摘要
刘村岩体岩石类型主要为中细粒似斑状二长花岗岩,部分为粗中粒二长花岗岩,两者呈渐变过渡关系。具准铝质-弱过铝质的高钾钙碱性系列岩石特征。其LREE/HREE、La N/Yb N值较大,显示其轻重稀土分馏明显,富集轻稀土、亏损重稀土。岩石总体具有大离子亲石元素(LILE)Rb、Th富集,Sr、Ba亏损,高场强元素(HFSE)U、La、Ce、Nd、Hf、Zr富集,Nb、Ta、Ti亏损,岩体整体亏损HFSE,富集LILE。通过LA-ICP-MS锆石U-Pb定年,获得刘村岩体206Pb/238U年龄为123.2±2.2 Ma,属早白垩世岩浆活动产物,代表刘村岩体的成岩年龄。刘村岩体富集—强富集的元素有W、Mo、Zn、As、Sb、Hg、Cu、Au等,表明该岩体是铜及多金属富集成矿的有利地段。
The Liucun rockmass is dominated by medium- and free-grained porphyroblastic monzogranites with less coarse- and medium-grained monzogranites, the two being in transitional relationship, typical of quasi-a luminous to weakly peraluminous high-K talc-alkaline series. The LREE/HREE and LaN/YbN are higher, indicating remarkable fractionation of LREE and HREE, with enrichment of LREE and depletion of HREE. Generally, the rocks are rich in LILEs of Rh and Th and poor in Sr and Ba, rich in HFSEs of U, La, Ce, Nd, Hf and Zr, and poor in Nb, Ta and Ti. As a whole, the rocks are low in HFSE and high in LILE. LA-ICP-MS zircon U-Pb dating gave a 206Pb/238U age of 123.2±2.2 Ma for the Liucun rockmass, belonging to product of early Cretaceous magmatism, representing the time of diagenesis of the Liucun rockmass, which is high and very high in elements of W, Mo, Zn, As, Sb, Hg, Cu and Au, suggesting that the rockmass is favorable to mineralization of copper and polymetals.
出处
《安徽地质》
2017年第3期161-167,共7页
Geology of Anhui
基金
安徽省公益性地质项目誓节渡等四幅1:5万区域矿产地质调查(2011-g-17)资助
