CONICET | Buscador de Institutos y Recursos Humanos

The Andean plateau is a small region of South America extending between northwest Argentina, southwestBolivia, and northern Chile. It concentrates the largest global resources of lithium brines in its numerous salars.Of these, the giant salars in Bolivia and Chile have been relatively well studied; however, only little is knownabout the smaller but numerous salars in the Argentine Puna region. In this article, we present the results of thefirst regional-scale reconnaissance exploration of the 12 major salars situated in the southern part of the Punaplateau (24°S?26°30?S). Hydrochemical data indicate that the shallowest brines are characterized by highly variableLi concentrations, with mean Li grades ranging between 57 and 570 mg L?1, and mean Li/Mg ratios from0.01 to 1.24. A survey of the brine chemistry of the salars across the Puna plateau, including its northern part,has revealed the absence of a geographical pattern in Li+ grade distribution. However, a comparison amongmean Li+ grades, Li+/Mg2+ ratios, and the sizes of all salars allows an estimation of their Li mining potential.Specifically, the salt pan of Arizaro represents the highest potential, mainly due to its size; Antofalla-Botijuelashas a large surface and promising Li/Mg ratios for Li recovery via brine evaporation, though its elongated shapeis a constraint; and Pastos Grandes, Pozuelos, and Rincón have encouraging Li grades, interesting salar sizes,and relatively easy access. Olaroz, Cauchari, and Hombre Muerto contain the highest Li+ grades in brines of theArgentine Puna and embody the most interesting perspectives of the Argentine plateau in a regional context.Salar sizes could be related to maximum Li+ grade of brines. Larger salars would then be expected to containbrines with higher Li+ grades than smaller ones, which could be considered as a useful criterion for surveys ofbrine-type deposits.