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Purpose.This article proposes to analyze and determine the mining design for shallow-dip deposits hosted in poor quality rock. Methods. We used the UBC tool to find the optimal exploitation method, the Rock mass rating (RMR) and Q-system (Q) to determine the optimal mining stope and the recommended rock support, the numerical modeling by RS2 software with a variety of geotechnical, geometrical, and technical conditions to analyze the evolution of the unstable zone width and the maximum total displacement around the stope after excavation. Findings. The optimum mining method designated by the UBC tool for this type of deposit is the cut and fill. By projecting the obtained RMR and Q-system values on the design graph, it is concluded that the operating stope is located in the stable zone with a height of 3 m, and bolting support is recommended. The simulation by RS2 software reveals that the optimal mining design that can be used to mine shallow-dip vein deposits hosted in poor quality rocks consists of a 3 m high stope and a 75° dip with cemented backfill. Originality.This work presents a study to choose the most suitable underground mining method and mine design for shallow-dip deposits hosted in poor quality rock. Practical implications.In the mining industry, the success of operating an underground mine is conditioned by the selection of the appropriate method, of the mining design and dimensioning of a rock support adapted to the nature of the rock, and excavation geometry according to the type and nature of the deposit.

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The OUMJRANE mine located in the eastern Anti-Atlas in Morocco, is operating underground mining in various sedimentary rocks from sandstones to shales. During operation, several instabilities are recorded in the underground galleries. The present study represents an empirical characterization based on the classification index of the rock mass: RMR (Rock Mass Rating), Q (Tunnel Quality Index) of the stability of the excavation. The input data used for this analysis were based on fracturing surveys, core logging, and laboratory tests. The results of this study show that the rock mass is of low quality.

Data mining is a very important element that has been developing and evolving for years in the analysis and study of the stability of the underground gallery. More advanced methods, essentially empirical and statistical analysis are used to describe the rock mass of the OUMJRANE mine, in order to determine adequate support to be implemented in its underground gallery.