The Yuanmou Regional Geological And Geochemical Characteristics And Mineralization

Located in the west edge of Yangtze Plate, Yuanmou region is complicated in geological structure, in which the fault richly grows, frequent magmatic activities, wide for deformation and metamorphism, rich in mineral resources, popularized in mineralization, it's much lower for research extent in previous geological ore-exploration, there's much greater potentiality for ore-exploration inside. By selecting this region with bright prospect, this paper researches and observes its geological & geochemical characteristics, summarizes its mineralizing rules, tries to set up mineralizing modes conforming to the actuality, expects to make a reference to mineralizing theory-building and ore-exploration.The research area is located in the west edge of Yangzi plate, has experienced tectonism for many times, outcropped strata are Proterozoic, Sinian, Triassi, Jurassic, Cretaceous and Quaternary, mainly Proterozoic Pudeng and Yangjiuhe rock groups; magma activity lasts very long and frequently, the lithology is complicated, acid granite of jinningian-Chengjiangian is mostly and widely distributed, basic or ultrabasic rock of variscan takes the second place; deformation and metamorphism is mainly jinningian-Chengjiangian extrusion or extension movement, the structural pattern is thus formed with main body of Yuanmou Metamorphic core complex and orientation of Yuanmou-Lvzhijiang fault zone.By rock and soil geochemistryl analysis and survey, the anomalies have been circled, Combined with the geologic factors including strata and structure, summed up 4 kinds of anomaly presumes with high economic value:Cu anomaly is controlled by meta-volcanic rocks from Pudeng group; Cu & Au anomaly is related to magma activity and not so obvious by structural control; Cu, Au, Pb and Zn anomalies is concerned with magma activity and distinctly controlled by the fault; Ni, Pt and Pd anomalies is closely related to ultrabasic rocks.The research area is popularized in mineralization and rich in mineral deposit type, there're mainly three types:volcano-sedimentary metamorphosed Copper-Iron deposit distributed in Pudeng group, hydrothermal metasomatic-filling type Copper Gold-polymetallic deposit distributed in ductile shear zone of Yuanmou metamorphosed core complex or Yuanmou fault zone, and magma-segregation platinum-palladium deposit distributed in basic or ultrabasic rocks.By summarizing its geological & geochemical characteristics, mineral deposit (occurrences) type and distributing rules, three mineralizing modes has been concluded as follows:magma-segregation platinum-palladium deposit ore-forming, volcano-sedimentary metamorphosed Copper-Iron deposit ore-forming, hydrothermal metasomatic-filling type Copper Gold-polymetallic deposit ore-forming. It lays a theoretic foundation for exploration & development of mineral resources in this area.Based on the knowledge of geological & geochemical characteristics, mineralizing process and modes in Yuanmou district, it's proposed to look for metamorphosed Copper-Iron deposit in Pudeng rock group around Asagu, search for hydrothermal metasomatic-filling type Copper Gold-polymetallic deposit in ductile shear zone of Yuanmou metamorphosed core complex or Yuanmou-Lvyejiang fault zone and its sub-fault, explore magma-differentiated platinum-palladium deposit in ultrabasic rocks around Heini.