摘要
安徽茂林岩体为中国东部中生代皖南构造-岩浆带中的一个浅层侵入岩体,是檀树岭钼矿和湛岭钼矿的成矿母岩。该岩体的主要岩性为花岗闪长岩、花岗斑岩、斑状花岗闪长岩、二长花岗岩等。对茂林花岗闪长岩体进行LA-ICP-MS锆石U-Pb测年,结果显示锆石Th/U值为0.38~0.66,为典型的岩浆成因锆石。花岗闪长岩206Pb/238U年龄加权平均值为140.8±0.8Ma(n=19,MSWD=2.3),结合锆石自形、岩浆环带发育等特点,该年龄为茂林花岗闪长岩的成岩年龄,显示岩体形成于早白垩世。锆石Hf同位素分析结果显示,茂林花岗闪长岩锆石振荡岩浆环带具负εH( f t)值(-9.7^-6.2),揭示花岗闪长岩主要形成于下地壳的熔融。
The Maolin pluton is a superficial intrusive body distributed in Maolin Town of Jingxian County. It is an important part of southern Anhui Mesozoic tectonic-magmatic belt in East China, and the granodiorites are parent rocks of the Tanshulin Mo deposit and Zhanlin Mo deposit in southern Anhui. The main lithologies are granodiorites, granite- porphyry, porphyry granites and monzogranite. The LA- ICP- MS zircon U- Pb data show that these rock bodies were formed at 140.8 ± 0.8Ma, the zircon has euhedral and magma ring characteristics, and the dating shows that the diagenetic age of Maolin granodiorite is Early Cretaceous. Zircon Hf isotopic data indicate that the zircon zones in the granodiorite samples are heterogeneous in εHf (t) values (- 9.7^- 6.2), probably indicating the mixed crust materials during the formation of the magma, with old crustal rocks being the main source.
作者
陈瑞莉
潘家永
伍俊杰
陈芳
CHEN Ruili;PAN Jiayong;WU Junjie;CHEN Fang(East China University of Technology,Nanchang 330013,Jiangxi,China;Geological Survey of Anhui Province,Hefei 230015,Anhui,China)
出处
《地质通报》
CAS
CSCD
北大核心
2019年第7期1219-1227,共9页
Geological Bulletin of China
基金
安徽省国土资源厅项目《安徽省岩浆岩数据集成及成矿专属性评价》(编号:2016-g-1-3)
