Preliminary Assessment of Salt Lake Brines for Lithium Potential in the Aral Sea Region, Kazakhstan

This study evaluated the potential of salt lakes in the Aral Sea region of Kazakhstan as lithium brine deposits.The Aral Sea region possesses favorable conditions for the formation of brine-type lithium deposits, such as an arid climate and a closed basin.However, critical features required for deposit formation (source rocks, fluid pathways) have not been identified.A total of 250 salt samples and 50 water samples (including brine, seawater, groundwater, river, and lake water) were analyzed from 14 salt lakes.Lithium contents in most salt samples were below the detection limit (10 ppm) or did not exceed the average crustal contents (20-70 ppm).The average lithium contents in water samples also ranged between 7 and 16 ppm, which is significantly lower than the 200 ppm generally considered economically viable for brine deposits.Furthermore, the brine exhibited unfavorable chemical compositions for lithium extraction, with high Mg/Li ratios (>1,570) and Na/Li ratios (>773).These results suggest that the salt lakes in the Aral Sea region have limited economic potential as lithium resources.However, the relatively high lithium contents observed in some lakes slimes indicate that further geological and geochemical investigations are needed to better understand local enrichment mechanisms and lithium sources.For a comprehensive assessment of the lithium potential, additional surveys including the southern part of the Aral Sea (in Uzbekistan) are considered necessary.