鲁西地区稀土矿床成矿系列划分与找矿新突破  

New Breakthroughs in Metallogenic Series Division and Prospecting of Rare Earth Deposits in Western Shandong Province

作　　者：兰君 张鹏 孙莉[2] 邢楠 李得建 杨云涛 李衣鑫 肖克炎[2] 徐洪岩 王健 LAN Jun;ZHANG Peng;SUN Li;XING Nan;LI De-jian;YANG Yun-tao;LI Yi-xin;XIAO Ke-yan;XU Hong-yan;WANG Jian(The Fifth Geological Brigade of Shandong Provincial Bureau of Geology and Mineral Resources,Academician Workstation of Shandong Province,Taian,Shandong 271000;MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037;Guangxi Key Laboratory of Hidden Metal Mineral Exploration,Guilin,Guangxi 541004;Shandong Weishanhu Rare Earth Co.,Ltd.,Jining,Shandong 277600)

机构地区：[1]山东省地质矿产勘查开发局第五地质大队,山东省院士工作站,山东泰安271000 [2]中国地质科学院矿产资源研究所,自然资源部成矿作用与资源评价重点实验室,北京100037 [3]广西隐伏金属矿产勘查重点实验室,广西桂林541004 [4]山东微山湖稀土有限公司,山东济宁277600

出　　处：《地球学报》2023年第5期933-942,共10页Acta Geoscientica Sinica

基　　金：山东省自然资源厅“山东省微山县郗山地区稀土矿深部及外围调查评价”(编号:鲁勘字(2018)30号);山东地矿局基金项目“微山-枣庄地区稀土矿成矿作用及找矿方向研究”(编号:KC202104)和“济宁市郗山地区稀土矿成矿机理研究”(编号:KY202207)联合资助

摘　　要：鲁西地区是我国重要的稀土基地,目前已发现并评价了4个稀土矿(床)点:微山县郗山特大型稀土矿、枣庄薛城关帝庙稀土矿点、兰陵龙宝山中型稀土矿、淄博—莱芜地区稀土矿点。根据近年来的研究成果,厘定出与燕山晚期岩浆有关的与构造-岩浆作用有关的稀土矿床成矿系列。根据稀土矿形成依存的构造-岩浆条件,该矿床系列形成于整个中生代,贯穿于燕山晚期,初步分为一个稀土矿成矿亚系列:与构造-岩浆及岩浆热液有关的成矿亚系列,成矿年龄110~(134.9±1.8)Ma。通过选取郗山稀土矿和胡家庄稀土矿进行同位素研究,郗山稀土矿方解石及矿体中δ^(18)O_(V-SMOW)为8.2‰~9.1‰,δ^(13)C_(V-PDB)为–7.5‰~–7.1‰,成矿物质与碱性岩浆最初可能来源于上地幔;胡家庄含稀土碳酸岩C同位素显示有幔源特征,O同位素落入海相碳酸岩和幔源碳酸岩之间,显示有海相碳酸岩特征,因此推测,方解石矿物经历过后期改造成为次生矿物,为成矿热液与围岩进行水岩反应混合后的结果,二者成矿物质来源具有幔源特征,成矿物质来源相似。根据成矿系列理论,在郗山稀土矿开展系统找矿工作,以寻找中生代郗山碱性杂岩体为找矿目标,提交特大型稀土矿床1处,取得了重大找矿突破,证实了鲁西地区具有较好的找矿前景。Western Shandong region is an important rare earth base in China.Four rare earth mines(deposits)have been found and evaluated;namely,Xishan Extra Large Rare Earth Mine in Weishan County,the Zaozhuang Xuecheng Guandi Temple rare earth mine,the medium Lanling Longbaoshan rare earth mine,and the Zibo–Laiwu rare earth mine.The metallogenic series of rare earth deposits related to Late Yanshanian tectonic magmatism are determined based on recent research.According to the tectonic and magmatic conditions on which the formation of rare earth deposits depends,the deposit series was formed in the Mesozoic era and continued through the Late Yanshanian period.It is preliminarily divided into a rare earth ore forming subseries:a metallogenic sub series related to tectonic magma and magmatic hydrothermal,with a metallogenic age of(110±4.2)-(134.9±1.8)Ma.Through an isotope study of Xishan rare earth ore and Hujiazhuang rare earth ore,^(18)O_(V-SMOW) in the calcite and ore body of Xishan rare earth ore was determined to be 8.2‰-9.1‰,δ^(13)C_(V-PD)B is-7.5‰--7.1‰,and the ore-forming materials and alkaline magma may originate from the upper mantle.The C isotope of Hujiazhuang rare earth bearing carbonatite shows mantle source characteristics,and the O isotope falls between the marine carbonatite and the mantle carbonatite,showing the characteristics of marine carbonatite.Therefore,it is speculated that the calcite mineral has undergone a late transformation into a secondary mineral,as a result of the water rock reaction of the ore-forming hydrothermal solution and the wall rock.The source of the ore-forming materials of the two minerals has mantle source characteristics,and the source of the ore-forming materials is similar.In accordance with the metallogenic series theory,systematic prospecting work was conducted in the Xishan rare earth ore deposit with the goal of finding the Mesozoic Chishan alkaline complex.One super-large rare earth deposit was discovered,confirming that the western Shandong region has suitable

关 键 词：稀土 成矿系列 成矿物质来源 新突破 

分 类 号：P618.7[天文地球—矿床学]