Geological settings and metallogenic conditions of the granite-type lithium ore deposits in South China

South China is an important base of granite-type Nb-Ta-Li-rare metal and rare earth ore deposits in China, which are characterized by granite-type, altered-granite-type and local pegmatite-type rare metal ore deposits. These ore deposits are distributed mainly in the Nanling, Jiangnan and Wuyi orogenic belts. Most Lithium ores are dispersed in the rock and co-exist with Be-Cs-Nb-Ta rare metal elements. Based on previous research, we analyzed and studied geological settings and minerogenetic conditions of thegranite-type Nb-Ta-Li-rare metal resources in South China. Studies suggest that the geotectonics of the South China Block strictly constrains the distribution of lithium ore zones, and that the formation and enrichment of Nb-Ta-Li-rare metal elements occurred in the mature continental crust with ancient basement. The enrichment of granite-type Nb-Ta-Li-rare metal elements experienced multi-period reworking of regional-scale tectonism and granitic magmatism and polyphase ore-material cyclic process. The high-matured crust, the high-differentiation and high-evolution granitic magma and the metasomatism and alteration of F-Cl-B-Na-H2O-rich fluids are three key factors leading to migration and enrichment of Nb-Ta-Li-rare metal material. Most lithium ore deposits were distributed in the late-stage pluton, the altered granite and the pegmatite within a composite pluton, and located in the axial zone of anticline and the junction of two-group faults in the orogenic belt. The Li-Nb-Ta-rich ore deposits always occur in the top and marginal parts of the late-stage pluton. In South China, the lithium mineralization was concentrated in the Neoproterozoic, Late Ordovician-Silurian, Early-Middle Triassic and Late-Jurassic-Early Cretaceous periods, and the large to huge-type Li-bearing ore zones occur in the Late-Jurassic-Early Cretaceous granitic plutons. The South China possesses a preponderance of granite-type Li-Nb-Ta-rich ore deposits and has ambitious prospecting potential. © 2021, Science Press. All right reserved.