Construction And Application Of Exploration Indicator Of Zhunuo Porphyry Copper Deposit

Zhunuo super-large porphyry copper deposit is located in the western Gangdese metallogenic belt,Tibet.It is the largest porphyry copper deposit in the western Gangdese metallogenic belt.The metallogenic geological conditions,geophysics,geochemistry,remote sensing and other aspects of the Zhunuo ore concentration area(the research area)where the Zhunuo copper deposit is located are very similar to the Zhunuo porphyry copper deposit,but the ore-prospecting effect has been unsatisfactory since the Zhunuo copper deposit was discovered.In order to achieve a breakthrough in prospecting,this paper analyzed the geological features,geophysics,geochemistry,remote sensing and short-wave infrared spectroscopy of the research area in detail,sorted out and extracted the prospecting indicator of Zhunuo porphyry copper deposit,and delineated the target area of the entire research area,obtaining the following understanding:Indicator characteristics of Zhunuo porphyry copper deposit exploration:(1)The metallogenic geological bodies are the Miocene endocentric granitic porphyry and porphyritic monzonite,with high oxygen fugidity(log(fO2)average-22.9,Ce4+/Ce3+ average 83)and high water content(pressure water content at 0.8GPa is 9.2-11.9wt%).(2)The alteration zone from inside to outside is potassization,sericinization and cyanpanization,among which potassization and sericinization are closely related to chalcopyrite.(3)Orebodies on IP performance for low resistance(< 2000 ?.M)high polarization characteristics(> 5%);Characterized by high resistance on magnetotelluric(about 500-1000 ? m)double high conductor(< 300 ? m)characteristics.(4)In the 1:50,000 river sediment,the ore body shows the characteristics of Cu element anomaly greater than 200 ppm,the ore concentration coefficient of porphyry copper mine is more than 8,and denudation degree less than 0.49.(5)The characteristics of the ore body in ASTER remote sensing image interpretation are the spatial coupling of potassization,cypteritization,limonitization,and carbonate alteration.(6)In the short-wave infrared,the ore body shows that Muscovite is dominated by short-wave,mainly varying between 2194 and 2203 nm.The crystallinity is higher and the absorption depth of the wavelength is stronger.According to the porphyry copper ore exploration markers established in Zhunuo copper deposit,thirteen target areas are delineated in this paper.And it is believed that the Cimabanshuo target area has obvious exploration markers and great metallogenic potential.