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Purpose. This paper deals with the determination of the regional stress field direction of the Bou Azzer inlier using the remote sensing tool. Methods. CIn this study, we use an approach to digital mapping by remote sensing, including the steps of pre-processing and processing of Landsat-8 OLI images. Then, an automatic extraction of lineaments based on directional filtering has been performed. To determine the main directions of major mean fractures, these results have been supplemented and confirmed by an integrated model, including a synthesis of bibliographic works and field studies. Findings. The directional rosette analysis results show four systems of major directions namely, N0°, N45°, N90° and N135°. The regional stress field in the study area, according to tectonic history, is characterized by a horizontal compression tectonic regime, as indicated by several systems of strike-slip faults with a high tendency to deformation. Thus, the abundance of brittle and ductile microtectonic indicators confirms the direction of the main compressive stress N°30. The direction of the three-dimensional stress field: σ1: N°30, σ2: N°120, σ3: Vertical component. Originality. The present study allows to determine the regional stress field direction of the Bou Azzer inlier, in particular, in areas affected by complex tectonics of various scales, as well as in hard-to-reach areas. Practical implications. In mining practice, the study of stability using 2D and 3D geotechnical numerical modeling of underground mine workings is essential. The stress field direction is an important input parameter to develop more realistic decision support models, as well as to ensure the safety of people and materials at the Bou Azzer mine.

Purpose. The Bou Azzer Mine encounters difficulties during cobalt mining. In order to select the optimal mining sequence with the least geotechnical stability problems, one possible variant is the cut and backfill mining method used in the Bou Azzer East area at a depth of 540 m. Methods. This paper presents a methodology for selecting a sequence of the cut and backfill mining method using 2D geotechnical numerical modeling, taking into account the morphological characteristics, geomechanical properties of the ore and the surrounding rocks. Findings. The sequences of mining with rock backfill and rock-cemented backfill show that the high principal stress (Sigma 1) is in the range of 10-153 MPa, and the safety factors are in the range of 0.63-1.89. Therefore, mining sequences with cemented backfill and under cemented backfill have a principal stress (Sigma 1) in the range of 10-112 MPa and acceptable safety factors. Originality. In this study, the bottom-up mining sequence with a cemented backfill is proposed for the case of low-quality serpentine footwall. This mining sequence aims to achieve good cobalt mine production and provides a safe environment for miners. Practical implications. In the mining industry, the choice of mining method using 2D or 3D geotechnical numerical mo-deling is important to ensure the safest and most operational mining sequence in the mine lifetime.