Abstract
A large number of lithium–potassium-rich brines have been found in Paleocene reservoirs in the Jianghan Basin, South China. First, the brines have exceptionally high lithium and potassium contents that are even higher than those in other closed basins on the Tibetan Plateau. Second, the enriched brines are widely distributed in the center of the basin. The Mesozoic and Cenozoic igneous rocks in the Jiangling depression are mainly basalt and granite, and their distribution area exceeds 50% of the basin. The large basalt body provided a thermal source for the water–rock reaction. The igneous rocks in the study area could have provided ore-forming elements, such as lithium and potassium, for the brine. A static immersion experiment at room temperature shows that fluids with certain salinities are more likely to activate K ions in basalt. However, weakly alkaline solutions more easily dissolve K. High-temperature water–rock experiments show that the dissolution rates of Ca, Mg, and Sr decrease with increasing temperature, while the dissolution rates of K and Li first increase and then decrease with increasing temperature. The dissolution of K and Li is easier when saline fluid reacts with volcanic rock. The dissolution rate of K is higher than that of Li in basalt, and the dissolution rate of Li is higher than that of K in granite. Compared with the results at normal temperatures, the ability of the fluid to leach elements at higher temperatures is significantly enhanced. Temperature is the main factor controlling the ability of fluid to leach elements. High-salinity fluid is the main carrier of ore-forming elements. According to the water–rock experiments, the mineral composition of the ancient brine in the Jiangling depression that formed during the Paleocene is consistent with that of the ore-rich brine found today, but different by a few orders of magnitude, indicating that the formation of lithium–potassium-rich brines requires a long time. The water–rock reaction is one of the important processes of brine formation, and surface evaporation and concentration are the main mechanisms of brine mineralization.
Highlights
In the SiO2 –(Na2 O+K2 O) diagram (Figure 5A), granite samples are plotted in the granite field, indicating that the magma around the Jianghan Basin has been differentiated to different degrees
In the SiO2 –K2 O diagram (Figure 5B), all the granite samples except the altered samples are plotted in the shoshonite series area, and all the other granite samples are plotted in the high-K calc-alkaline area
Acidic and alkaline rocks are favorable for the accumulation of lithium [49]
Summary
Modern salt lake brines and deep-buried underground brines are often rich in potassium, lithium, boron, rubidium, cesium, and other high-value strategic emerging mineral resources [1,2,3,4,5,6,7,8,9,10,11,12,13,14], and are important raw material sources of potash and lithium globally. Price et al (2000) [25] believed that lithium-rich brine in Clayton Valley Salt Lake, Nevada, western United States, may come from the weathering products of lithium-rich volcanic ash or rhyolite; Araoka et al (2013) [26] believed that lithium-rich intercrystalline brine of the dry salt lake in Nevada, United States, mainly came from high-temperature water–rock (volcanic rock) reaction and local hot spring activities, rather than from low-temperature weathering products of surface materials. The water–rock reaction process of basalt and granite was carried out by using a reaction kettle to explore its significance to the material source and genesis of the potassium–lithium-rich brine
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
