摘要
王仙岭花岗岩侵位于印支期。过去一直认为荷花坪锡铅锌矿为印支期矿床,与王仙岭岩体有关。经多年的野外考察和钻孔资料研究发现,荷花坪地区存在隐伏花岗岩体,其岩性不同于王仙岭花岗岩。本文选取钻孔中粗粒黑云母花岗岩,利用La-MC-ICP-MS法对其进行锆石年代学研究,获得U-Pb年龄为(157.1±0.8)Ma,显示其为燕山早期。荷花坪花岗岩A/CNK比值为1.02,REE总量为357×10-6,LREE/HREE比值为2.83,Zr+Nb+Ce+Y含量为398×10-6,与A型花岗岩特征一致,明显不同于王仙岭S型花岗岩。这些地球化学特征与南岭地区含锡花岗岩非常类似。南岭地区钨锡成矿大爆发发生在燕山早期,荷花坪锡铅锌矿可能与此燕山期隐伏岩体有关。
The Wangxianling granite was emplaced at the Indosinian（Triassic） period. The previous research considered that the Hehuaping Sn-Pb-Zn deposit was an Indosinian deposit related to the Wangxianling pluton. Based on many years of investigation in the field and study of rocks from drilling holes,a buried pluton with lithological characteristics different from the Wangxianling granite was discovered in the Hehuaping district. A zircon U-Pb age of（157.1±0.8） Ma for the coarse-grained biotite granite from drilling hole was obtained by La-MC-ICP-MS,which suggests an early Yanshanian（Jurassic） emplacement. This granite is characterised by A/CNK value of 1.02,total REE content of 357×10 -6,LREE/HREE ratio of 2.83 and Zr＋Nb＋Ce＋Y content of 398×10 -6,on average. These features are similar to those of A-type granite and markedly different from those of the Wangxianling S-type granite. This Yanshanian granite,named as Hehuaping granite,has an affinity of the tin-bearing granites in the Nanling Range. Therefore,we argue that the Hehuaping Sn-Pb-Zn deposit is related to the Yanshanian buried Hehuaping pluton.
出处
《高校地质学报》
CAS
CSCD
北大核心
2011年第4期513-520,共8页
Geological Journal of China Universities
基金
中国地质调查局调查项目“南岭重要金属矿床成矿机理研究和找矿潜力预测”(1212010632100)
国家自然科学基金(40730423,40873029)
“深部探测技术与实验研究专项”(SinoProbe-03-01-4D)联合资助
