| Abstract: | The perspectives offered by using lithium as a pathfinder element in hydrogeochemical exploration for hydrothermal systems, even on a large scale, are discussed in the present paper.Approximately 200 natural water samples, coming for the most part from Tuscany, have been analyzed. The waters correspond to different geochemical conditions and/or processes, ranging from condensed steam from the Larderello geothermal fields to thermal springs, and from pyrite mine waters to stream waters.Lithium hydrogeochemical dispersion aureoles in the surface drainage system, originating from hydrothermal systems, are very marked and wide-spread. The Ombrone and Cornia rivers, in the basins of which thermal spring systems come to the surface, show marked lithium anomalies until the point where they merge with the sea.On the basis of the results achieved lithium appears to be the most specific pathfinder element, among the trace elements, in the hydrogeochemical exploration for hydrothermal systems. This element may, moreover, be utilized in large scale exploration by using a low density sampling, due to its high geochemical mobility in the surface environment.The results we obtained are furthermore of noteworthy importance with respect to the environmental geology, due to the link existing between the tectonic situation and the circulation of thermal fluids. The above topics are discussed in detail in the paper. |
