Geological Features And Metallogenic Prognosis Of Binghugou Gold Deposit In Huadian Area,Jilin Province

Binghugou Gold Deposit is located in Huandian area, Jilin Province, 105 kilometers away at SE120°. It lies within the Archean Longgang landmass in the eastern part of the northern margin of the North China platform and the middle of Huinan—Huadian—Helong Au-Ag mineralizaton Belt, where magmatic and tectonic activities occurred frequently and is favorable ore-forming geological conditions.The research area is a high-grade metamorphic region formed in the Archaean era, and the main rock types belong to the Archaean crystalline basement, which accounts for around 70% of the total rock volume; this shows that the Cambrian(∈1) and Triassic(T3) strata occur as veins sporadically, and the rocks mainly include sand-slate, sandstone and conglomerate.The major structure is Majiadian—Sandaoliuhe—Wudaolazihe NW-trending ductile shear belt, known as the major ore-controlling structure within the area, while the secondary one is Jiancaogou-Binghugou-Damalugou NE-trending ductile shear belt. The No.V breccia occurs in the interjunction of NW-trending and NE-trending ductile shear belts.The main magmatic rock type is monzonitic granite, followed by TTG formation complex in Sandaoliuhe. The metamorphic mediate-mafic intrusions mostly occur as relics, dykes and veins.Gold orebodies occurs in seismic breccia in the area. Under the joint control of the NW-trending ductile shear belt and cryptoexplosion breccia, the surface mineral alterations mostly show a zonal or planar distribution, and occur as dense branch veins in the depth. The orebody shows a sign of expansion, contraction and end-to-end alignment, and occurs as a ―curved‖ mineralized belt. The control zone is 360 m long and 4.0~17.2m wide, the depth is greater than 400 m, the ore vein extends along the NE direction, and the dip angle is greater than 65° but less than 80°. The primary ore textures mainly include cataclastic, granular and metasomatic corroded structures, followed by colloidal poikilitic structure. The ore structure consists mainly of brecciated structure, disseminated structure, thin-vein and stockwork structure and nodular structure. The mineralization mostly involves ferritization, pyritization as well as a small amount of galena mineralization, blende mineralization and brass mineralization. The wall rock alteration occurs mainly as surface alteration, commonly appearing as silicification, chloritization, kaolinization, sericitization, and carbonatization, followed by epidotization and red feldspathization. Due to the lack of obvious zonation, the mineral alterations have a gradual transitional relation each other, and gold mineralization is concentrated slightly in the sections where there is a strong mineral alteration.The mineralization and alteration characteristics indicate that the Binghugou gold deposit is a meso-epithermal hydrothermal cryptoexplosion breccia-type gold deposit. Pyritization, galena mineralization and sphalerite mineralization in the rocks are the most direct clues for prospecting. The alteration assemblage in the rocks that is composed of ferritization, silicification, sericitization, kaolinization and chloritization heralds the occurrence of gold mineralization. The interjunction of multi-group structures, the dense outcropping of intermediate and acidic dykes, and the visibility of Au element in a relatively large-scale pedogeochemical anomaly area where there is an obvious concentration center are indirect clues for prospecting.