Geochemical baselines and prospecting of lithium in southeastern Brazil: low-density stream sediment mapping across Minas Gerais and the Araçuaí Fold Belt

Lithium (Li) is a strategic element in the global energy transition, largely driven by its use in lithium-ion batteries for electric vehicles. This study examines the distribution of Li and associated elements (Cs, Rb, K, Be, Sn) in Minas Gerais State, southeastern Brazil, through a low-density stream sediment geochemical survey combined with robust statistical approaches. Baseline values were defined using different calculation methods, multivariate statistics, and compositional data analysis, aiming to delineate Li-rich zones and evaluate the Araçuaí Fold Belt, a key domain of the Eastern Brazilian Pegmatite Province (EBPP). Results show that lithological diversity across the seven geotectonic units strongly controls geochemical baselines. The Araçuaí Fold Belt exhibits the largest concentration range and highest correlation coefficients between Li and related elements, reflecting a common source in pegmatites and parental granites. Among the tested methods, mMAD provided more consistent baselines and thresholds than TIF. Staged factor analysis (clr and ilr transformations) characterized main geochemical associations and supported the generation of the GMPI mineralization map, a predictive layer integrated into a Mineral Prospectivity Map (MPM). The study demonstrates how stream sediment geochemistry, treated with advanced statistical methods, can effectively guide mineral exploration strategies for critical elements such as lithium.