扎麻山南坡花岗岩微量元素地球化学及铜多金属矿化研究

Study on the trace element geochemistry and copper polymetal mineralization in Zhamashannanpo granite

文中对青海都兰扎麻山南坡花岗岩微量元素地球化学研究表明,扎麻山南坡花岗岩稀土总量较高,轻稀土相对重稀土富集,具有δEu负异常,稀土元素配分模式呈右倾的"V"字型,明显富集Rb、K、Th等大离子亲石元素,相对亏损Ba、Sr、Nb、Eu等元素,可能为后碰撞阶段壳-幔岩浆混合作用的结果。通过微量元素构造环境判别表明,都兰扎麻山南坡花岗岩形成于碰撞期后由压性转为张性的构造环境。该区铜多金属矿成矿元素含量高,在类型上属于热水沉积-热液改造型Cu、Ag、Pb、Zn矿床。

The trace element geochemistry in Zhamashannanpo granite in Qinghai Dulan is studied in this paper and the resulf shows that the granifes REE is higher;the LREE is enricher than HREE with Eu negative anomaly;the REE model is right-slope＂V＂shape;enrichment of Rb,K,Th and other large-ion lithophile elements and loss of Ba,Sr,Nb elements and this may be formed by the crust and manfle magma mixing action during the post-collisional period.Based on the discrimination of the trace element tectonic environment,the granife in zhamashannanpo was formed in the post-collisional period from the compressive to the teusile surroundings,The conteut of the copper polymetal minevalization elements is high and in the type,belongs to the hydrothermal sedimentation and the transformation type of Cu,Ag,Pb and Zu deposit.