Lithium and gallium abundance and enrichment factors in typical Late Permian coal-accumulating basin in Guangxi

Through systematic sampling and testing of two typical Late Permian coalfields in Fusui and Xian'an, starting with the lithium and gallium abundance of the samples, and combining with the metallogenic geological background of the Late Permian coal-accumulating basin in Guangxi, the factors controlling the enrichment of lithium and gallium in coal are analyzed. The results show that lithium and gallium in coal of both coalfield have certain industrial prospect. Lithium is mainly concentrated in K₁ coal seam, carbonaceous mudstone and bauxite section at the bottom of Heshan Formation, while gallium abundance in each lithology at the bottom of Heshan Formation is not significantly different. The intermediate-acid volcanic rocks in the Yunkai paleocontinent and its surrounding areas are the basic source of lithium and gallium in the Late Permian coal measures in Guangxi. The high-aluminium sedimentary rocks at the bottom of the Heshan Formation may be the direct source of lithium and gallium in the K₁ coal seam of the Heshan Formation. The migration of gallium between rock bodies is relatively active, so the content level of provenance plays a leading role in many enrichment factors. Besides provenance, lithium enrichment is more obviously influenced by sedimentary environment and later geological processes. The study result provides a scientific basis for the exploration, prediction and comprehensive utilization of lithium and gallium resources in coal measures in Guangxi.