Lop Nur salt lake deep potash scientific drilling Well 2 （LDK02） has a completion depth of 1200m， which is the first deep potash parameter well in Lop Nur salt lake district. The successful application of loose layer coring， high salinity brine drilling fluid， and closed depth sampling technology has solved malignant wellbore accidents such as easy shrinkage and sticking of drilling in gravel and sand layer coring， unstable block falling and collapse of drilling fluid salt immersion wellbore. The same diameter sealing process simplifies the drilling structure； The fixed depth sampling technology maintains the relative stability of the original components of the water sample， laying the foundation for studying the distribution and spatiotemporal evolution of potassium rich brine at different depths in this area.