Cabanasses is an ore deposit located in the Catalan potash basin, whichis part of the Cardona evaporite formation in the Ebro Valley, 75 km northwest of Barcelona. The depositis configured by8 salt lithologies, formedby layers of clay-sized particles.Saline materials, under high stress,behave as a visco-plastic formcalled creep. This characteristic has a crucial influence to safety,production rate and costs. Therefore, it is necessary to study the properties of the salt lithologies as well as the characteristics of the clay-size particles, considering thesurfaces correspond to the weakness planesin order to find the best working conditions. Two different approacheshave been applied in this study:the laser scan and several geomechanical tests.The laser scan is a very useful tool to define the convergence of the drifts, obtaining a 3D model.Data from twodrifts was taken every week,called GC-01 and GC-02respectively. Three measurementsfor the GC-01 and four measurement for theGC-02, comparing the sections among them from week to week everymetre, using five control pointsin each section:1 on the roof, 2 on the roof corners and2 on the walls. The movements in all five control points were analysedin order to define the maindeformationmechanism. According to obtained results, it waspossible to observe the main deformation movement, seeing a considerable convergence displacement that reduces the cross-sections over time.In the caseof GC-01, the deformation increases progressively and homogeneouslywithout exceeding 2 cm per week in the 5 control points. WhileGC-02displays an irregular behaviour,either in the overall convergence or each individual point.Being more pronounced in the upper area, producing a flattened drift,wherethe deformations can exceed 10 cm per week.On the other hand, geomechanical testswere performed. Samples were collectedfrom each representative lithology of the mine, consideringthe potential weakness planes.Initially, roughness measurements were done in all the sample. Subsequently, the main geomechanical characteristics were analysed, such as natural and dry density, humidity and quantification of the insoluble particles of each lithology.These insoluble particles were analysed by several analytical techniques, using:theScanning electron microscopy (SEM) with analysis by energy-dispersive X-ray spectroscopy (EDS) and theX-ray powder diffraction (XRD). Obtaining information about the mineralogy of theircomposition, since the study of the mineral particles that form the joints is essential to understand the mechanisms ofthe stratarupture.The characteristics of the saline lithologies have been defined, providing a base to continue studying the saline behaviour in Cabanasses’ ore deposit. The study of the weakness planes has also provided useful information to increase the knowledge about the geomechanical behaviour of the ore deposit, as well as to understand that roughness could be a very important parameter to consider.
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