赣南某离子吸附型稀土矿床浅变质岩的矿化特征
REE Mineralization of Epimetamorphic Rocks from an IonAdsorption Type REE Deposit in Southern Jiangxi Province

近几年在赣南新元古代浅变质岩风化壳中发现了离子吸附型稀土矿床，对矿区及南岭科学深钻中的浅变质岩样品进行了岩石、矿物及地球化学特征研究.矿区内主要出露神山组和库里组(南华系)，前者以千枚岩为主,含少量片岩，后者以厚层变质沉凝灰岩和中厚层变质砂岩为主；南岭科学深钻1 165~1 170.77 m库里组(青白口系)以变质沉凝灰岩为主夹薄层凝灰质板岩.浅变质岩类中新生变质矿物有绢云母、绿泥石、磁铁矿、堇青石、白云母、黑云母等，稀土矿物有新奇钙铈矿、独居石、磷钇矿、水独居石等；稀土含量为162×10-6~723×10-6，富集轻稀土.新奇钙铈矿是矿体中离子相稀土的主要来源；赣南青白口纪-南华纪中厚层变质沉凝灰岩和变质凝灰岩风化壳具有较好的稀土成矿前景.
An ion-adsorption type REE deposit occurs in regolith of epimetamorphic rocks formed in Neo-Proterozoic, and has been discovered in South Jiangxi Province in recent years. Petrological and geochemical characteristics of the rocks from the REE deposit and Nanling scientific drilling were studied in this paper. Shenshan Formation and Kuli Formation are widely exposed in the deposit, and the former consists mainly of phyllite and minor schist whereas the latter consists of thick-layer metatuffite, metamorphic tuff, and medium-thick-layer metasandstone. Kuli Formation is composed of metamorphic tuff with thin layer tuffaceous slate that intersected by Nanling scientific drilling from 1 165 m to 1 170.77 m. The epimetamorphic rocks with neo formation of sericite, chlorite, magnetite, cordierite, muscovite, biotite, etc. contain REE minerals such as synchysite-(Ce), monazite, xenotime and rhabdophane-(La) etc. They are enriched in REEs (162×10-6 to 723×10-6) with high LREE/HREE ratios (LREE/HREE=2-7).We suggest that Ionadsorbed REEs in the regolithic zone of the epimetamorphic rocks are mainly sourced from REE-fluorocarbonate. Regolith of metamorphic tuff and metatuffite formed in Cryogenian in South Jiangxi Province should be included during REE-bearing properties evaluation and prospecting