| Danba is in the particular Songpan-Garze Orogenic belt,Belong to the intersection of four tectonic system that is composition of the Longmenshan Tectonic Belt,Tectonicof Sichuan and Yunnan,and Qinghai-Tibet-Yunnan-Myanmar-Indonesiaη-type structure which have a long history as mineralization.Yanzigou gold deposit is located in the east of Xian-shuihe fault and the nuclear of Vault body.The deposits are mainly in the fourth of Devonian Weiguan group carbonaceous phyllite lines. According to the original mineral assemblages.Ore types are mainly made of native gold-pyrite and oxidized ore.Based on ore body characterister,ore types can be divided into carbonaceous phyllite layered-like layer and the quartz vein type .In this paper, the work consists of the field investigation and laboratory research, including geological survey, mapping, orebody recourse, trenching and catalog design,old underground tunnel catalog, systematic sampling (including fundamental analysis, portfolio analysis sample,scale section samples, ore samples, Inclusion samples,Oriented structure samples, etc.), and a lot of specific work which contain collect data of joints, faults, folds, crumpled, a lot of field sketches and photographs,etc.Using computers and experimental equipment to complete the rock-ray identification, electron microprobe analysis, such as joints and fault data processing, measurement and fluid inclusion analysis.Now author has known the basic geology of the deposit that include the mine's strata, magmatic rocks, ore body shape, orientation, mineralization, wall ore body and surrounding rock characteristics, ore mineralogy, wall rock alteration characteristics, mineralization of epoch, ore-controlling structures and characteristics of fluid inclusions in minerals,all have a basic understanding about the type of the deposit, metallogenic conditions and With a preliminary understanding of the gensis of deposit. And the deposit is the micro-disseminated gold deposit-Carlin-type gold deposit.The main of ore structure are vein, disseminated, banded, striped and lamellar, in addition some place have agglomerate, breccia (breccia structure), honeycomb-like etc structure.The microstructure of minerals have the crystal structure that formed by the crystallization,account formed by account structure, biological structures formed by bio-mineralization and deformation structure that formed by tectonic stress. Sulfide and Sulphosalts is the main of ore material and components,followed by mineral oxides and a small amount of natural elements.It can be obtained from the analysis of the ore-forming conditions stratiform or layer-like orebody is controlled by intralayered fractured belts. Gold mineralization mainly occurs in physical and chemical conditions with high temperature (285~295℃), shallow depth(0.11~0.92km), low density (2.22~9.21wt% NaCl), and low salinity (0.75~0.85g/cm3);The controlling structures are conjugated faults of NW-SW and NE-SW-trending faults as well as intralayered fractured belts formed by extensional shear faults .The verin-type ore body is mainly controlled by shear echelon vein,and the carbonaceous slate is host rock, and the ore body has a characteristics of stratabound layer; magmatic rocks ore-forming have closely related to the mineralization, that is, it not only provide heat for mineralization, but also provide some ore-forming material.
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