Geological Characteristics And Genetical Analysis Of Sandaocha Goldfield In Jiapigou,Jilin Province

Based on the sufficient gathering,researching and analysis of the previous data and the combination of scientific research and practical production,the paper conducted a comprehensive research by using multi-theories of stratum,structure,deposit,geochemistry,and remote sensing geology.Numbers of ore mineral samples are collected for carrying on the test tasks such as thinned polished section identification,microelement analysis,inclusion thermometry,and inclusion composition analysis.Meanwhile,primary halo survey in geochemical exploration and remote sensing image processing are carried out for geology interpretation.By combining the principle of the known ore body extension arrangement and the new metallogenetic regular,the prospecting project deployment scheme is suggested to explore the new hidden ore body successfully.The Jiapigou gold deposit occurred in the northwest trending ductile shear?brittle?zone which located in the platform-side in geosyncline-platform edge tectonic activity zone between the Hing-Mong orogene and the North C hina platform.It is a high grade metamorphic complexes area.The Sandaocha gold deposit is one of the typical gold deposits in the metallogenic belt,and the ore body is mainly auriferous quartz vein.The mineralization is d ivided into four stages:Q uartz-Pyrite stage,polymetallic Sulfide?mainly cataclastic pyrite?-quartz stage,late-polymetallic Sulfide-Quartz stage and Q uartz-Carbonate stage.The data shows that the level fluid inclusions:Sandaocha gold deposit develop?CO₂-H₂O fluid inclusions,III CO₂ fluid inclusions,and type IV inclusions.The homogenization temperature of fluid inclusions is 130.9 to 327?,estimate the mineralization depth range is 1.36².67km,the source the main mineralization stage ore-forming fluid is magmatic water and the late stage is atmospheric water.The contact zone between amphibolite and surrounding rock is the main space for ore body occurrence.By combining the metallogenic stage of ore bodies with the sequence of mineral generation and previous related data,the occurrence and location of ore bearing structural fracture zone and ore bearing vein are effectively displayed.