Numerical analysis stability of a geothermal plateau in the field “Los Azufres” Mexico

This paper presents a study of a geothermal plateau that houses a well and a cooling stack, in which were identified slope stability problems. Zone was geologically characterized to describe lithology of the area besides, mechanical, physical and in situ tests were performed and from those, a geotechnical profile was proposed. Numerical analysis were carried out considering different conditions: static, pseudo-static, saturated material and degradation of the rock, for review and define the most unfavorable state. Software used in analysis was the Slide® from Rocscience in two dimensions (2D), considering the Hoek-Brown and Mohr-Coulomb failure criteria, to reproduce behavior of the materials according to its geotechnical characteristics. Results show that for current conditions and with the defined geotechnical parameters, the analyzed zone is stable for local and general failure mechanisms, being the safety factors (SF) greater than the admissible ones, according with the stability criteria taken in this study. However, for areas in which there is a mass degradation of the surface materials and, which are susceptible to the saturation, resulting safety depth is less than admissible and there is a risk of mass wasting encompassing since a few centimeters until meters of depth. Finally, some recommendations to stabilize the medium are proposed, according to the established analysis in this study.