Huda Gold Mine in lingbao city, Henan Province

Huda Gold Mine is located in Yangping Town, lingbao city City, Henan Province, in the middle of the northern ore belt of Xiaoqinling Gold Field, and is one of the important gold production bases in China. The deposit is located on the NW-trending F5 fault zone, and it is a typical structural altered rock type gold deposit. By the end of 2005, the gold and metal resources in the mining area were 22.854 tons. ..

Huda gold deposit is located in the dome of Xiaoqinling platform in Tailong, Hua Xiong, on the southern margin of North China platform, and in the secondary wuli village anticline in the northern wing of Laoyacha anticlinorium. The metallogenic belt belongs to the northern part of Xiaoqinling gold ore field in Xiaoqinling Mo-W-Au-Fe-Pb-Zn fluorite ore belt.

1. Brief description of mining area geology

(1) stratum

The exposed strata in the mining area are mainly Neoarchean Taihua Group and Quaternary. The lithology of Neoarchean Taihua Group is a set of deep metamorphic rocks, belonging to Neoarchean granite-greenstone belt, which can be divided into four types according to lithologic combination. Granites exposed in the mining area are Sifangou gneiss and Yang Qiyu gray gneiss. Sifangou gneiss of Taihua Group is distributed in the southwest of the mining area, Yangzhaiyu gray gneiss of Taihua Group is distributed in the southeast of the mining area, and Quaternary is distributed in the north of the mining area.

② structure

The fault structures in the mining area are relatively developed, which can be divided into four groups according to the strike, namely, near east-west, north-northwest and near north-south, among which the near east-west fault group and north-northwest fault group are the most developed. The nearly EW-trending fault groups mainly include F5, FI, F6, F7 and F8, among which F5 is the main ore-controlling structure in the mining area. The NNW-trending and NNE-trending faults form * * * yokes, which develop along the NNW direction and are mostly filled with diabase and granite porphyry veins along the faults. There are only 1 faults in the nearly north-south fault group area, which are distributed in Xiaoyugoukou. The fault zone is mainly composed of cataclastic rocks, and some of them are filled with corresponding time veins.

③ Magmatic rock

The dikes in the mining area are developed and widely distributed, mainly including granite pegmatite, diabase and granite porphyry. Granite pegmatites are mostly distributed in vein, dendritic, irregular and small rocks, with different scales and exposed areas ranging from several square meters to hundreds of square meters. Diabase is the most developed dike in this area, which occurs in the form of veins and is most developed in the northwest direction. Granite porphyry is well developed in this area, and it is filled with veins in the NNW-trending faults.

2. A brief description of the characteristics of the deposit

1 ore body characteristics

The distribution of ore bodies in Huda Gold Mine is closely related to the distribution of gold-bearing quartz veins. Gold ore bodies mainly occur in gold-bearing quartz veins, and ore bodies are strictly controlled by gold-bearing quartz veins. Its shape, arrangement and occurrence are basically consistent with those of gold-bearing quartz veins. The ore bodies are distributed in groups and arranged in parallel in the shape of geese, which has the characteristics of sharp extinction and reappearance. The main gold ore bodies are distributed in F5 fault structure belt, mostly in vein, lenticular and layered form, and are buried deeply, belonging to concealed ore bodies. Rich and thick ore bodies mainly occur in the dip angle of fault structure belt, strike turning and the intersection of two fault structures.

Specimens were collected from F5 mining area in Hu Da mining area. There are two main gold ore bodies in F5 ore-bearing structural alteration zone, numbered F5- 19-III and F5-22.

F5-19-Ⅲ ore body: located between 1 ~ 18 lines, the length of ore body is1235m, the maximum controlled dip depth is1488m, with an average of 460m, and the thickness of ore body is 0.52 ~/kloc. The dip angle of the ore body is 330 ~ 350, and the dip angle is 28 ~ 44, with an average gold grade of 4.69g/ton. ..

F5-22 ore body: located between the 4 ~ 14 line, the ore body is 576m long, the maximum controlled dip depth is1504m, with an average of 640m, and the ore body thickness is 0.58 ~10.27m, with an average of 2.89m. The ore body is irregular and lenticular, with simple shape. The dip angle of the ore body is 340 ~ 360, the dip angle is 3141,and the average gold grade is 3.61g/t. ..

② Ore type and structure

The type of gold-bearing ore in the area is mainly gold-bearing quartz vein ore mineralized by polymetallic sulfide, followed by a small amount of polymetallic sulfide mineralized cataclastic rock, mylonite and wall rock altered ore. The content of metal sulfide in gold ore accounts for about 5% of the total mineral content, which belongs to less sulfide ore. The gold minerals in the ore are mainly natural gold.

Ore texture includes authigenic-semi-authigenic granular texture, irregular granular texture, metasomatic texture, clastic texture, mylonite texture and fractured texture. Ore structures mainly include disseminated structure, breccia structure, granular structure, massive structure, reticulated vein structure and banded structure.

Specimen name: The ore number of the chronological gold deposit is DB0 10- 1 Yanshanian.

Atlas of large ore specimens from typical mines in China

The ore sample was collected from F5 ore block in Hu Da mining area. The surface of the specimen is grayish brown with irregular granular, fractured and massive structures. The ore minerals are mainly pyrite, chalcopyrite and natural gold. Gangue minerals are mainly seasonal. The gold grade is 8.7g/ton.

Genetic types of Huda gold deposit in lingbao city, Henan Province: Post-magmatic hydrothermal type (structural altered rock type)