西藏冈底斯成矿带东段花岗岩类的区域岩石学及找矿前景

对冈底斯东段古新世-始新世花岗岩类进行了岩相学、地球化学、大地构造环境、成矿专属性研究，表明花岗岩类呈现准铝-过铝质的特征，属于高钾钙碱性岩石，轻稀土元素富集，重稀土元素亏损，负Eu、Ce异常不明显，富集大离子亲石元素Rb、Sr、Th等，高场强元素Nb、Hf则表现为亏损，大离子亲石元素Rb、Th的富，说明源区的部分熔融程度较高.古新世花岗岩类为变质泥岩、砂岩部分熔融的产物，始新世花岗岩类为角闪岩部分熔融的产物.冈底斯东段古新世-始新世花岗岩类形成于印度-欧亚板块陆陆碰撞阶段，成矿专属性表现为Cu、Mo等.

REGIONAL PETROLOGY AND METALLOGENIC PROSPECT OF THE GRANITOID IN THE EAST OF GANDISE METALLOGENIC BELT, TIBET

Study on the petrology, geochemistry, tectonic environment and metallogenic specialization of the Paleocene- Eocene granitoid in the east of the Gandise metallogenic belt shows that the granitoid expresses metaluminousperaluminous characteristics, belonging to high-K talc-alkaline rocks, with enriched LREE and depleted HREE. The rocks are also characterized by slightly negative Eu and Ce anomalies, enriched LILE （especially Rb, Sr and Th） and depleted HFSE （Nb and Hf）. The enrichment of Rb and Th indicates a high degree of partial melting in the source. The Paleoeene granitoid is the result of partial melting of sandstone and metapelites. The Eocene granitoid is the product of partial melting of amphibolite. The Paleocene-Eocene granitoid in eastern Gandise is formed in during the collision between Indian palate and Euro-Asian plate, with the metallogenic specialization of Cu, Mo, etc.