Migration and Accumulation Patterns of Potassium Salts in Brine from the Qaidam Basin and New Breakthroughs in Mineral Exploration
In China,potash resources are crucial strategic minerals that play a vital role in ensuring national food security.With the significant demand for and high external dependence on potash resources,there is an urgent need to explore new potash deposits and establish new large-scale potash resource bases.In 2023,the China Geological Survey organized geological surveys focusing on"increasing reserves and ensuring the supply"of potash resources in the Qaidam Basin,Qinghai Province.Building on a previous understanding of salt formation and potassium aggregation in the basin,the integrated drilling and exploration project,CK1 well,was successfully executed in Dalangtan-Heibei concave in the northwestern Qaidam Basin.The well penetrated a thick layer of loose sand and gravel brine reservoirs,reaching a depth of 1 021.95 meters(111.54-1 133.49 m).Pumping tests revealed a stable daily water inflow of 8 586 m3/d with a drawdown of 11.3 m and a specific yield of 759.89 m3/d·m.The average content of potassium chloride was 0.53%,representing a high-yield industrial-grade"sand-gravel type"potassium brine deposit.This achievement marks a significant breakthrough in deep-seated terrestrial brine potash resource exploration in the Qaidam Basin,laying a solid foundation for establishing a new billion-ton-scale potash resource base in China.