广西武宣盘龙铅锌矿喷流沉积成矿作用:稀土元素和硫同位素证据  

SEDEX Origin of the Panlong Lead-Zinc Deposit,Wuxuan,Guangxi:REE and S Isotope Evidences

作　　者：薛静[1] 戴塔根[1] 付松武[1] 马国秋 黄伟盟 

机构地区：[1]中南大学地球科学与信息物理学院,湖南长沙410083 [2]广西武宣县盘龙铅锌矿,广西武宣545900

出　　处：《大地构造与成矿学》2011年第3期394-403,共10页Geotectonica et Metallogenia

基　　金："广西壮族自治区武宣县盘龙铅锌矿成矿控矿规律与找矿预测研究"项目资助

摘　　要：盘龙铅锌矿是桂中地区典型的大型铅锌矿床。文章系统地总结了该矿床的地质特征,初步提出了矿床的成因类型。研究结果表明:盘龙铅锌矿位于大瑶山西侧铅锌多金属成矿带南段,矿体顺层发育于下泥盆统上伦组白云岩中。矿床中发育层状、条纹-条带状构造、同沉积角砾岩和层间揉皱等,沉积特征明显,矿化与白云岩化、重晶石化及硅质岩关系比较密切。稀土元素研究表明成矿作用与热水沉积作用有关,硫同位素分析结果暗示成矿物质来源于深源岩浆和泥盆纪海水的共同作用。矿床地质特征和地球化学特征显著区别于MVT型铅锌矿床,应属于海底喷流-沉积型铅锌矿。The Panlong lead-zinc deposit in central Guangxi is a giant lead-zinc deposit.Previous studies and field evidence shows that this deposit hostes in dolomite of the Lower Devonian Shanglun Formation in the south of the western side of the Dayaoshan lead-zinc polymetallic metallogenic belt and ore beds confined to barite-bearing,dolomite and siliceous rocks.The ore structures include stratiform,laminated,banded,sedimentary brecciated and interbedded corrugation,which exhibit sedimentary origin.REE concentrations of the ores are characterized by variable total REE concentrations（4.55～221.75μg/g）,slightly LREE enrichment（LaN/YbN=3.16～29.60,LREE/HREE=7.16～23.34）,slightly depleted in Ce-annomalies and pronounced postive Eu-annomalies,indicating that the lead-zinc mineralization was probably related to hydrothermal sedimentation.Most sulfide δ34S values range from-7.1‰ to 7.7‰,except two pyrites with δ34S values of-21‰ and-20.6‰,respectively;while the δ34S values of barites range from 17.3‰～26.6‰,which suggest that the sulfur in ores was mainly derived from mantle and sea water.The geological and geochemical characteristics of the deposit are obviously different from those of the MVT deposits,instead,evidence shows that the deposit is of SEDEX type.

关 键 词：喷流-沉积 铅锌矿 大瑶山西侧铅锌多金属成矿带 武宣 广西 

分 类 号：P611[天文地球—矿床学]