Assessment of seismicity level based on seismic energy flow distribution at deep levels of the Kukisvumchorr deposit

The article presents the results of studying seismicity during the advancement of mining operations to deep horizons using the case of the Kukisvumchorr apatite-nepheline deposit (the Khibiny massif). Mining of underground reserves of the investigated deposit is complicated by the presence of the Saamsky open pit and the adjacent Yukspor deposit. The study focuses on assessing the area distribution of the seismic event energy flow as the mining operations progress to deep mine levels. Zones of higher values of seismic energy flow density at the lower mine levels were identified as mining operations progressed to deeper levels and developed towards the Saamsky open pit. The results are presented as isoline maps, which helped to identify areas of different levels of seismic energy flow distribution. A classification of seismicity levels according to the seismic energy flow parameter was proposed for the conditions of underground mines of the Kirovsk Branch of Apatit JSC, i.e. the background, background elevated, high, and extremely high seismicity levels.