鲁西龙宝山地区隐爆角砾岩特征及稀土成矿意义  

Characteristics of Crypto-explosive Breccia and Significance of Rare Earth Mineralization in Longbaoshan Area in Western Shandong Province

作　　者：高文白 陈怀鑫 徐然[1] 姜腾飞 尚振 马钊 GAO Wenbai;CHEN Huaixin;XU Ran;JIANG Tengfei;SHANG Zhen;MA Zhao(Lu'nan Geo-engineering Exploration Institute(No.2 Geological Brigade of Shandong Provincial Bureau of Geology and Mineral Resources),Shandong Yanzhou 272100,China;Shandong Engineering Research Center for Exploration and Comprehensive Utilization of Three Rare Mineral Resources,Shandong Yanzhou 272100,China)

机构地区：[1]山东省鲁南地质工程勘察院(山东省地质矿产勘查开发局第二地质大队),山东兖州272100 [2]三稀矿产勘查与综合利用山东省工程研究中心,山东兖州272100

出　　处：《山东国土资源》2024年第11期1-11,共11页Shandong Land and Resources

基　　金：山东省2022年自然资源科技项目“兰陵县龙宝山地区隐爆角砾岩与稀土矿成因分析”(LNY202207)。

摘　　要：兰陵县龙宝山稀土矿是鲁西重要的稀土矿床,其分布受热液流体控制明显,而隐爆角砾岩作为良好的流体通道和容矿空间,为稀土矿勘探的有利目标。通过野外勘查、岩相学观察、扫描电镜以及能谱仪分析,研究隐爆角砾岩筒的结构及其对应的热液蚀变矿化情况,来探讨龙宝山地区隐爆角砾岩的稀土分布规律,结果表明:龙宝山隐爆角砾岩体从内至外大致分为隐爆角砾岩类、隐爆热液岩浆圆化角砾岩类、隐爆震碎角砾岩类以及隐爆破裂岩类多种类型;隐爆角砾岩类、隐爆热液岩浆圆化角砾岩类、隐爆震碎角砾岩类岩石,其分别对应着黄铁绢英岩化、钾长石化绢英岩化以及硅化碳酸盐化;钾化热液富含稀土络合阴离子有助于其迁移,而且黄铁绢英岩化与钾长石化可造成pH和温度的降低等有利于REE沉淀的环境,发生此类蚀变作用的隐爆角砾岩类与隐爆热液浆液圆化角砾岩类是稀土富集的有利场所。Longbaoshan rare earth deposit in Lanling county is an important rare earth deposit in western Shandong.Its distribution is significantly controlled by hydrothermal fluids.As a good fluid channel and ore bearing space,crypto-explosive breccia is a favorable target for rare earth exploration.Through field exploration,petrographic observation,scanning electron microscopy,and energy spectrum analysis,the structure of crypto-explosive breccia tube and its corresponding hydrothermal alteration,and rare earth distribution pattern of crypto-explosive breccia in Longbaoshan area have been studied.It is showed that crypto-explosive breccia ore bodies in Longbaoshan can be divided into crypto-explosive breccia,crypto-explosive hydrothermal—Magma rounded breccia,crypto-explosive shattered breccia and crypto-explosive fractured rock from inside to outside.The main types of rocks affected by mineralized fluids include cryptoexplosive breccia,crypto-explosive shattered breccia,crypto-explosive hydrothermal rounded breccia,which correspond to pyrite sericitization,silicification carbonation,and potassium feldspar sericitization.Potassium hydrothermal fluids are rich in rare earth complex anions,which facilitate their migration.Moreover,pyrite sericite and potassium feldspar can cause a decrease in pH value and temperature,which is conducive to the precipitation of REE.Cryptoexplosive breccias and cryptoexplosive hydrothermal magma rounded breccias that undergo such alteration are favorable for rare earth enrichment.

关 键 词：稀土 隐爆角砾岩 热液蚀变作用 鲁西龙宝山 

分 类 号：P618.7[天文地球—矿床学]