The Characteristics And Causal Analysis Of Pb-Zn In Qiaze, Xietongmen, Tibet

Qiaze Pb-Zn deposits located in the central south margins of Gangdese metallogenic belt of the Qinghai-Tibet Plateau collision orogen and are controlled thrust nappe tectonic system.this paper ascertain the geological Characteristics of stratigraphy structure andhydrology engineering and environmental of Qiaze Pb-Zn deposits, analysis the characteristics of ore body,obtained some of the amount of resources, clear source of ore-forming fluids and metallogenic geological age, determine mineralization mode and establish the type of causes.Qiaze Pb-Zn deposit ore body is hosted in the limestones of Xiala Formation of Lower-Permian, ore body like lenticular and chicken coop out crop in fracture zone of controlled thrust nappe tectonic Mineral combination simple composed of sphalerite+galena+pyrite+chalcopyrite+calcite. The early tages of mineralization is quartz pyrite (pyrite, pyrrhotite and quartz),the main phase of quartz sulfide(galena sphalerite and py rite),late carbonate phase (calcite).Mineralization age in the Eocene-Pliocene.Correspon-ding to formation time of40-26Ma of thrust nappe tectonics system of the Tibetan PI ateau.The study area hydrogeology simple,the medium of geological environment,engine ering geology surrounding rock components more volatile.Higher background of Pb Zn Ag in calcium formations of the Paleozoic sedimentary,the formation of the "ancient source of ore". With full collision the Indian-Eurasian plate in the Cenozoic,region into the intra-continental deformation,the deep material a strong decompression and fractional melting, the formation of large-scale fluid and melt; Occurred during the large-scale thrust nappe structure provides better space for fluid activities,Higher thermal anomalies for fluid activity provides the greatest energy, coupled with the meteoric water involved in the formation fluid,Useful elements in the activation of these fluids in the long-distance transport manipulation to the"source of ore", When the migrated to the appropriate tectonic fractures,due to temperature,pressure,Ph value changes, And the ore-bearing hydrothermal and wall rock metasomatism,ore-bearinghydrothermal fluids in the tectonic system suitable layer precipitated,thus forming Pb-Zn body.Qiaze Pb-Zn deposit is deposition superimposed tectonic hydrothermal transformation type deposits.and subject to the thrust system (guide ore,ore-controlling and even ore-containing)control and formation...