乌什北山地区铝土矿层地球化学特征及富锂性讨论  

Geochemical Characteristics and Lithium Enrichment of Bauxite in Beishan Area,Wushi County

作　　者：魏翔 张博文 杨习俊 王琦玮 苏春媚 WEI Xiang;ZHANG Bowen;YANG Xijun;WANG Qiwei;SU Chunmei(School of Geology and Mining Engineering,Xinjiang University,Urumqi Xinjiang 830017,China;Xinjiang Key Laboratory of Continental Dynamics and Metallogenic Prognosis of Central Asian Orogenic Belt,Xinjiang University,Urumqi Xinjiang 830017,China;Xinjiang Uygur Autonomous Region Bureau of Geology and Mineral Exploration and Development,8th Geological Brigade,Aksu Xinjiang 842008,China)

机构地区：[1]新疆大学地质与矿业工程学院,新疆乌鲁木齐830017 [2]新疆大学新疆中亚造山带大陆动力学与成矿预测自治区重点实验室,新疆乌鲁木齐830017 [3]新疆维吾尔自治区地质矿产勘查开发局第八地质大队,新疆阿克苏842008

出　　处：《新疆大学学报（自然科学版中英文）》2024年第6期702-711,共10页Journal of Xinjiang University(Natural Science Edition in Chinese and English)

基　　金：新疆维吾尔自治区自然科学基金“东准噶尔卡拉麦里晚古生代A型花岗岩对岩石圈拆沉响应”(2021D01C042).

摘　　要：乌什县北山地区位于中国新疆南天山塔里木板块西北缘石炭纪被动大陆边缘,其含锂铝土矿层主要赋存于阿依里河组碳酸盐岩古风化侵蚀面.通过岩石地球化学研究表明,该地区铝土矿层锂元素存在富集性,远高于黏土型锂矿边界品位,其中铝土矿样品中Li含量为2.04×10^(-6)~1005.54×10^(-6)、铝土岩样品为2.94×10^(-6)~11.70×10^(-6)、黏土岩样品为7.88×10^(-6)~2039.07×10^(-6),均值为342.25×10^(-6),且Li与Al_(2)O_(3)、SiO_(2)、Fe_(2)O_(3)、REE呈正相关,与A/S值呈负相关,表明Li的富集与铝土矿形成密切相关.总体来看,北山地区铝土矿层A/S值、La/Y值分别为0.8~3.8、0.8~1.0时,Li富集程度最高,表明其在古风化作用pH值近中性、程度中等的黏土化阶段最利于富集成矿,且大多数可能赋存在以高岭石为主的黏土矿物中.The Beishan area of Wushi County is located in the Carboniferous passive continental margin of the northwestern margin of the Tarim plate in the South Tianshan Mountains,Xinjiang of China.The lithium bauxite deposits mainly occur in the paleo-weathering erosion surface of the Ayilihe Formation carbonate rocks.The study of rock geochemistry shows that there is enrichment of lithium in the bauxite deposits in this area,which is much higher than the boundary grade of lithium.The bauxite sample is 2.04×10^(-6)~1005.54×10^(-6),the bauxite stone sample is 2.94×10^(-6)~11.70×10^(-6),and the clay rock sample is 7.88×10^(-6)~2039.07×10^(-6),with an average of 342.25×10^(-6).Moreover,Li is positively correlated with Al_(2)O_(3),SiO_(2),Fe_(2)O_(3) and REE,and negatively correlated with A/S value,indicating that Li enrichment is closely related to bauxite formation process.In general,when the A/S value and La/Y value of bauxite in Beishan area are 0.8~3.8 and 0.8~1.0,respectively,the enrichment degree of Li is the highest,which indicates that the pH value of bauxite is near neutral and the degree of claying is moderate,which is most conducive to mineralization,and most of them may occur in clay minerals dominated by kaolinite.

关 键 词：乌什北山 铝土矿层 地球化学 富锂机制 

分 类 号：P618.71[天文地球—矿床学]