| The epithermal gold deposit has become one of the important sources of gold resources in China, which has important economic significance. However, there is still a large gap between the quantity and the resources of the same type of gold deposits in foreign countries. The Zhangjiapingzi gold deposit located in the Yangtze paraplatform the southwestern margin of the Songpan Ganzi geosynclinal bordering parts of West Mianning gold deposit concentration area of tea shop- Yanyuan Ba folded gold metallogenic belt, is China’s famous Tibet Sanjiang hypabyssal epithermal gold mineralization zone. The deposit after several years of exploration, the local control depth of more than 500 m, the grade to the depth of the high, the depth of the ore body is still rich, thick may be. Although it has been found that the gold deposit(mineralization point) in the area, although the previous studies on the geological characteristics and prospecting direction of the gold mine, but the understanding of the mechanism is not unified; the lack of relevant research information.Firstly, in recent years the field investigation out the research strata, structure, magmatic rocks and ore body characteristics, combined with isotope and fluid inclusion sampling results of Zhang Jia Ping Zi gold deposit ore-forming materials, the origin of ore-forming fluid; and on the plate tectonic into ore drawing theory and mantle derived mineralization theory as a guide, and based on the former research results, to understand the metallogenic mechanism and mineralization characteristics of; Zhang Jia Ping Zi gold deposit, attack attack find deep blind "and provide a theoretical basis; and to provide guidance for the region corresponding to the type of mineral deposit research work. The main results obtained are as follows :(1) ore bodies in the study area are mainly occurred in dolomite, altered dolomite is the main host rock of the gold, its original rock is basic volcanic rock metasomatism. Ore minerals are mainly pyrite, tetrahedrite, galena, sphalerite, chalcopyrite. Ore is stockwork structure and massive structure, which belongs to the low sulfide type ore, main gold carrying mineral is pyrite; wall rock alteration becomes green mud petrochemical, carbonatization, pyritization, silicification and sericitization, limonitization is a product of table, as a sign of prospecting. The Zhangjiapingzi shear schistosity alteration zone is the only host and ore-forming structure, strictly controlling the formation of gold ore deposit and the orebody output.(2) According to the research of C, O, H, S stable isotope and fluid inclusion, the ore-forming hydrothermal fluids mainly consisted of metamorphic water and mixed source of a small amount of magmatic water. The mineralization temperature is 200-280 degrees C, and the mineralization depth is between 1.5-2.4km, and the type of the deposit should belong to the shallow low temperature hydrothermal gold deposit. The gold mineralization occurs mainly in the Himalayan period between 1.54Ma-38 Ma, the main mineralization age is about 25 Ma.(3) Gold deposits in the study area mainly located in our enoxaparin anticline, the West Wing of the Zhang Jia Ping Zi shear schistose alteration change in Triassic, ore body occurrence entirely by the sole control of Zhang Jia Ping Zi ductile shear belt; In gold mineralization enrichment is relatively concentrated part of Zhang Jia Ping Zi ductile shear zone of steep and flat alternating lots, surrounding rock of greenschist formed lots of structural traps and somatic enriched gold deposit is a part; in addition, in the area of small faults, cleavage, joint, foliation and schistose development at, there are also many rich.(4) through the primary halo characteristics, deep still have the possibility of rich ore bodies, it is suggested that the next step to carry out the work of deep deep to find the blind, to expand the results of prospecting. |
