The results of geomechanical studies to assess the rock burst hazard at the deposits (Kukisvumchorr and Apatite Circus) of the Kola Peninsula are presented in the article. These results are obtained by special set of technical means, including an automated seismic acoustic rock pressure monitoring system "Prognoz-ADS" and a portable geoacoustic device "Prognoz L" developed at the Mining Institute of the Far Eastern Branch of the Russian Academy of Sciences. Based on the measurement and analysis of the parameters of seismoacoustic events, reflecting the geomechanical processes in the mined rock mass, maps of seismoacoustic activity combined with 3D mining and geological models of mines were developed. Based on the analysis of the spectral parameters of the signals, it was concluded that the use of the developed software and hardware complex is promising for predicting dynamic phenomena in the rock massif. The rock burst hazard can be assessed by the measuring complexes at these deposits; necessary safety measures can be taken for decrease of geodynamic risk.
Underground development of mineral resources and mining construction in difficult mining and geological conditions and at increasing depths are associated hazard manifestations of rock pressure, both in statistical and dynamic forms. Rock pressure manifestations in hazard forms are displacement and collapse of areas of the massif, sudden outbursts of rock and gas, rock shots, rock and tectonic bursts leading to catastrophic consequences. A distinctive feature of the dynamic manifestations of rock pressure, especially rock and rock-tectonic bursts, is their suddenness and great destructive force. They cause great material and social damage to mining enterprises, lead to long stops in the mining process. It is caused by large-scale restoration work on large areas of the mine field. In terms of scale of negative consequences, powerful rock bursts can be attributed to man-made disasters [1-7].
There are a number of burst hazard ore deposits in Russia. JSC "Apatite" develops a number of deposits of apatite-nepheline ores, characterized by difficult geomechanical and rockburst hazardous conditions (figure 1). The object of research was two deposits: Kukisvumchorrsk ("United Kirovsk" mine) and Apatite circus (Rasvumchorrsk mine). Growth of depth of mining operations leads to an increase in the number and intensity of hazard phenomena. The high intensity of mining at these mines led to the formation of a vast zone of technogenic disturbance of the geo-environment, which was one of the reasons for the activation of geodynamic processes in the rock mass containing the mined deposits.