| Laoling metallogenic belt is an important gold and nonferrous metal metallogenic belt of jilin province.Yingmencha copper(molybdenum) deposit is located in the central part of laoling metallogenic belt and the tectonic location belong to east section of northern margin of north China craton. Mining strata is simple and located in Zhenzhumen Formation of Laoling Group. The main structure of the mining area is fracture with less fold development which goes mainly from north to east. In the mining area the magma is quite active and the intrusive rocks mainly include rock strain, granodiorite-porphyry of the dyke, diorite and diorite porphyrite, etc.Granodiorite-porphyry is the host rock of ingmencha copper(molybdenum) deposit. Petrography, chronology and rock geochemical study shows that the rocks belong to Quasi aluminum- weakly peraluminous high potassium calc-alkaline series, I type granite.The tectonic setting of Rock formation is subduction environment. The result of granodioriteporphyry zircon LA-ICP-MS U-Pb dating shows that rock age of 168±1Ma.Yingmencha copper(molybdenum) ore bodies that has been found mainly distributed in the west of the mining area and can be better oberved and controlled relative to the eastern project. Yingmencha bifurcation copper(molybdenum) deposit ore minerals mainly include chalcopyrite, pyrite, molybdenite, sphalerite,etc.And gangue minerals mainly includes quartz, biotite,sericite feldspar, etc. Ore minerals have euhedral-subhedral granular structure, fragmented structure, account structure, massive structure and vein structure etc.Wall rock alteration in the Mining area has the characteristics of surface type alteration, such as silicide, green rock lithification, potassium feldspathization and sericitization,.The ore-forming process is divided into oxide phase( Ⅰ), quartz-molybdenite stage(Ⅱ), quartz- polymetallic sulfide phase(Ⅲ), carbonate phase(Ⅳ), and quartz- polymetallic sulfide stage is the main ore-forming stage.The experimental results show that the peak temperature range of gas-liquid two-phase inclusions is 260-320℃,halite-bearing three phase inclusions is 290.2-338.3℃, the metallogenic fluid has the characteristics of high temperature, metallogenic pressure range is 40-75 Mpa, and metallogenic depth is 1.3-2.5km. Metallogenic material mainly includes Mantle source of sulfur with a small amount of sulfur in the earth’s crust. The main Source of ore-forming fluid is magmatic water with other fluid such as rainfall.Througu a comprehensive study of the results of the above analysis. It is a porphyry copper(molybdenum) deposits. Its minerogenetic geotectonic background is subduction environment of the Pacific plate. The mineralization period slightly later than emplacement period of rock. |
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