This paper studies the rock mass stress state of deposits under highland conditions, depending on the geological structure of a particular rock mass area, the tectonic field of stresses and the region relief. This study is aimed to develop an experimental method for assessing and monitoring the properties and state of the rock mass adjacent to mine workings. Experimental studies are performed through stresses measurements in-situ. Based on research results, it has been revealed that the geological structures, tectonic fields of stresses and the earth’s surface relief of the deposit normally reflect the values and direction of the main stresses acting in the rock mass. These patterns can be used to predict and assess the stress state of the rock mass. During the rock mass stress state assessment, quantitative dependences have been obtained for determining the stress tensors conditioned by the overlying rocks weight, tectonics and fracturing, and the deposit surface relief The research results make possible to assess the nature of the stresses distribution, to identify the areas of reduced, equal, increased and maximum stresses concentration of the virgin rock mass, as well as to increase the efficiency of the geoacoustic control developed by the authors for the state of the rock mass adjacent to mine working.

This article focuses on the complex processing of quarry tuffs-stone to extract metals (iron, titanium, copper, silver, etc.) and obtain raw materials for construction and agriculture. The issue of tuff-stone softening was investigated and the analytical dependence of the regularity of tuff-stone softening at water saturation was established, which indicates that the saturation increases with increasing mass of the sample according to the logarithmic law, and the dehydration process occurs according to the parabolic law. Also in the course of researches the magnetic susceptibility of tuff-stone was defined, which depends on size of induction of a magnetic field. The magnetically sensitive part is up to 50% by weight of the sample, and the remaining silicate part at a magnetic field strength of 1.3 Tesla. Spectral analysis showed a high content of metals in the magnetically sensitive part of tuff-stone, which consists of iron (35-40%), titanium (2.5-4.0%) and copper in the silicate part (0.4-0.7%). It was found that the percentage of content representing commercial interest, and therefore it is appropriate complex processing.

The article presents basic information about the method of hydromechanical extraction of amber from amber-containing rocks, water-sludge scheme and classification scheme. The constructive scheme of the vibroclassifier is also presented, which is based on the principle of using the influence – vibration and bubbling of the suspension by air bubbles. Studies of the separation process and distribution of fractions in multidisperse liquid on a vibroclassifier of complex action were performed. The obtained theoretical and graphical dependences allowed to establish changes in the parameters of the velocity of sand and amber particles in the bath of the vibroclassifier on the size of fractions and density of the suspension, focusing on the size of amber up to 5mm. At the same time, the problem of determining the dependence of the transition coefficient from the rate of free to the rate of compressed deposition on the density of the suspension and the size of the fractions was solved. Dependencies have been established that have a theoretical justification for the physical process and that describe the experimental data on the Rayleigh curve.

Ventilation when driving roadways is one of the most important considerations in coal underground mines. Ventilation efficiency depends on fan performance and ventilation ducting system. In recent years in Vietnam, ducts have often been produced domestically. However, parameters of the duct as duct leakage, duct resistance for designing auxiliary ventilation system are referenced from abroad handbook. This lead to inaccurate design results and needs to adjust efficiency of auxiliary ventilation during driving roadways. Determination of duct resistance; air leakage in ducting system have been undertaken. The research result has been used to optimize the auxiliary ventilation system.

Methane reserves of coal mines of Ukraine are analyzed, and comparisons with other coal mining countries of the world are made. It is determined that Ukraine is among the countries with the largest reserves of mine methane. Data on the need to reduce methane emissions and its negative impact as one of the main greenhouse gases on global warming and climate change are presented. The world experience of methane extraction and processing from coal mines is studied, the advantages and disadvantages of different types of methane neutralization are determined. The priority directions of this activity for Ukraine are determined.