Lead And Zinc. Western Yunnan Paul Pecan Ping V <sub> 1 </ Sub> History Of The Evolution Of The Ore Body Ore-forming Fluid Analysis

Hetaoping skarn-type lead-zinc deposit in western Yunnan province which is hosted in marbleization limestone of the upper Cambrian Hetaoping Formation is located in Hetaoping lead-zinc muti-metal deposit cluster area of Baoshan-Zhenkang lead-zinc-copper polymetallic belt. The deposit is controlled by tectonic. In the past few years, this particular deposit has been receiving increasing attention from researchers, and many results were obtained. Because of lacking of wall-rock alteration characteristics, geochemistry of fluid inclusions characteristics and the history of the fluid evolution, there are many diffents understandings ore genesis and mineralizations. Aim to solve this problem, it is obtained many results through researching for the above aspects in this paper. The results are list as follow:(1)Petrographic observations,temperature results and analysis of fluid inclusion component indicate that the main types of fluid inclusions are NaCl-H20 solution and aqueous inclusions in seven mineralization stages and the shapes of fluid inclusions of Hetaoping are mainly of ellipse and irregular shape. Due to sudden falling of pressure(decompression) and joining of meteoric water, boiling happened in the ore-forming fluid. Generally, homogenization temperature, salinity, density and homogenization pressure of the fluid are stably decreased from early skarn stage to carbonation late stage. Zinc precipitation mainly occur in190～220℃and 7-16Mpa. The mineralization occurr under the epithermal conditions of 0.25～1.75km. So it is epithermal deposit.(2)Inclusion groups analysising show that the ore-forming fluid are rich in Ca2+, Na+, K+, F-,Cl-, SO42- and CO2,H2S,CH4,C2H6. The deoxidize coefficient (R*)in early mineralization stage is 1.14～1.47, and in the late is 1.28.Indicate that the environment of ore-forming fluid in early stage is more deoxidize than late stage.(3)Based on the study, fluid end members are divided into high temperature-low salinity and low temperature-high salinity,and mixing of fluids cause the boiling and sulfide precipitation.(4)Isotope of fluid Inclusions analysis indicate that ore-forming elements were carried by tectonic-fluids from magma or mantle to orogenic belt.