Sichuan Province The Shimian Dashuigou Pilsenite Geochemical Characteristics And Mineralization

The Sichuan Dashuigou Te deposit which is as far only independent tellurium deposit in the world have a great value for geochemistry research.In this paper, the author attempts to study the regional geological knowledge, collect database on past mining, analyze the geological setting of the region. The main subjects of the present study could be summed up into four fields:(1) the background of regional geology (2) geology and mineral deposits characteristic (3) geochemical characteristic of deposit (4) mineralization and process of deposits.The major conclusions of this study is summarized as follows:1. The study area is located in the western margin of the Yangtze block, and in the central-northern part of the Luding tectono-metallogenic zone, which make the regional geological structure is much complicated. Tectonic history of frequent impetus for the formation of deposits and space.2. Basic on systemically investigation for the rock in study area, we found that these rocks commonly contain ore with large amount of schist and marble. Mining ore contains mainly Tetradymite dolomite veins, and the formation of ore may be related with alteration through analysis of carbon and oxygen isotope.3. Geochemical analysis of the rocks of ore bodies indicate that the ore bodies is the mantle protolith volcanic rock-the basalt.4. Ore material was derived from the mantle, which is related to Mesozoic tectonic-magmatic activity5. Geochemical investigation reveals that the ore-forming fluids originated from the mixing of magmatic, formation and meteoritic water.6. The reduction of temperature, pressure and pH directly affect the migration of ore-forming fluids and the precipitation of ore-forming elements. The mixing of different types of fluid have an influence on temperature, Eh value, PH value and other parameters, so as to precipitate minerals from ore-forming fluids. Furthermore, immiscible activity of deferent fluid and various chemical reactions during the mixing can lead to mineral deposit. 7. The genesis of the marine is the construction-hydrothermal type and the marine volcanic eruption-metamorphism type.