新疆库米什盆地硝酸盐类矿床成矿离子迁移规律及成矿模型  

Ore-Forming Ion Migration Regularity and Metallogenic Model of Nitrate Deposits in Kumishi Basin,Xinjiang

作　　者：李长忠 程怀德[1,2] 宋建国 马学海 海擎宇 蒋天明 Li Changzhong;Cheng Huaide;Song Jianguo;Ma Xuehai;Hai Qingyu;Jiang Tianming(Key Lab of Comprehensive and Highly Efficient Utilization of Salt Lake Resources,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining 810008,China;Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes,Xining 810008,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院青海盐湖研究所,中国科学院盐湖资源综合高效利用重点实验室,青海西宁810008 [2]青海省盐湖地质与环境重点实验室,青海西宁810008 [3]中国科学院大学,北京100049

出　　处：《地球科学》2022年第1期82-93,共12页Earth Science

基　　金：西北研究院“一三五”重点培育项目(No.Y760031090);科技部专项(No.2012FY112600)。

摘　　要：为了深入认识库米什盆地硝酸盐矿床成矿离子的空间分布特征、表层沉积物中硝酸盐含量较高的原因,以盆地硝酸盐矿床为研究对象,开展研究区内各类补给水样和沉积物样可溶性盐类物质化学组成的定量分析研究;结合野外地质踏勘工作,探讨研究区硝酸盐矿床成矿离子的迁移规律,初步建立盆地硝酸盐矿床沉积成矿作用模型.结果表明,K^(+)、Na^(+)、NO_(3)^(-)等成矿离子自北西部和南东部双向朝盆地中部迁移富集;这些成矿离子的含量在盆地北东部冲洪积扇区沿着基岩区‒扇根‒扇中‒扇缘的方向逐渐增高,在扇缘的表层沉积物内含量较高;在垂向剖面上,K^(+)、Na^(+)、NO_(3)^(-)等成矿离子主要富集于0~60 cm的深度范围内,受毛细作用的影响,具有自深部向表层沉积物内迁移富集的规律.In order to understand the spatial distribution characteristics of ore-forming ions and the reason for high nitrate content in surface sediments of nitrate deposits in Kumishi Basin.In this study it focuses on the nitrate deposits in the basin,and a quantitative analysis of the chemical composition of soluble salts in various make-up water samples and soil samples was carried out in the study area.Combined with field geological exploration work,the migration regularity of ore-forming ions in nitrate deposits is discussed.Besides,a model of sedimentary mineralization of nitrate deposits in the basin was established.The results show that ore-forming ions such as K^(+)、Na^(+),and NO_(3)^(-)migrate and enrich from northwest and southeast toward the middle of the basin.The concentrations of K^(+)、Na^(+)、NO_(3)^(-)and other ore-forming ions gradually increase along the direction of the bedrock area⁃fan root⁃middle fan⁃fan margin in the diluvial fan in the northeast of the basin,and enrichment occurs in the surface sediments at the fan margin.In the vertical profiles,K^(+)、Na^(+),NO_(3)^(-)and other ore-forming ions mainly show migration and enrichment in the depth range of 0-60 cm.Under the influence of capillarity,they migrated and enriched from deep to surface sediments.

关 键 词：库米什盆地 硝酸盐矿床 成矿离子 沉积成矿作用模型 毛细作用 矿床学 

分 类 号：P612[天文地球—矿床学]