La Candelaria Ridge (NW Argentina) as a natural lab for the exploration of the geothermal system of Rosario de La Frontera:methods and preliminary results

Within the scientific framework recently proposed by C.U.I.A. (Consorzio Universitario Italiano per l’Argentina) for the development of applied researches on the Argentina territory, several research groups, belonging to selected Italian and Argentina Universities, converged in the last year on the research line devoted to the “Sustainable development of future towns”. This contribution focuses on the preliminary results achieved by this collaboration among the Universities of Camerino, Jujuy, Roma Tre, Salta, Sapienza. The project focuses on the application of robust methodologies and the development of new ones to explore the geothermal potential of the area of Rosario de La Frontera (NW Argentina) located at the northern edge of La Candelaria Ridge, one of positively inverted structures cropping out between the provinces of Salta and Tucuman. It belongs to the Santa Barbara System of the Andes retro-wedge. This approach intends to contribute to the sustainable development of the town of Rosario de La Frontera, that can be potentially based on the exploitation of medium enthalpy (90°<T<150°C) geothermal resources. The main goals of this project are:  To constrain the origin of the geothermal anomaly that affects the study area by means of the reconstructions of the paleo-thermal, geochemical and morpho-structural evolution of La Candelaria Ridge. The first type of reconstruction is approached by means of 1D modeling of indicators of thermal exposure (e.g. vitrinite reflectance, clay minerals geothermometers and Th and Tm from fluid inclusions). The second is based on hydro-geochemical and isotopic investigations on waters sampled in the sites of thermal springs. The third is based on quantitative elaboration of aerial photos;  To evaluate the size, fracture network and permeability of the potential geothermal reservoir and effectiveness of its caprock by means of traditional structural analyses at different scales and combined deterministic-stochastic reconstruction of the fracture network with the aid of dedicated software;  To identify the recharge areas and deep fluid flow by means of geological and geophysical investigations (namely based on audiomagnetotelluric survey);  To model the geothermal system. The preliminary results related to the first three aforementioned objectives are presented in this scientific session with a series of companion posters. We present the preliminary analytical and modelling results concerning the paleo-thermal conditions recorded by the sedimentary succession cropping out along La Candelaria Ridge