| Located in China's "gold belt" of the construction of the Qinghai gouli region well developed. Magmatic activity in the region frequently. It has a very favorable geological background and the formation of large-very large deposits of geological conditions. Gold deposits have been discovered mainly by the Kunlun fault control, the main ore body located in the Kunlun fault on both sides. This master's thesis on the basis of in-depth and detailed field geological work and microscopic observation room, the use of geological-geochemical combination of working methods, and with the system of economic geology, stratigraphy, tectonic, magmatic activity, element and isotope geochemistry, exploration geochemistry research. Discusses the typical deposit minerals into Guoluolongwa sources, and evolution of ore-forming fluids, analysis of the formation, structure and the relationship between magmatism and mineralization, the initial construction of the causes of deposits in this area (mine) mode. This paper achieves the following main results:1,Through comparative analysis, combined with the intrusive diorite chronology, we believe that the guoluolongwa with gold-bearing quartz veins formation of O-SN occurrence Wanbaogou group, as a low-grade metamorphic volcanic formations, the lithology is mainly chlorite quartz phyllite and slate of silicon;2,According to geological survey and indoor microscopic observation, the system is divided mineralization of this deposit type, that is divided into five categories, namely type phyllite, quartz vein, altered rock type, breccia-and oxide crushing-type, which is most dominated mainly pyrite sulfide quartz veins, followed by curing altered rock-type ore material.3,Different types of ore mineralization of REE geochemistry studies have shown that different types of ore mineralization showed REE patterns, LREE enrichment,ΣLREE /ΣHRE>4. However, different types of ore mineralization Eu, Ce anomaly shown in different type of which ore phyllite Eu, Ce negative anomalies exist (δEu=0.68-1.39;δCe=0.96-1.21); Broken bands with negative Eu anomalies and slightly positive Ce anomaly (δEu=0.67-0.95;δCe=1.01-1.55); Quartz vein was significantly negative Eu anomalies and significantly positive Ce anomaly (δEu=0.56-0.85;δCe=1.23-1.61); Altered rock type has a significant negative Eu anomalies and positive Ce anomaly is not obvious (δEu=0.62-0.77; δCe=1.0-1.09); Breccia-type has a significant negative Eu anomaly and no significant negative Ce anomaly (δEu=0.61-0.70;δCe=0.93-0.96)4,REE range of pyrite is in 0.77×10-6～58.79×10-6;ΣLREE/ΣHREE between 10 to 25, with light REE enrichment;δEu between 0.36 to 0.85, significant negative anomalies, with quartz vein-type ores have similar REE patterns, and significant negative Eu anomalies;5,Formation phyllite and qian Mi rock has a significant negative Eu anomalies and negative Ce anomaly (δEu=0.61-0.67;δCe=1.09-1.53), but diorite Eu and Ce anomalies is not obvious (δEu=0.84-1.01;δCe=0.97-0.99). Comparing different ore types of pyrite, and diorite rock formation, the earth in the ore-forming fluids is primary succession on rock;6,The studies of trace elements in ore formation show that volcanogenic rocks in the area of Au, Ag, As, Pb content is higher; the Cu, Zn, Mo in Sedimentary rocks content is high; R-type cluster analysis and factor analysis have proved Au is enriched with a certain independence in guo luo long gui Gold mine;7,Sulfur isotope analysis showed that pyriteδ34S is 0.20～3.88‰, Average 2.21‰Galenaδ34S is -2.03～5.95‰,average-3.46%o. The mean of all samples in the 0‰. It shows that the sulfur in the ore-forming fluid has characteristic of deep source sulfur;8,Gold lead isotopes relatively uniform, pyrite in Gold-bearing quartz veins 206Pb/Pb, 207Pb/204Pb,208Pb/204Pb changes in the range of 18.057～18.135,15.524～15.585,37.962～38.110; Galena 206Pb/204Pb,207Pb/204Pb,208Pb/204Pb changes in the range of 18.093～18.106,15.542～15.563,37.901～37.919. Data point within the Mantle evolution line and Upper crust Evolution Line. Concentrated in the orogenic evolution of the line neararound. It shows this mineralization is a typical orogenic background;9,Fluid inclusion studies have shown that Ore-forming fluids is the low-temperature, high salinity, alkaline sulfur-rich fluid, the fluid Na+> K+;10,On the basis of these studies shows that guoluolongwa belongs to mesothermal quartz vein type gold deposit in the Orogenic-type gold deposits. And thus established a model of the mineralization. Summarized as follows:Strata form-magma intrusion-deformation-ore fluid flow and in place; The performance characteristics of current. Orogeny to crustal uplift, Role in the geological subjected to weathering, Mining area surrounding the intrusion, Middle strata is residual body. Ore formation control by east and west Faults More obvious. However, this phenomenon is not obvious in the rock, inferred Kunlun fault as the main lead ore Fracture. "Into the" type structure as Contain minerals fracture, Combination of ore-forming elements From Au-Fe, to Au-Cu-Fe, further Au-Cu-Pb-Fe direction of evolution. Area further north from guoluolongwa to Asi Ha mining area. Combination of ore-forming elements from Au-(Cu-Pb)-Fe, to Au-Cu (-Pb)-Fe, again to Mo-Cu (Cu-Mo), in between Should exist the Cu-Au Mine. This law shows that ore-forming fluid may migrate from south to north, from east to west penetration mineralization. Guiding force may belong to construct driven magma-driven, perhaps even a common gravity-driven or three power-driven, deep edge has exploration prospects. |
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