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中国三叠系蒸发岩分布于华南，面积超过１００×１０４ｋｍ２，发现硫酸钾盐及富钾卤水，钾盐矿物有杂卤石、无水钾镁矾、硫锶钾石及多钙钾石膏等，富钾卤水矿化度２５５～３８２ｇ／ｌ，含钾量４～４９ｇ／ｌ。蒸发盆地的发展受控于古构造及古地理，经历了开放台地—局限台地—堰塞湖—盐湖的发展阶段。钾盐沉积后，经历多阶段的复杂演变。富钾卤水中的钾主要来自硫酸钾盐的深滤，其次来自蒸发浓缩卤水及火山灰吸附钾的释放。杂卤石与富钾卤水的钾同位素测年值分别为２１０～１５０Ｍａ及２６４～１５０Ｍａ，说明固液相钾盐同源。从地质背景及成矿环境预测，三叠系的钾盐类型只能是硫酸钾盐，主要目的层为Ｔ１ｊ５～２及Ｔ２ｌ４～２，主要成矿带为构造分异及钾异常明显的四川盆地东、西部，富钾卤水的储集取决于蒸发岩地层的含钾性、碳酸盐夹层的裂隙发育程度及构造控矿条件。找矿模型应是油气钾卤兼探。
Triassic evaporites in China are distributed in South China with an area of more than 100 × 104 km2. Potassium sulphate and potassium-rich brine are found. There are polybasic halides, anhydrous aurons, strontium, potassium and gypsums, Potassium rich brine salinity 255 ~ 382g / l, potassium content 4 ~ 49g / l. The development of evaporative basins is controlled by paleotectonics and palaeogeography and has undergone the stage of development of the open platform - confined platform - dammed lake - salt lake. After the deposition of potassium salt, it undergoes multi-stage complex evolution. Potassium in potassium-rich brine comes mainly from deep-seeding of potassium sulfate salts, followed by the release of concentrated brine and ash adsorption by volcanic ash. The dating values of potassium isotopes of polyhalite and potassium-rich brine are 210 ~ 150Ma and 264 ~ 150Ma, respectively, indicating that the potassium-salt of solid-liquid phase is homologous. Based on the geological background and the metallogenic environment, it is predicted that the potassium type in the Triassic can only be the potassium sulfate salt, the main target strata are T1j5 ~ 2 and T2l4 ~ 2, and the major metallogenic belt is characterized by tectonic differentiation and obvious potassium anomalies The accumulation of potassium-rich brine in the eastern and western regions depends on the potassium content of the evaporite formation, the fracture development of the carbonate intercalation and the tectonic ore-controlling conditions. Prospecting model should be potash and exploration of oil and gas.