ABSTRACT
Potassium resource is very scarce in China.At present, it has been proved that many reserves of the potassium resource are mainly distributed in salt lakes, and most of them are in Qaidam basin (Wang et al. 2007, Wang et al. 1997). Mahai potash area is located in the eastern part of the North Qaidam basin in Qinghai province, at N38◦12′18′′–38◦23′38′′ and E94◦00′35′′– 94◦21′21′′. It is located in the Cold Lake town of the Mongolia Tibetan autonomous prefecture of Haixi state in Qinghai province. There is solid and liquid potassium resource in Mahai potash area, which is a quaternary saline lake deposit with potassium, sodium, and magnesium component elements. Now, the solid potassium on the earth surface was completely exploited in Mahai potash area. So the new mining production is ongoing by dissolving the lowgrade solid potassium rock. The hopper of decreasing pressure has appeared in an unconfined aquifer. The average decrease of the hoppers is about 2.40 m, and
the maximum decrease exceeds 5.00 m near the channels for collecting brine. So the reserves of brine in unconfined aquifer decreases gradually. It is urgent to increase the mining amount of brine to keep a continuous and stable production. As to the resource bottleneck of brine mine, the exploiting of pressure brine is the inevitable choice for sustainable development. And the pressure brine will be one of the most important resources in the future.
