Lithium sources in northern Puna salars, Argentina. Evidence from Li and Sr isotope compositions

FRIEDRICH LUCASSEN; SIMONE KASEMANN; ANETTE MEIXNER; RAUL BECCHIO; CARISA SARCHI; PABLO J. CAFFE

Hamburgo

Congreso; Latin-American Colloquium of Geosciences; 2019

Universität Hamburg

The Lithium-Triangle region is located in the high Puna-Altiplano Plateau of the central Andes (27° to 21° S). In this area, high-altitude endorheic basins (salars) contain the richest known brine resources of the Li in the world.In this work, we study Jama and Mucar salars (northern Puna). They developed within the same basin, separated by a range of Ordovician sedimentary rocks. With the aim of understanding the source of Li, we obtained Li and Sr isotopic ratios from rocks, brines, salts and river waters. Li isotope compositions reflect low temperature fractionation processes, during weathering or hydrothermal leaching of the source rocks, where Sr isotope ratios report contrasting signatures of potential source rocks e.g. Cenozoic volcanic and Ordovician sedimentary rocks.