METOLLOGENIC CONDITIONS FOR GOLD DEPOSITS IN THE NORTHWEST SICHUAN PROVINCE

The northwest Sichuan province is one of the key regions where the primary gold deposits dominated by the micro-disseminated type of gold deposit are concentrated,such as the large and medium sized micro-disseminated gold deposits at Lianhecun,Gala,Jinmuda etc.and the metallogenic conditions for primary gold deposits is prospective.The study area is situated at the passive continental margin of the east Palaeo-Tethys margin.Here is the stable contiment-margional bay or close bay tubulent basin sedimentary environment.Gold is primarily enriched in the turbidite which was exposed to low temperature dynamic metamorphism during Indo-China period and becomes the source bed of the micro-disseminated gold deposits and magmatism occurs at the margional cataclastic zones as tectonic-magmatic zones and is associated with gold and poly-metal ore.The tectonic movement supply heat source for formation of the gold deposits.The gold deposits were formed under the bi-directional shrinked orogenic backgroumd and controlled by the britle-ductile shear zones.Remote sensing techniques are combined with geochemical survey for location of the gold ore prospecting targets.