Geological Characterisitics And Metallogenic Prospecting Of Zheng Guang Au-Zn Deposit, Heilongjiang Province

The tectonic framework for research area is composed by Peleozoic NW-trending tectonic and NE-trending secondary tectonic, and formed NW-trending, NE-trending and SN-trending after successive tectonic activity. Combining magnetic anomaly charactericstics of Duobaoshan-Zhengguang, and development of volcanic brecciated rock and volcaniclastic rock, we consider that volcanic and subvolcanic activity exist in the area, and provide channel and space for migration and conservation of Au-Zn oreboies.According to further research on characteristics of metallgenic geology, and metallogenic regularity, we conduct prospecting to east of Zhengguang Au-Zn deposit, deep-seated No. II orebody, and tectonic activity area between No. I, IV orebodies and No. II orebody. We predict that the area have potential of searching Au and Cu deposit in deep, and potential of breakthrough 50 t Au in shallow part.The U-Pb chronology of various vein rocks crossed orebodies from the Zhengguang Au-Zn deposit indicate that Au mineralization occurred earlier than 454 Ma. Combining results of chronology from Duobaoshan deposit, Zhengguang Au-Zn deposit is controlled by island arc of subduction of Paleo-Aisa, which is approximate to same period or a little late with Duobaoshan Cu-Mo deposit and Cushan Cu deposit.The research on characterisitics of geophysics and deposit indicate that Zhengguang Au-Zn depsit is characterized by low magnetism-mid polarization. The oreboides are characterized by weak magenetism because of hydrothermal alteration.The Zhengguang Au-Zn deposit is belong to epithemal type deposit, and different from tectonic alterated rock type gold deposit from characterisitics of mineralization, vein system, alteration. However, Zhengguang Au-Zn deposit is belong to mid sulphide gold deposit, transiton type from high sulphide to low sulphide with Zn mineralization.The Duobaoshan ore-concentrated area is an important porphyry type Cu-Au-Mo metallogenic belt in the north of China, which is located in superposition between Paleo-Asia metallogenic tectonic domain and Pacific metallogenic tectonic domain. It is transition area between Daxinganling arc-basin system and Xiaoxinganling arc-basin system. The meatallogenic condition is preponderant, and mineral resources are abundant. The Zhengguang Au-Zn deposit is located in the south-eastern of Duobaoshan metallogenic belt, and about 10 km away from Duobaoshan porphyry type Cu-Mo deposit to NW-trendign, 5 km away from Cushan Cu deposit to NW-trending. The relation of metallogenic age with Duobaoshan Cu-Au deposit and prospecting direction in deep is not clear. The paper select Zhengguang Au-Zn as research object, which is feeble on theoretical research, and prospecting work made breakthrough in this area. According to characteristics of mineral deposit, ore-forming fluid, geophysics, geochemistry, and diagenetic age and tectonic setting, we determined metallogenic type further, and discuss prospecting direction. The main advance achievements from this study area are as followings.