Factors of seismic behavior change and localization of hazardous zones under a large-scale mining-induced impact

Abstract

Large-scale mining operations over 90 years at the Khibiny apatite-nepheline deposits that are characterized with the conspicuous gravity-tectonic type of the stress-strain state have transformed the initial stress field of the rock massif, which has led to the recurrent occurrence of rockbursts. This problem retains its relevance due to constant increasing intensity of mining operations at the apatite mines during the last two decades and complicated mining, geological and geomechanical conditions. Accordingly, the dynamic rock pressure is increasing. We have retrospectively analyzed data on the manifestations of geodynamic events in the Khibiny rockburst-hazardous deposits and determined a set of factors that influence the changes in seismic behavior and localization of hazardous zones in complicated mining and engineering systems. We have systematized the data of long-term observations on dynamic rock pressure manifestations at the Khibiny apatite mines, taking into account the seismicity parameters, the scale of mine damage, the mining-induced stress fields, and geological and geomechanical features of the rock massif at specific time points. A structural scheme has been developed and ranking of factors has been carried out, considering the time of impact on the rock massif.