Research Of Ore-controlling Mechanism And Three-dimensional Structure, Yangshan Gold Belt, Gansu

Yangshan gold mine is the largest gold reserves in Asia, Yangshan has also become the hot spots of the genesis research, through the alteration of samples with internal and external research and the construction of the drilling core catalog and the prepara- -tion of 3-D geological map,Guanyinba fault location and occurrence, the result of mapping the surface profile in the United wells have been tested, and its essence is found in a shear fracture zone in limestone, development of a large number of brittle-ductile shear zone within the structure (such as: traction fold, the pressure-shadow, SC foliation,σandδtype structure), the deep structure and surface outcrop of slightly different styles, but belongs to the same tectonic stress field of the structure. Minera- -lization concentrated in and side of the fracture zone, but the distribution of tattered zone with no obvious correlation between the distribution of mineralization and rock, there are some rocks the body even without mineralization, grade deep mineralization mainly showed the depth of that position with the broken belt, which proved a good mechanism of forming the conclusion inversion structure, on the Yangshan Gold Belt deep structure with a new understanding of the mineralization and alteration zones have a more clear relationship between the conclusion that the scope of mineralization and alteration zones are not showing a proposed foreign scholars positive correlation; on the inner strip mining of calcite mineralization derived ore fluid model is not generally considered prior to the "decompression boiling" mechanism, but rather a more complex physical-chemical processes to achieve the multi-period times mineralization ; of the shear zone and surrounding structures within the macro-observation of the phenomenon and found that the depth of Yangshan gold minerali- -zation occurs in the limestone just brittle to ductile transition depth (3km or so); carbon isotope studies suggesting that the main origin of ore-forming fluid were precipitation mixed a little magmatic water, not metamorphic water.