内蒙古道伦达坝铜多金属矿床特征研究

Geology and Metallogenesis of Daolundaba Copper Polymetallic Deposits,Inner Mongolia

通过详细的矿床地质研究,基本厘清了矿床的主要控矿因素(赋矿围岩、控矿构造、岩浆岩特征),围岩蚀变类型、矿体分布特征、矿石组合及可能的成矿过程,认为道伦达坝二道沟矿区铜多金属矿为中高温热液脉型,受花岗岩体外接触带板岩层内北东向断裂及褶皱构造的控制,前进场黑云母花岗岩岩体在形成演化过程中,可能为成矿提供了成矿物质及其集聚和运移的热动力条件,而围岩地层提供的金属元素保证了矿体的规模和质量。

The Daolundaba copper polymetallie deposit is located in Xiwuqi, Xilinguole Union of Inner Mongonia. It lies on the west side of southern Daxing＇anling ore belt, which is tectonically enclosed by the Siberian Block to the north, North China Block to the south and Songliao block to the east. The deposit is hosted by lower Proterozoic biotite amphibolite （ Pt1by） , upper Permian Linxi formation sandy slate （P2/） and the Hercynian Qianjinehang bio- tite granite. There are about 136 ore veins, striking NE and dipping south with angle varying between 20° and 50°. They are controlled by the NE to NEE-striking Mishengmiao anticlinorium as well as a series of secondary NE-, NEE- and nearly EW-striking faults along the contact zone between the Linxi formation and Qianjinchang granite. The alteration includes silieification, beresitization, carbonatization, chloritization, kaolinization, potassic alteration, greisenization, fluoritization and tourmalination. The silieification, greisenation and fluoritization are strongly related with the mineralization of the deposit. The major metallic minerals are pyrrhotite, pyrite, wolframite and eassiterite containing copper, zinc, tungsten and stannum. Detailed studies on wall rock lithology, structural control, magma evolution, alteration and mineralization style, ore mineral paragenesis have been conducted. Based on the detailed investigation, it is proposed that the Daolundaba copper polymetallic deposit is a typical mesotherreal to high temperature hypothermal vein deposit. It is suggested that the Qianjinchang granite provides thermal driving force for the transport of the ore-forming material and the Linxi formation is the source of the metal.