| Laozhaiwan gold deposit, locating in the "Southwestern Golden Triangle" ofDianqiangui, is a large scale, low grade, fine grained disseminated gold deposit. Thispaper, through collecting and arranging the materials of predecessors and combiningwith indoor-identification and experiments, obtained the following majorachievements.The Lao zhaiwan gold deposit is located in the Southwest golden triangle of theYunnan-Guizhou-Guangxi and occurred in a large low grade of fine disseminated typegold deposit of the Devonian altered fine quartz sandstones upon the Gary Don paleouplift unconformity; magmatic activity is not strong in the mining area, a diabasedikes exposed on the Chun Shuwan Ore Section, invasive of the mafic dikes provideschannel to the late hydrothermal activity; the Lao zhaiwan gold deposit's formationcan be divided into diagenesis mineralization period, hydrothermal period andhypergene period. Hydrothermal mineralization can be divided into quartz-pyrite astypical combinations of early stage, quartz-pyrite-sericite combinations of middlestage and stibnite-calcite combinations of late stage.Sulphur of the Yunnan-Guizhou-Guangxi micro immersion type gold deposit ismultiple sources of deep source sulfur, strata sulfur and organic sulfur, and the sulfursource of the Carlin type gold deposits is considered to be host strata. Laozhaiwangold deposit ore sulfur isotope is positive, which is related to initial contamination ofmarine sulfate sulfur, late epithermal sulfur isotopic composition in the lower is mightrelated to marine sulfate sulfur of Contamination relatively less. Lead isotopicfeatures show that the Yunnan-Guizhou-Guangxi Carlin type gold deposit lead isotopeprimary sources for the crust and Orogenic Belt, individual deposits may have amantle-source (deep source of lead), shallow source material to join after deepsource.The Yunnan-Guizhou-Guangxi Carlin type gold deposit fluid of carbon,hydrogen and oxygen isotopic composition of large variation range, ore-formingfluids with multiple sources might mainly about formation water both atmosphericprecipitation mixed fluid(individual deposit might with a deep source of fluidmixing).Carlin type gold deposits of Qinling Mountains region mainly formed inIndosinian-Yanshannian, the Yunnan-Guizhou-Guangxi region formed in lateYanshanian and early Himalayan period while the United States are mainly formed in the Himalayan period; different mineralogenetic epoch reflects differentmetallotectonic settings. Metallogenic thermal condition or the source of heat is thedeep tectonic-rifting abnormal geothermal field, deep structural process is thefundamental of Yunnan-Guizhou(Guangxi) Carlin type gold deposit concentrationarea migration of ore-forming fluids in thermal power, gold mineralization is a formof expression.of the deep structure in shallow crust. |
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