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

V. P. Marysyuk, Director, Candidate of Engineering Sciences, marysyukvp@tf.nk.nornik.ru
M. V. Tereshchenko, II Category 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 considers approaches to estimating seismic activity and regional rockburst hazard in Skalistaya mine field. It is shown that the procedure recommended for the mine seismic station ISS and based on the ratio of seismic energy and seismic moment (overall energy) is low-efficient in assessment of seismic hazards. Probably, the reason is a wide variety of dynamic events in the mine, including events omitted in the Brune model. Therefore, the procedure accepted in the mine is based on the integrated index F and is used in other mines of the Polar Division of Norilsk Nickel, where seismic monitoring employs seismic stations Relos. The intergated index F involves three seismic parameters — number of seismic events; seismic deformation determined using the Benioff method; and slope of frequency plot of seismic events. Aiming to improve efficiency of the index F to be used by seismic stations of different type, a detailed analysis embraces the relation between the values of F and the linear size L of a cell of a mesh to represent rock mass in calculation of F. According to the results, under conditions of Skalistaya mine, the maximum value of F linearly depends on the area of cells of the mesh representing the area under study, F = b_L·L. As a rule, large seismic events are preceded by an increase in the coefficient b_L and by a rise in the ratio of F of the overall area to F in the most active zone, and then follows a certain decrease in bL in the most hazardous zone.

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