Study On Metallogenic Regularity And Metallogenic Prognosis Of Copper Deposits In Yimen Copper Deposit, Yunnan Pro

Tongchang mining area, which sits in Yimen, Yunnan Province, mainly scattered in three places following:the southwest of Yangtze paraplatform、the middle of the Wuding- Yuanjiang faulted trough in Kunyang Rift and the western margin of Yimen graben basin formatted in the proterozoic. Tongchang copper ore deposit is one of the most important deposits in Yimen copper belt. After many years of exploitation, Yimen area is facing the crisis of copper ore resource shortage. Therefore, creating a deep and periphery prospecting in Yimen mining area has a theoretical and practical significance to improve and practice the prospecting theory, what else, this can help implementing sustainable development of mine in this district.Based on the analysis of previous studies, combined with the actual production requirement, through geological field work, as well as the further research of regional ore-forming geological background, this paper systematically summarized the geological features such as stratigraphic sequence and structural characteristics in this area. According to some characteristics which including the enrichment and distribution of copper, it takes different ore section as research subject to analysis and summary its geological characteristics of ore bodies. Utilized the studies of stable isotopes and the ore-controlling factors, summarized the deposite mineralization enrichment features. On the foundation of systematically summarized the deposites distribution and ore-controlling factors, combined the geological and geophysical-geochemical methods, clearly ascertain the indicators for deposites in this research area, optimization selected the ore-prospecting target area.By further study of regional metallogenic geological background and mining area geological characteristics etc, this paper comprehensively expounds the geological characteristics of ore bodies, put out that the ore deposits can be divided into sedimentary-digenetic deposit (Tongchang-style deposit) and hydrothermal vein type deposit (Dajianshan-style deposit), the former ene is obviously controlled by strata and lithology, and is stratiform or stratoid in the lyard siliceous dolostone, the latter is controlled by tectonic, and located in Luoxue and Etouchang Formation. Two types of ore bodies are significantly different in mineralization features, mineral composition and mineral fabric etc.The carbon isotope and oxygen isotope of sedimentary-diagenetic deposit are consistent with the surrounding rock, whose minerals mainly comes from stratum, Bacteria reducing sulfate in the sea is the main source of sulfur according to the analysis of sulfur isotope; the ore-forming materials of the hydrothermal vein type deposit show the typical characteristics of deep source. Analyzed the source of ore-forming materials and ore-controlling factors, and then summarized mineralization regularity. By the assemblage of sulphide and the comparative study with actual geological setting, the vertical zoning of mineralization is obvious to us, so, we know that the minerals is generated under the multiphase and different mineralization. On this basis, illustrating the superimposed mineralization in this mining area, and dividing the section of mineralized types according to different combination of mineralization, finally, summarized its distribution in space.Synthesized the above, both with the analysis to the characteristics of geophysical and geochemical abnormity, creating markers for ore finding, selecting three prospecting targets, that is the prospecting target of Dajianshan-style deposit in north of No.20 line, the prospecting target of Tongchang-style deposit in northwest side of No.15-20 line, and the prospecting target of Xiaomashan.