新疆库车坳陷西段膏盐层沉积、地球化学特征及找钾方向  

Sedimentary-Geochemical Characteristics and Potash-Prospecting Potential of Gypsum-Salt Layer in Western Kuqa Depression

作　　者：王凡 邓小林[3] 郑绵平 韦钊[2] 王淑丽 赵玉海 刘星旺 王占文[2] Wang Fan;Deng Xiaolin;Zheng Mianping;Wei Zhao;Wang Shuli;Zhao Yuhai;Liu Xingwang;Wang Zhanwen(Institute of Mineral Resources,Chinese Academy of Geological Science,Beijing 100037,China;Geology Institute of China Chemical Geology and Mine Bureau,Beijing 100101,China;China Chemical Geology and Mine Bureau,Beijing 100013,China)

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]中化地质矿山总局地质研究院,北京100101 [3]中化地质矿山总局,北京100013

出　　处：《地球科学》2022年第1期56-71,共16页Earth Science

基　　金：中国地质调查局项目(Nos.DD20160054,1212011220790);国家重点研发计划课题(No.2017YFC0602806)。

摘　　要：库车坳陷西段深部(5141~5218 m埋深)已有古近纪固体钾石盐矿(化)层的发现,但对该区域的膏盐层特征及成钾条件、找钾方向仍需做进一步的系统研究.以油气钻井深部膏盐层岩屑为主要对象,对库车坳陷西段膏盐层的沉积、岩石学特征以及钾、溴氯系数、Sr和S同位素等地球化学特征进行研究,并对该区盐构造特征及演化进行分析.结果表明,钾及溴氯系数指示秋里塔格构造带以南羊塔-却勒一带成钾条件良好;库姆格列木群膏泥岩段-白云岩段-膏盐岩段沉积特征、钾、溴氯系数以及Sr和S同位素特征指示秋里塔格构造带以北的大北等区域存在潜在成钾区;库姆格列木群砂砾岩段-膏泥岩段沉积特征及盐构造演化分析均表明羊塔-却勒一带可能在成盐期为有利成钾的次级凹陷,且后期保存较好.综合分析认为库车坳陷西段秋里塔格构造带以南羊塔-却勒一带成钾条件最为有利,且北部存在多个包括大北区在内的找钾远景区.The Paleogene solid potassium salt mineralization has been found in the deep layer(5141-5218 m)of western Kuqa Depression,but it is still necessary to further study on the characteristics of gypsum-salt layer,potash conditions and potashprospecting in the region.Taking the gypsum-salt layer debris in deep oil and gas drillings as object,in this paperit performs research on sedimentary and petrological characteristics of gypsum-salt layer,as well as potassium content,bromine-chlorine coefficient,Sr and S isotopes and other characteristics in western Kuqa Depression.Besides in this paper it also analyzes the salt tectonic characteristics and evolution in the region.The results show that the potassium and bromine-chlorine coefficients are good in Quele-Yangta belt in the south of the Qiulitage tectonic zone,which proves to be a good condition for potash formation.Sedimentary characteristics of Kumugeliemu Group,potassium content,bromine-chlorine coefficient,Sr and S isotopic characteristics indicate the potential potassium formation in the Dabei area,north of the Qiulitage structure belt.Sedimentary characteristics of Kumugeliemu Group and the analysis of the salt structure evolution reveal that Quele-Yangta belt is a favorable secondary depression for potassium in the salt-forming period,which is better preserved in the later period.It is considered that Quele-Yangta belt which is located in the south of Qiulitage tectonic zone in the western Kuqa Depression is the most advantageous area for potassium exploration,besides,there are several potash prospecting areas in the north of Qiulitage,including Dabei district.

关 键 词：库车坳陷 沉积学 岩石学 地球化学 盐构造 钾盐 

分 类 号：P619.211[天文地球—矿床学]