The results are presented related to the retrospective analysis of the stability of Tyrnyauz deposit massifs during combined open-cast and underground mining for the development of measures to improve occupational safety. The information about Russian reserves of the tungsten and molybdenum is given. The characteristics of Tyrnyauz tungsten-molybdenum deposit and technologies for its development in the historical cross-section are provided. The distinctive features of the development of high-altitude deposits are described on the example of the Caucasus. Brief information is given on the method of measuring the displacement deformations of the mined ore mass by geometric leveling using profile lines of the reference marks. The result of the experience of the deposit combined development and the idea of the rock mass as a heterogeneous medium of structural blocks limited by the fractures in the form of agitators with the glide planes and filling with the secondary material are formulated in the article. The methodology is given concerning identification of the regularities of the massif deformation based on the data of surveying measurements with the location of reference marks on the surface, at the bottom of the open-cast and in the underground horizons with graphical construction of hazardous zones. Information about the mechanism of destruction of the massif is generalized and systematized differentially for the composing elements: Blind deposit, Main scarn, Mukulansky open-cast It is shown that the deposit is located in the zone of tectonic forces effect, the stress state of its massif differs from geostatic in magnitude and direction of stresses, genesis and technogenic changes facilitated the transformation of the ore massif into a discrete medium, the formation of voids in the rock massifs was accompanied by the development of deformation with massif destruction. Studies of the history of the development of Tyrnyauz deposit testify the adequacy of massif behavior during technogenic intervention, which is a prerequisite for optimizing the technologies for industrial development of the deposit with an economic and environmental benefits.
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