Lithium Deposits from the Mesoarchean to the Present: Their Types, Distribution in Time, and Explored Resource Base

The distribution of lithium deposits and lithium resources contained in them are analyzed throughout geological time. The basis for the analysis is data on 164 deposits from around the world with resources estimated above 100 thousand t of Li2O, representing almost the entire explored resource base attractive in the modern and near future conditions to extract this element. The variability of various aspects of their formation in geological time is demonstrated by comparing supercontinent cycles in terms of the quantity and quality of resources in deposits of different types, ages, and tectonic position. It has been established that lithium deposits have an extremely uneven pulsed distribution on the geological time scale. The Kenoran, Columbian, and Rodinian cycles are represented only by the pegmatite-type deposits, the intensity of formation of which decreased in this series. In the Pangean cycle, it increased again, approaching the Kenoran level. In addition, first deposits of a granite type appeared. In the current Amasian cycle, deposits of the granite type quantitatively predominate over the pegmatite type, but they both yield quantitatively to the clay-type deposits only appeared in this cycle. In terms of the resources, all these three types with solid ores are inferior to deposits associated with brines in salars, geothermal and oil-and-gas fields. All deposits from the Kenoran to Pangean cycles were formed in collision belts at the postorogenic stage of their development. In the Amasian cycle, continuity in this aspect was preserved, but deposits of granite and clay types formed in the back zones of active continental margins were also established. Deposits in salars also have these two tectonic positions. Geothermal deposits are known within the framework of collisional orogens and on active continental margins. Oil-and-gas fields have been explored only in the sedimentary covers of ancient platforms. Currently, objects of pegmatite and salar types are of maximum importance for the world economy, and the granite-type deposits are of less significance. All of them are traditional for lithium extraction. In the pegmatite type, the Kenoran deposits have the highest degree of industrial development, in the granite-type deposits of the Amasian cycle. In recent years, single deposits of clay, geothermal, and oil-and-gas field types began to be involved in the exploitation, as well as representatives of the salar type with brine compositions that have not been suitable for conventional technologies.