摘要
建水县黄草坝岩体岩石地球化学分析表明,岩体∑REE488.87×10^(-6)~943.76×10^(-6),LREE/HREE12.43~29.75,指示轻稀土富集,重稀土亏损,具不明显负铕异常(δEu=0.83~0.87),负铈异常(δCe=0.89~0.90),在稀土元素球粒陨石标准化配分模式图上,稀土分馏明显,暗示岩浆源区可能来自壳幔混溶。微量元素原始地幔标准化蛛网图中,具明显的锯齿状分配形式,为典型富钾玄武岩特征,岩石总体富集放射性元素(Th、U)、大离子亲石元素(LREE、Zr、Sm),明显亏损Ta、P、Ti等元素。锆石LA-ICP-MS测年结果80.02±0.7Ma,与个旧花岗岩基中碱性侵入岩为同一构造热事件的产物。
The rock geochemical analysis of Huangcaoba rockbody in Jianshui shows rockbodyΣREE488.87×10^(-6)-943.76×10^(-6),LREE/HREE 12.43-29.75,meaning LREE richness,HREE deficit,not clear negative Eu anomaly(δEu 0.83-0.87),negative Ce anomaly(δCe 0.89-0.90),on chondrite-normallized REE Pattern,REE fractional distillation clear,meaning magmatic source area maybe crust-mantle mix-derived.On the trace element original mantle normallized cobweb diagram,it shows the clear zigzag distribution pattern,which is the typical k-rich basalt feature.The rock is generally rich in radioactive element(Th,U),big ion lithophile element(LREE,Zr,Sm),clear deficit Ta,P,Ti,etc,zircon LA-ICP-MS,U-Pb dating 80.02±0.7Ma,which is formed in the same tectonic heat event with the alkaline intrusion of Gejiu granite batholite.
作者
张星培
顾雄
杨钦淞
陈少伟
ZHANG Xing-pei;GU Xiong;YANG Qin-song;CHEN Shao-wei(Yunnan Au Mining Group Company(Ltd),Kunming 650299;Yunnan Exploration-Design Institute Company(Ltd)of Geological Engineering,Kunming 650200)
出处
《云南地质》
2022年第3期297-303,共7页
Yunnan Geology
