青藏高原湖泊中影响锂元素迁移和富集的矿物、元素及环境因素--以西藏郭扎错钻孔沉积物为例  

Minerals,Elements and Environmental Factors Affecting the Migration and Enrichment of Lithium in Qinghai-Tibet Plateau Lakes:A Case Study of Sediments in Gozha Co Borehole,Tibet

作　　者：李明慧[1] 朱立平[1,2] 王晓晓 鞠建庭 聂小芳 LI Minghui;ZHU Liping;WANG Xiaoxiao;JU Jianting;NIE Xiaofang(Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100101,China;State Key Laboratory of Tibetan Plateau Earth System,Resources and Environment(TPESRE),Institute of Tibetan Plateau Research,Chinese Academy of Sciences(CAS),Beijing 100101,China;College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China)

机构地区：[1]中国科学院青藏高原研究所,北京100101 [2]中国科学院青藏高原研究所,青藏高原地球系统与资源环境全国重点实验室,北京100101 [3]山东科技大学地球科学与工程学院,山东青岛266590

出　　处：《中国无机分析化学》2023年第7期714-722,共9页Chinese Journal of Inorganic Analytical Chemistry

基　　金：第二次青藏科考项目(2019QZKK0202);国家自然科学基金资助项目(41831177);中科院先导专项项目(XDA20020100,XDA20070101)。

摘　　要：作为我国战略性矿产的锂矿,主要赋存于青藏高原盐湖中。湖泊系统中,锂的富集和迁移规律关系到锂矿的高效提取和未来锂矿的储量估算。以西藏咸水湖郭扎错的钻孔沉积物为例,结合AMS 14 C年代和Mg元素含量变化,系统分析了孔隙水、碳酸盐矿物和硅酸盐矿物的锂含量变化,探讨了矿物、镁元素、环境变化和早期成岩作用等对锂元素迁移和富集的影响。郭扎错沉积物中锂和镁大部分存在于硅酸盐矿物中,锂和镁较高的相关性说明二者存在于相同的硅酸盐矿物中,如黏土矿物。大约90%的锂赋存在硅酸盐矿物中,约8.5%的锂赋存在碳酸盐矿物中,孔隙水中的锂含量占比仅约1.5%。碳酸盐矿物中Mg/Li摩尔比值为78~270,是孔隙水中10多倍,而硅酸盐矿物中的Mg/Li摩尔比值稳定在24~29。水-沉积物相互作用促进硅酸盐矿物中锂的释放,咸水环境下释放的锂多于淡水环境下。碳酸盐矿物中,锂和镁主要存在于方解石中。镁离子对锂离子的迁移具有阻碍作用,低温、高盐度下的阻碍作用更强。湖泊沉积物可能是湖水锂的一个重要来源。As a strategic mineral in China,lithium(Li)ore mainly exists in the salt lakes of Tibet Plateau.The enrichment and migration of Li are related to the efficient extraction and estimation of Li resources.The concentration and migration of lithium in lake system are related to the efficient extraction of lithium ore and the estimation of future lithium reserves.Taking the borehole sediments of Guozha Co,a salt water lake in Xizang Province as an example,combined with the changes of Mg content and AMS 14 C age,the changes of lithium content in pore water,carbonate minerals and silicate minerals were systematically analyzed,and discussed the influence of mineral,Mg,environmental changes and early diagenesis on the migration and enrichment of Li.Most of the Li and Mg are found in silicate minerals in the lake sediments,and the high correlations between Li and Mg indicates that they exist in the same silicate minerals,such as clay minerals.About 90%of Li occurs in silicate minerals,about 8.5%in carbonate minerals,and about 1.5%in pore water.The Mg/Li molar ratios in carbonate minerals range from 78 to 270,which is more than 10 times those of pore water,while those in silicate minerals are stable between 24 and 29.Water-sediment interactions promote the release of Li from silicate minerals,more Li released in salt water than in freshwater environments.In carbonate minerals,Li and Mg are mainly found in calcite.Mg ions impede the migration of Li+,and stronger at low temperature and/or high salinity.Lake sediments may be an important source of Li+in lake water.

关 键 词：锂矿 湖泊沉积物 矿物 环境变化 元素 

分 类 号：O657.31[理学—分析化学] TH744.11[理学—化学]