摘要
采用世界上最先进的ＳＨＲＩＭＰ锆石Ｕ－Ｐｂ测年技术，对招掖地区郭家岭型花岗岩及成矿后花岗斑岩脉进行了年代学研究，精确地测定了郭家岭型花岗岩的年龄为１３０－１２６Ｍａ，成矿后花岗斑岩脉的年龄为１２０±２Ｍａ，金矿化被限定在１２６－１２０Ｍａ之间。结合岩体年龄和与金矿化密切的空间关系及地球化学上的亲缘关系，认为郭家岭型花岗岩属造山晚期花岗岩，金矿化主要与郭家岭型花岗岩有关。该花岗岩异常高的Ｂａ、Ｓｒ含量可作为太古宙绿岩地体环境下判别与金矿化有关花岗岩的地球化学标志。
Zhaoye district, Jiaodong is part of Jiaobei terrane bounded by NNE-trending Tan-Lu fault zone to east. The basement rocks are greenstones of New Archean Jiaodong formation. The region has been intruded by a range of plutonic intrusions which are spatially related to gold mineralization. Guojialing suite intrusions, post mineralization dyke in Zhaoye district have been studied on chronology by using the most advanced SHRIMP U-Pb zircon dating technique in the world. Accurately determined Guijialing suite granite age at 130-126 Ma, the age of post mineralization dyke is 120 Ma. Therefore,gold mineralization in the region took place between 126 Ma and 120 Ma. Combine with magmatic body age and rock geochemistry.It is considered that Guijialing suite granite belongs to postorogenic granite This suite has relatively high Al 2O 3, MgO, Fe 2O 3, FeO, CaO, Na 2O, but lower SiO 2, K 2O contents and very high Ba, Sr compared with the earlier granitoid suites. These characteristics may distinguish goldbearing granite geochemistry marks in Archean green stone terrain.
出处
《地质科学》
CAS
CSCD
北大核心
1998年第3期318-328,共11页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
中国和西澳经济技术研究基金
