Metallogenetic Regularities And Prediction Of Porphyry Copper Deposits In Middle-east Of Gangdese, Tibet

Based on the Theory of Plate Tectonic and detailed discussion of Gangdese, we study the geologic settings, ore deposit features and geochemical characteristics of three typical ore deposits, we confirmed their genesis. After a comprehensive comparison, we concluded the metallotect, ore-forming regularity and models. Further, we put forward an analogical predication.In this thesis, we distinguished the similarities and differences among Xiogncun, Jiama and Chongjiang Porphyry Ore Deposit. Considering they formed almost at the same time and geologic setting, the genetic differences suggest the metallogenetic complexity. Jiama and Chongjiang are Cu-Mo porphyry ore deposit, while the Xiongcun is Cu-Au porphyry ore deposit.The Xiongcun porphyry is a island arc type, while the Jiama and Chongjiang belong to post-orogenic stage. Although inferior position of Xiongcun, it also has ore prospecting potentiality.Tectonic settings of the three ore deposits are similar. They are all controlled by faults which parallel the Brahmaputra suture zone. In a smaller scale, Jiama and Chonjiang are constrained by pullapart faults which are south-north. This suggests that the tectonic and structures are important in the ore-forming process.After a summary on the geochemistry, magma source, structures, wall-rocks, alternation as well as mineralization, we put forward a re-forming regularity about the east zone of Gangdese. The geochemical similarity of Jiama and Chonjiang, show that they may derive from a alike magma source (Although Jima developed skarn while the Chonjiang has no sharn). Then we confirmed the metallogenetic model of the Xiongcun and Jiama. After extract required prospecting elements and geophysical-geochemical exploration, we give a ore prospecting using analogical predication on the workbench of MapGIS.