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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 Gaerlian-Galalare ore district is located in the western section of the Bangonghu-Nujiang metallogenic belt in Tibet, and is the area where the skarn (porphyry) type copper-gold deposits have taken major exploration breakthroughs in recent years. Within the area It has been found that there are Gaer Po and Galaller two skarn copper and gold deposits. The main intrusive rocks in the area are GL (Galale) granodiorite, GL granite porphyry, GL diorite, GE (Gaer poor) granite porphyry and GE quartz diorite, Invaded rock. Geochemical characteristics show that the content of SiO2 in intrusive rocks is 53.68% ~ 80.78% with an average of 65.66%, Al2O3 content is 8.51% ~ 16.91%, A / CNK is between 0.54 ~ 1.11 , Indicating that the intrusive rocks in the area are quasi-aluminum-weakly perovskite-high-K calc-alkaline rock series. The trace elements and REE geochemical characteristics show that the intrusive rocks in the area are relatively enriched in large ion lithophile elements Rb, Sr, Th, and loss of high field strength elements such as Ta, Nb, Hf, Zr, Yb and Ti. All rock types have negative Nb, Ta and Ti anomalies. GE granite porphyry has a significant loss of Sr And Ti features. The distinguishing of rock genetic type indicates that the GE granitic porphyry is S-type granite and the other types are I-type granites. According to the discrimination of tectonic environment, the intrusive rocks in the ore-bearing area are indicated to form after the closure of the Tengchong-Nujiang Tethyan Ocean Uplift stage.