PHYSICS OF ROCKS AND PROCESSES | |
ArticleName | Change of state of rocks under transient loads induced by production blasting |
DOI | 10.17580/gzh.2016.10.05 |
ArticleAuthor | Grib N. N., Grib G. V., Imaev V. S., Tereshchenko M. V. |
ArticleAuthorData | Technical Institute (Branch) of the North-Eastern Federal University, Neryungri, Russia: N. N. Grib, Head of a Chair, Professor, Doctor of Engineering Sciences, grib@nfyqu.ru Institute of the Earth Crust, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia: V. S. Imaev, Chief Researcher, Professor, Doctor of Geological-and-Mineralogical
Yakutugol Holding Company, Neryungri, Russia: |
Abstract | Industrial development in South Yakutia is associated with the build-up of the mining production capacities. As a consequence, subsoil in the region increasingly suffers from large-scale blasting. To assess mining-induced seismicity, the authors have analyzed data of seismological monitoring carried out for ten years. In connection with the high natural seismicity in the region, mining drastically affects rock mass. Cyclical transient loads generated by large-scale blasts have direct and indirect effect on the upper earth crust. The direct effect is due to nonlinear displacements caused by blast waves and owing to generation of new dislocations. The indirect effects are from activation of structural elements at geological contacts. The increment in the mining-induced pressure on the geological and geophysical medium invokes irreversible seismic phenomena. Sources of induced seismicity are either closely spaced with a blast point, or locate north-westwards along an identified structure. Mining-induced impact transforms into an independent local seismic process. Production blasting initiates local trains of seismic events. In places, near-surface layers of the earth crust have activated in the zone of the dynamic effect of the Ammunakto-Muastakhsky and Nizhne-Neryungri active faults. From the viewpoint of energy, saturation of the earth crust with the blasting enegry and libration of the energy in the form of induced earthquakes are the forward and backward processes that should be in equilibrium in a closed system. It is found that mining-generated objects in the earth crust can interact with the faulting system created by natural seismo-tectonics. This means that a production-induced structure may show as a source of a to-be earthquake. Despite this fact, the total energy release per years before mining is higher, i.e. energy of earthquakes moves down. This result may mean that large-scale blasting has no considerable influence on the total energy balance of a seismo-tectonic process at an energy level above 1012 J. Consequently, blasting can both activate faulting in rock mass surrounding a mine and relieve seismic hazard sources initiated in the subsoil. |
keywords | Mines, rock mass, blasting-generated transient loads, induced earthquakes, seismic process |
References | 1. Wong I. G. Potential Injection-Induced Seismicity Associated with Oil & Gas Development: A Primer on Technical and Regulatory Considerations Informing Risk Management and Mitigation. 2015. p. 141. Available at: https://www.gwpc.org/sites/default/files/finalprimerweb.pdf (accessed: 05.10.2016). |
Language of full-text | russian |
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