作　　者： ; ; ; ; ; ; ; ; ; ;

机构地区： 成都理工大学

出　　处： 《地质与勘探》 2013年第4期676-688,共13页

摘　　要： 尕尔穷-嘎拉勒矿集区位于西藏班公湖-怒江成矿带西段,是该带上近年来取得重大勘查突破的矽卡岩(斑岩)型铜金矿集区,区内现已发现有尕尔穷及嘎拉勒两个矽卡岩型铜金矿床。区内侵入岩主要有GL(嘎拉勒)花岗闪长岩、GL花岗斑岩、GL闪长岩、GE(尕尔穷)花岗斑岩、GE石英闪长岩等燕山晚期中酸性侵入岩。地球化学特征显示,区内侵入岩SiO2含量在53.68%～80.78%之间,平均值为65.66%,Al2O3含量在8.51%～16.91%之间,A/CNK(铝饱和指数)在0.54～1.11之间,表明区内侵入岩为准铝质-弱过铝质钙碱性-高钾钙碱性岩石系列;微量元素及稀土元素地球化学特征显示,区内侵入岩相对富集大离子亲石元素Rb、Sr、Th,而亏损Ta、Nb、Hf、Zr、Yb、Ti等高场强元素,各岩石类型均具Nb、Ta、Ti负异常,其中GE花岗斑岩具有非常明显的亏损Sr和Ti的特征。岩石成因类型判别表明GE花岗斑岩为S型花岗岩,而其它岩类为I型花岗岩,结合构造环境的判别,指示矿集区侵入岩形成于班公湖-怒江特提斯洋闭合后碰撞隆升阶段。 The Ga＇ erqiong-Galale ore-concentration area,located in the western segment of the Bangong-Nujiang metallogenic belt,is a skarn （por- phyry） copper-gold ore concentration area where significant exploration breakthrough has been achieved in recent years. The Gaerqiong and Galale coppergold deposits have been discovered in this ore concentration area. The types of the intrusive rocks include GL （Galale） granodiorite, GL granite porphyry, GL diorite,GE （Gaerqiong） granite porphyry and GE quartz diorite. Geochemical characteristics indicate that the co （ SiO2 ） ： 53.68% - 80.78% , co （ A1203 ） ： 8.51% - 16.91% ,A/CNK： 0.54 - 1.11 ,implying that the intrusive rocks are of metaluminous-weakly metaluminous calc-alkaline-K calc-al- kaline stocks. Geochemical characteristics of trace elements and rare earth elements indicate that the intrusive rocks are enriched in Rb, Sr and Th, and de- pleted in Ta, Nb, Hf, Zr, Yb and Ti. All the intrusive rocks have negative anomalies of Nb,Ta and Ti, and the GE granite porphyry deficits Sr and Ti especially. Distinguishing of the petrogenesis type indicates that GE granite is granite of S-type,others are granite of I-type. Mentification of tectonic environments suggests that the intrusive rocks in ore concentration area were formed in the stage of the colfision uplift after the closing of the Bangong-Nujiang Tethys ocean.

关 键 词： 尕尔穷 嘎拉勒矿集区 地球化学 班公湖 怒江带 西藏

领　　域： [天文地球] [天文地球]