The study area is characterized by a tabular to lenticular quartz vein with an average thickness of 1.5 m, gently dipping 20 °, extracted by the room and pillar mining method. In a certain location of the mine, the first evidence of floor puncture features was identified, represented mostly by cracks and protrusions longitudinal and oblique to the sills of the production drifts, followed by statements of spontaneous mass loss in the pillars. A detailed review of the geological information made

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... ossible to formulate a relationship between the unstable region and a local 5-meter-thick layer of Talc schist underneath the base of the pillars. The deformations, failures and settlements of sill and pillar base in this low strength rock mass was then compared to the concepts of load-bearing capacity for shallow squared foundations in Soils. due to the particularities of the excavation formats such as shanty back drifts, asymmetric, and anisotropic pillars, the study performed a strain-stress analysis by three-dimensional finite element numerical modeling, to offer a closer estimate of the behaviors observed in the field.