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大敖包沟铜镍矿位于塔里木板块东南缘,其发现是近年来该区带找矿的重大突破.已发现岩体具有全岩矿化特征,初步划分3个岩相,由橄榄辉石岩、辉石岩和辉长岩组成,岩石w(Si O2)集中于44.2%～49.1%,具低铝、低钛、低碱、高镁、高铁特征,m/f=1.73～6.10,平均4.05,属于铁质超镁铁质岩.在微量元素原始地幔标准化蛛网图上,岩石具有相对富集大离子亲石元素Rb、Ba、K、Sr、LREE、U、Pb,相对亏损高场强元素Nb、Ta、Zr、Hf,以及较高的w(Zr)/w(Y)(0.83～6.41)、w(Ta)/w(Yb)(0.14～0.19)和较低的w(Zr)/w(Nb)(2.65～31.92)地球化学特征.岩石ΣREE=28.25×10-6～45.87×10-6、(w(La)/w(Yb))N=2.56～10.06、δ(Eu)=0.76～1.06,具有LREE相对富集特征.综合大敖包沟岩体地质特征和区域地质背景,推断大敖包沟岩体可能形成于塔里木板块东南缘一个大陆裂谷环境.
The discovery of the Great Obobuogou Cu-Ni deposit on the southeastern margin of the Tarim plate has been a major breakthrough in ore prospecting in the area in recent years, and it has been found that the rock mass has the characteristics of whole rock mineralization and is divided into three lithofacies: olivine pyroxene, Pyroxenite and gabbros. The Si 2 O concentrations range from 44.2% to 49.1% with the features of low Al, low Ti, low alkali, high Mg and high iron, m / f = 1.73-6.10 with an average of 4.05. Belonging to the iron-bearing ultramafic rocks.On the standard trace map of trace elements primitive mantle, the rocks are relatively rich in large ion lithophile elements Rb, Ba, K, Sr, LREE, U, Pb, relative loss high field strength element Nb , Ta, Zr, Hf and higher w (Zr) / w (Y) (0.83-6.41), w (Ta) / w (Nb) (2.65 ~ 31.92) geochemical characteristics of the rock, ΣREE = 28.25 × 10-6 ~ 45.87 × 10-6, (w w / La) / w ~ 1.06 with LREE relative enrichment characteristics.According to the geologic characteristics and regional geological background of the Dadougou rock mass, it is inferred that the Dadougou granite may be formed in a continental rift valley in the southeastern margin of the Tarim plate.