The Principles of Evaluating the Risk of Rock and Gas Outburst in Copper Ore Mines

Rock and gas outburst is one of the most significant natural hazards faced by the mining industry. In the last decade, this issue has appeared in firm rock mining (including copper ore mines) in addition to coal mining. A number of methods have been developed for coal mining to assess the hazard posed by gasogeodynamic phenomena, but in the case of copper ore mines, no studies have led to forecasts of this risk. To face the challenge, the authors decided to propose their own concept of risk assessment principles based on a threshold analysis of the phenomenon and a continuous analysis using fuzzy logic. A series of tests were performed to support the paper, investigating selected parameters which directly affect the risk. The evaluation principles for gasogeodynamic phenomena presented herein were the result of experimental investigations carried out by the authors. Highlights The increasing frequency of gasogeodynamic phenomena in copper ore mines has led the authors to develop a concept for the principles of assessing gasogeodynamic phenomena in compact rocks. Research has been carried out to select parameters of the rock-gas system that strongly affect the occurrence of gasogeodynamic phenomena. On the basis of the performed measurements, two systems of rock and gas ejection hazard assessment have been proposed: a threshold assessment and a continuous assessment based on fuzzy logic. Analysis of the gasogeodynamic phenomenon hazard for places from which the examined rock samples originate was carried out. The results of the analysis and comparison of the assessment methods used are presented.