Metallogenic Condition And Prediction Of Xiongcun Copper-gold Ore Deposit In Tibet

This paper takes Xiongcun copper-gold ore deposit, which is located in XieTongMen County of Tibet, as its research object. Through analyzing the geological and geochemical feature, author probe into the genetic classification and controlling requirements of this deposit, providing an exploration orientation for future.Xiongcun copper-gold ore deposit is located in Gangdese Metallogenetic Belt with a large scale. The ore body mainly exists in the second lithoid unit's tuffs and the third lithoid unit's dacite tufa of the Cretaceous Volcanic Stratum, which are not only mother rock but also mineralized body. The structure of "Two Faults with one Fold " controls the ore body with the existence of intensive structure movement. The ore body is mostly produced in the secondary fracture zone of North-West direction. There are intensive structural and magmatic hydrothermal movement with obvious zonal surface shape alterations, which are demonstrated by silicified function, sericitization, potassium, epidotization, hornstone, etc. The ore structural fabric mainly behaves in form of filling action with minerals such as pyrite, chalcopyrite, salenite, blende and electrum, which typomorphic feature shows a hypothermal pattern of metallogeny.Through the study of characteristic of macroelement, microelement, rare-earth element, oxyhydrogen isotope, sulfur isotope, lead isotope, fluid inclusion etc, a conclusion can be drawn that metallogenic substance comes from the upper mantle with mixing of some substance from the upper crust latter. It is likely to have the same source with the surrounding rock. Their structural environment is mainly volcanic arc. The formation of the ore deposit is relevant to the structural activities. Both the metallogenic pressure and temperature are relatively lower, and the genetic classification of the ore deposit is epithermal deposit. The formation time of the ore body is mainly the late Himalayan, and the formation is relevant to the structural movement of Himalayas.Tthrough field inspection and indoor information collection, author expounds the controlling factors of Xiongcun ore deposit, and determines the metallogenic principle. The local volcanic tuff and the secondary structure mainly control the formation of this ore deposit, which metallogenic principle is relevant to the tectonic movements.In this paper, suggestion for the future work is given according to analysis of geochemical and geophysical data. Through time domain induced polarization method,it is obviously that this copper-gold ore body has a vast scales and a great thickness with a depth of more than two hundred meters. Soil geochemical measurement of one ten-thousandth scale indicates that the anomalies of gold, stiver, copper, lead have features of high intensity and well-lapped forms. Xiongcun ore deposit has great metallogenic potential.