Characteristics of regional gold and silver enrichment in Nanling area

The geochemical background distribution of Au, Ag, W, Sn, Pb, Zn and other elements in the study area changes greatly. Among them, the geochemical background values ??of Au and Ag are close to the national background, and their geochemical distribution is extremely inconsistent. Uniform, with a high degree of dispersion (Figure 3-1, Figure 3-2). The regional geochemical anomaly results circled in this study are basically consistent with the conclusions of Hu Yunzhong (2006) in the book "China Regional Geochemical Fields and Their Relationship with Mineralization". In the Yangtze Block and the South China Orogenic Belt, Surrounding the Sichuan Basin, Guizhou and northwestern Hunan, a very large annular Au and Ag geochemical anomaly belt is formed, covering five geochemical provinces including Western Hunan, Western Guangdong-Eastern Guangxi, Yunnan, Guizhou and Guangxi, Western Sichuan, and Shaanxi-Gansu-Sichuan. Covering an area of ??800,000 km2, it has constructed a unique Au and Ag geochemical model with the following characteristics:

(1) The Au in the western Guangxi and central Hunan-Nanling areas has a high background trend. Au geochemical anomalies are mostly distributed in the EW, NE and NEE directions. Among them, the anomalies in the EW direction are the most eye-catching. Au abundance is high, there are many anomalies, and the scale is large. Au mineralization concentration areas are mostly located in anomaly areas (zones) Among them:

1) The Au geochemical anomaly area in Dayaoshan and Huaiji Basin in eastern Guangdong and western Guangdong is one of the largest Au geochemical anomalies in China. Large and medium-sized gold particles are distributed in the anomaly area. The deposits include: Yunrongding Gold Mine in Teng County, Guidong (medium-sized), Zhanggongling Gold, Silver, Lead-Zinc Mine in Hezhou City (medium-sized), Longtoushan Gold Mine in Guigang City (medium-sized), Changkeng Gold Mine in Gaoyao, western Guangdong (large-scale) , Fuwan Gold Mine (large), Hetai Gold Mine (large), Yunxi Gold Mine (medium), Gaocun Gold Mine (medium), Sanwei Gold Mine (medium), etc.;

Figure 3- 1 Gold geochemical map of the Nanling area

Figure 3-2 Silver geochemical map of the Nanling area

2) Au geochemical anomaly area (zone) in Yuanzi (Xuefeng Mountain), northern Hunan , the large and medium-sized gold deposits distributed in the abnormal area include: Shenjiaya Gold Mine (large) in Yuanling County, northern Hunan, Dujiaping Gold Mine (medium), Woxi Gold Antimony and Tungsten Mine in Taoyuan County (large), Xichong Antimony Gold Mine in Taojiang County Mine (medium size), Hongjiang City Daping Gold Mine (large size), Tuanziping Gold Mine (medium size), Xinhua County Qingjingzhai Gold Mine (medium size), Xinshao County Longshan Gold Antimony Mine (medium size), etc.;

3) The Au geochemical anomaly area in western Guangxi is distributed in the Fengshan County Jinya Gold Mine (large), etc. In addition, in areas such as northern Guangdong, southeastern Guangdong, southern Guangdong, and eastern Guangdong, Au anomalies are smaller in scale, mostly in the shape of beads and isolated islands. The distributed gold deposits include: Zhongsu gold and silver mine (medium-sized) in Bobai County in southeastern Guangdong, Bobai County Baixian Jinshan gold and silver mine (medium size), Lianjiang City Pangxidong silver and gold mine (medium size), Xinyi City Dongkeng gold mine (medium size), Heshui gold mine (medium size), Sanchaao gold mine (medium size) in southern Guangdong Medium) etc.

(2) Ag is an associated element in various metal mineralization activities (copper, lead polymetals, precious metals, rare metals, etc.). It can also form independent deposits and is also easily adsorbed and enriched by organic matter. In the carbonaceous rock series, its distribution is relatively complex. The Ag background in regions such as western Hunan, southern Hunan, central Guangxi, northern Guangdong, and southern Jiangxi is higher than other regions. The most eye-catching Ag geochemical provinces (anomalous areas and zones) in the study area are:

1) Ag geochemistry of southern Hunan-northern Guangdong-southern Jiangxi-dong Guangxi at the junction of the four provinces of Hunan, Guangdong, Jiangxi and Guangxi Province, Ag anomalies are concentrated, high-intensity, and large-scale. This area is the core area of ??the Nanling metallogenic belt and is also the area with the most concentrated distribution of Ag, Pb, Zn, and Cu polymetallic ores and W and Sn ores in my country.

Silver polymetallic deposits and famous tungsten-tin deposits include the Shizhuyuan tungsten-tin-molybdenum-bismuth mine (super large), Bailashui tin mine (super large), Hehuaping tin-bismuth mine (large), and Xintianling in Chenzhou City, Hunan Tungsten-molybdenum-lead-zinc-copper mine (large-scale), Hongqiling tin-lead-zinc-copper mine (large-scale), Pheasant tail tin-silver-gold-copper-lead-zinc mine (large-scale), Jinchuantang tin-bismuth-tungsten-zinc mine (large-scale), Nanfengao mine Silver mine (medium size), Linwu County Daping tin polymetallic mine (very large), Yizhang County Yaogangxian tungsten tin silver mine (large), Guidong County Zhuyuanli tungsten and bismuth mine (large), Lanshan County large Ao tungsten-tin mine (large-scale), Guiyang County Huangshaping tin-lead-zinc-iron mine (large-scale), Baoshan lead-zinc polymetallic mine (large-scale), Changning Kangjiawan lead-zinc-gold-silver mine (large-scale), Dafang silver-lead Zinc polymetallic mine (medium-sized), Jiangyong County Antanling lead-zinc-silver mine (medium-sized), etc., Renhua County Fankou lead-zinc mine (super-large), Qujiang County Dabaoshan copper-lead-zinc polymetallic mine (super-large), etc. Large), Yaoling Tungsten Mine (large), Lechang City Keng-Youdong Uranium Mine (very large), Ruyuan County Tianmen City Zhang Tin Mine (large), Shixing County Shirenzhang Tungsten Tin Mine (large), Meiziwo tungsten tin mine (large), etc., Xihuashan tungsten mine (large), Piaotang tungsten mine (large), Chongyi County Maoping tungsten mine (large), Chikeng silver-lead mine (medium) in Dayu County, Jiangxi , Maocaogou silver-tungsten mine (medium-sized), Shangyou County Jiaolibei silver mine (medium-sized), etc., Guangxi's Zhongshan County Coral Tungsten-tin-Copper-Zinc Mine (large-scale), Gongcheng County Laochang Lead-Zinc Mine (large-scale), Hezhou City Zhanggongling gold, silver, lead and zinc mine (medium size), etc.;

2) Qianxi Guizhou-Northern Hunan Yuanzi (Xuefeng Mountain arc-shaped structural area) Ag geochemical anomaly area (zone), roughly divided into two lines Ag anomalies are composed of NEE-NE-NNE zonal distribution. This anomaly area is distributed from southwest to northeast with mercury mines, manganese mines, antimony mines and gold mines, such as the Xiaokezhai mercury mine (medium size) in Tongren City, Guizhou, cold Fengdong mercury mine (medium size), Meizixi mercury mine (medium size), Yangdong mercury mine (medium size), Tianba mercury mine (medium size), Hunan Xinhuang County Hotel Tang mercury mine (large size), Fenghuang County Baiyabi Mercury Mine (large), Jiangzhai Mercury Mine (medium), Huayuan County Minle Manganese Mine (large), Motianling Manganese Mine (medium), Huitong County Dalong Manganese Mine (medium), Luxi County Yezhu Manganese Mine (medium), Anhua County Zhazixi Antimony Mine (large), Tongxin Antimony Mine (medium), Taojiang County Wangjiachong Antimony Mine (medium), Banxi Antimony Mine (large), Xichong Antimony Gold Mine (medium), Taoyuan County Woxi Gold Antimony Tungsten Mine (Large-scale), Shenjiaya Gold Mine in Yuanling County (Large-scale), Daping Gold Mine in Hongjiang City (Large-scale), etc.;

3) Guangxi Hechi-Liuzhou Ag Geochemical Province, spreading NW, northwest section The abnormal concentration center is located in the Nandan area of ????Hechi. Nandan County Tongkeng tin-lead-zinc mine (very large), Changpo tin-lead-zinc-silver mine (very large), Longtoushan tin-lead-zinc-silver mine (very large), Lamo zinc-copper mine (large-scale), Mangchang tin-polymetallic mine (large-scale), Hechi City Porcupine Po antimony polymetallic mine (large-scale), etc.; the abnormal concentration center of the southeastern section is located in the Liuzhou-Wuxuan area, and no large deposits have yet been discovered , there are only some small and medium-sized manganese mines, lead-zinc mines, etc. in the area, such as Fengyan lead-zinc polymetallic mine (medium-sized) in Wuxuan County, Shuicunduo copper-zinc mine (small-scale), Huayuling lead-zinc mine (small-scale), Jiuyan Zinc mine (small), etc.