic phenomena during subsoil mastering). GEO-SIBIR-2010 : materialy Mezhdunarodnogo nauchnogo kongressa, 19–29 aprelya 2010 goda (GEO-SIBERIA-2010 : materials of International scientifi c congress, April 19–29, 2010). Novosibirsk : Siberian State Geological Academy, 2010. pp. 28−31.