Characteristics and Distribution of Geothermal-Type Lithium Resources In Southern Tibet

Southern Tibet is one of the main distribution areas of China's high-temperature geothermal belt, with abundant hot water activities. There are 272 geothermal display areas, and 65 display areas with geothermal reservoir temperature higher than 150 oC. According to the results of field sampling and laboratory testing, it is found that the content of Li in the geothermal water in the high-temperature geothermal belts in southern Tibet is up to 34.51mg/l, the relative abundance of geothermal Li is significantly better than the salt lake brine of the three plateaus（the Andean plateau of South America, the western plateau of North America and the Tibetan Plateau of China）, and the ratio of magnesium to lithium is mostly less than 3, which is also significantly better than the salt lake brine. According to the material source of Li in the brine of lithium rich salt lake, the material source of Li in the high-temperature geothermal water in the southern Tibet is inferred. It is determined that there are two main material sources of geothermal water Li, which are caused by the leaching of lithium rich rocks by geothermal water and the lithium rich magmatic hydrothermal solution formed in the process of magmatic differentiation. The areas with high Li content in the geothermal water of the high-temperature geothermal zone in southern Tibet are distributed in the Yarlung Zangbo suture zone and its southern region, which has little to do with the distribution of high temperature geothermal zones and is consistent with the distribution range of lithium rich rocks. At the same time, the chemical type of geothermal water in the Yarlung Zangbo suture zone and its southern region is obviously more mature than that in the north. The more developed fault system brings more deep materials to geothermal water, which is also one of the reasons for the formation of lithium rich geothermal water.