Qianjiang depression is one of the important Paleogene potassium-bearing brines deposits.Based on detailed field geological investigation, two-dimensional and 3D seismic interpretation, logging interpretation and chemistry analysis,this paper studied the reservoir characteristics,brines forming regularity,geochemical characteristics and deposit genesis.Potassium-rich brine occurs mainly in the Qianjiang Group with an area of 1630 km2 .The hydrochemical type of brines is mainly sodium-sulfate subtype,with salt-water system of Na,K//Cl,SO4-H2 O,and is secondarily calcium-chloride type, magnesium-sulfate subtype and carbonate type.The average salinity of brines is 280.94 g/L and pH value is between 9 and 5.The reservoir of brines is sandstone,thus the distribution of brine is mainly controlled by the distribution of sandstone body.The burial depth of the brines group floor shows the distribution feature of “one depression with two slope”,and the cumulative thickness of the brines ore body is gradually thinning from north and south. It center on syncline along the east-west direction, the cumulative thickness has gradually increased to the east and the west.The brines distribution is closely relatecl to ancient landform of depositional period on the plane.The brines salinity is maximum in Banghu, Wangchang and Zhouji that are the settlement center of syncline,and the contents of KCl,B2 O3 ,LiCl and Br are relatively higher,which reaches the grade for comprehensive utilization.%潜江凹陷富钾卤水矿床是我国古近纪重要的卤水矿床之一，本文在详细的野外地质调查基础上，结合二维、三维地震解译，测井解译，室内化学分析，研究了该矿床储层特征、卤水赋存规律和地球化学特征，探讨了其矿床成因。富钾卤水主要赋存于古近系渐新统潜江组，含矿面积达1630 km2，水化学类型主要为硫酸钠亚型，次为氯化钙型、硫酸镁亚型和碳酸盐型。卤水总矿化度平均值为280．94 g／L，酸碱度在5～9之间。卤水储集体为砂岩，卤水矿床的分布主要受砂体展布的控制，各卤水组底板埋深表现出“一洼两斜坡”的展布特征，矿体厚度自北而南累积厚度减薄，东西方向以向斜为中心，累积厚度向东或向西逐渐增加。在平面上与沉积时期古地貌密切联系，在蚌湖、王场和周矶向斜沉降中心卤水矿化度最大，氯化钾、B2 O3、LiCl、Br 等微量元素含量相对较高，达到综合利用或工业品位。
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