滇西兰坪盆地金顶铅锌矿区石膏的地球化学特征及其指示意义  

Geochemical Characteristics of Gypsum and Its Geological Significance in Jinding Mining Area of Lanping Basin,Western Yunnan

作　　者：朱志军[1,2] 郭福生[1,2] ZHU Zhi-jun;GUO Fu-sheng(State Key Laboratory Breeding Base of Nuclear Resources and Environment,East China University of Technology,Nanchang,JX 330013,China;School of Geosciences,East China University of Technology,Nanchang,JX 330013,China)

机构地区：[1]东华理工大学省部共建核资源与环境国家重点实验室培育基地,江西南昌330013 [2]东华理工大学地球科学学院,江西南昌330013

出　　处：《东华理工大学学报（自然科学版）》2018年第3期226-235,共10页Journal of East China University of Technology(Natural Science)

基　　金：国家自然科学基金项目(41362008;U0933605);江西省教育厅科技项目(GJJ14475)

摘　　要：为了解兰坪盆地金顶矿区石膏与金属成矿的关系,对矿区石膏开展了稀土、微量元素、锶和硫同位素地球化学特征研究,结果表明,矿区石膏中锶同位素(87Sr/86Sr=0. 707695～0. 707988,平均为0. 707817)与晚三叠世三合洞组灰岩中锶同位素(87Sr/86Sr=0. 707795～0. 708313,平均为0. 707984)相近。石膏中硫同位素δ34SV-CDT为+12. 6‰～+17. 99‰,平均为+15. 05‰,与三叠纪末期古大洋硫酸盐δ34S值(+15‰)相近,结合稀土元素地球化学特征参数及配分模式对比分析得出矿区厚层-块状石膏为晚三叠世三合洞组蒸发沉积型石膏。通过对比金顶矿区石膏与不同矿化阶段单矿物(石英、方铅矿和黄铁矿)流体包裹体的稀土元素地球化学特征参数及微量元素地球化学特征分析,揭示了晚三叠世三合洞组石膏与金顶金属硫化物成矿关系密切。In order to understand the relationship between gypsum and metallogenic in Jinding mining area of Lanping basin,the rare earth,trace elements,strontium and sulfur isotopes of gypsum have been studiel.The results show that strontium isotope of gypsum(87 Sr/86 Sr=0.707 695~0.707 988,averaging 0.707 817)is close to strontium isotope in the limestone samples of Sanhedong formation in Late Triassic(87 Sr/86 Sr=0.707 795~0.708 313,averaging 0.707984).Sulfur isotopeδ34 S V-CDT of gypsum is mainly concentrated in 12.6%~17.99%,averaging+15.05‰,close toδ34 S(+15‰)of Late Triassic Paleo oceanic sulfate,combined with the geochemical characteristics of rare earth elements and the distribution patterns of REE,the results show that the thick-massive layer of gypsum is evaporation and deposition plaster of Sanhedong formation in Late Triassic.The REE geochemistry parameters of gypsum in Jinding mining area compare with single mineral fluid inclusion of different mineralization stages,and geochemical analysis of trace elements,the results show that the relationship between gypsum of Sanhedong formation in Late Triassic and metal sulfide mineralization is closely.

关 键 词：金顶矿区 石膏 地球化学特征 兰坪盆地 

分 类 号：P618.4[天文地球—矿床学]