The tectono-magmatism in eastern China is a hotspot for the researches, and many hypotheses of that were discussed. There is a middle crust with solid, low velocity and high conductivity in eastern China, which is imp...The tectono-magmatism in eastern China is a hotspot for the researches, and many hypotheses of that were discussed. There is a middle crust with solid, low velocity and high conductivity in eastern China, which is impossible to form"convection magmatic layer". The subduction and compression of oceanic plate induced to the lateral pressure for the eastern China lithosphere in the condition of increasing pressure and decreasing temperature, it is also impossible to form an extensively melting magma layer. In South China, the granitic zone migrates from west to east, their evolution cannot be explained by plate subduction. The original magmatic reservoirs are controlled by main faults and spheres, which occurred the tectonic detachment and formed in the process of decreasing pressure and increasing temperature. The magma only originates in very small part of lithosphere. The tectono-magmatism and tectonic detachment of eastern China lithosphere during the Jurassic and the Cretaceous are concentrate mainly near the intersections between the regional faults and middle crust or the Moho discontinuity, and then magma intrudes or erupts along faults. The tectono-magmatism of Cenozoic originates near the intersections between the regional high-angle normal faults and the bottom of lithosphere. Obviously, the different penetration depth of faults induces a different kind of magmatism.展开更多
In the Middle Jurassic,a large-scale tectonic-magmatic activities and hydrothermal mineralization occurred in the eastern Jilin province.The deposit types consist of the orogenic gold deposit,porphyry molybdenum depos...In the Middle Jurassic,a large-scale tectonic-magmatic activities and hydrothermal mineralization occurred in the eastern Jilin province.The deposit types consist of the orogenic gold deposit,porphyry molybdenum deposit and skarn gold deposit,etc.,which constitute regional hydrothermal metallogenic series.The magmatic bodies related to mineralization belong to calc-alkaline series,which are characterized by active continental margins.The above-mentioned different types of deposits formed in a uniform tectonic setting,which resulted from the combined processes between the subduction of Pacific plate under the Eurasia plate and the persistent post-collisional convergent forces between the North China plate and the Siberian plate.The mineralizations were happening in the deceleration period,after which Paleo-Pacific plate was strongly subducted under the Eurasia continental block,i.e.transition period from compression to extension.展开更多
The Wenquan molybdenum deposit is a kind of large-sized porphyry molybdenum deposit found in re-cent years.In this paper,on the basis of deposit geology,geochemistry and isotope geochronology data,the metal-logenic mo...The Wenquan molybdenum deposit is a kind of large-sized porphyry molybdenum deposit found in re-cent years.In this paper,on the basis of deposit geology,geochemistry and isotope geochronology data,the metal-logenic model of this deposit was established.The Wenquan granitic batholith belongs to the K-rich(alkali-rich) calc-alkaline rock series,which is the mineralization parent rock.The rock massif shows the characteristics of both crust-remelting granite and mantle-source granite.At the same time,the data of REE contents,hydrogen and oxygen isotopes and inclusion temperatures showed that the metallogenic hydrothermal solution is a mixed mesothermal solution of magmato-hydrothermal fluid and meteoric water.Mineralization was dated at 214±7.1 Ma,basically identical with the parent rock's age(207-226 Ma).This reflects that molybdenum mineralization has a close relation to tectonic magmatism evoked by orogenic processes,and molybdenum mineralization occurred mainly at the petrogenesis stage at the late stage of magma emplacement.Mixing with meteoric water led to a decrease in the sa-linity of magmato-hydrothermal solution and changes in other physical and chemical properties.During the tectonic process,ore-bearing hydrothermal solution ascended along favorable fault structure channels.With physicochemical changes,it filled in the surrounding rock joints on both sides of faults,forming ore deposits.展开更多
文摘The tectono-magmatism in eastern China is a hotspot for the researches, and many hypotheses of that were discussed. There is a middle crust with solid, low velocity and high conductivity in eastern China, which is impossible to form"convection magmatic layer". The subduction and compression of oceanic plate induced to the lateral pressure for the eastern China lithosphere in the condition of increasing pressure and decreasing temperature, it is also impossible to form an extensively melting magma layer. In South China, the granitic zone migrates from west to east, their evolution cannot be explained by plate subduction. The original magmatic reservoirs are controlled by main faults and spheres, which occurred the tectonic detachment and formed in the process of decreasing pressure and increasing temperature. The magma only originates in very small part of lithosphere. The tectono-magmatism and tectonic detachment of eastern China lithosphere during the Jurassic and the Cretaceous are concentrate mainly near the intersections between the regional faults and middle crust or the Moho discontinuity, and then magma intrudes or erupts along faults. The tectono-magmatism of Cenozoic originates near the intersections between the regional high-angle normal faults and the bottom of lithosphere. Obviously, the different penetration depth of faults induces a different kind of magmatism.
文摘In the Middle Jurassic,a large-scale tectonic-magmatic activities and hydrothermal mineralization occurred in the eastern Jilin province.The deposit types consist of the orogenic gold deposit,porphyry molybdenum deposit and skarn gold deposit,etc.,which constitute regional hydrothermal metallogenic series.The magmatic bodies related to mineralization belong to calc-alkaline series,which are characterized by active continental margins.The above-mentioned different types of deposits formed in a uniform tectonic setting,which resulted from the combined processes between the subduction of Pacific plate under the Eurasia plate and the persistent post-collisional convergent forces between the North China plate and the Siberian plate.The mineralizations were happening in the deceleration period,after which Paleo-Pacific plate was strongly subducted under the Eurasia continental block,i.e.transition period from compression to extension.
文摘The Wenquan molybdenum deposit is a kind of large-sized porphyry molybdenum deposit found in re-cent years.In this paper,on the basis of deposit geology,geochemistry and isotope geochronology data,the metal-logenic model of this deposit was established.The Wenquan granitic batholith belongs to the K-rich(alkali-rich) calc-alkaline rock series,which is the mineralization parent rock.The rock massif shows the characteristics of both crust-remelting granite and mantle-source granite.At the same time,the data of REE contents,hydrogen and oxygen isotopes and inclusion temperatures showed that the metallogenic hydrothermal solution is a mixed mesothermal solution of magmato-hydrothermal fluid and meteoric water.Mineralization was dated at 214±7.1 Ma,basically identical with the parent rock's age(207-226 Ma).This reflects that molybdenum mineralization has a close relation to tectonic magmatism evoked by orogenic processes,and molybdenum mineralization occurred mainly at the petrogenesis stage at the late stage of magma emplacement.Mixing with meteoric water led to a decrease in the sa-linity of magmato-hydrothermal solution and changes in other physical and chemical properties.During the tectonic process,ore-bearing hydrothermal solution ascended along favorable fault structure channels.With physicochemical changes,it filled in the surrounding rock joints on both sides of faults,forming ore deposits.
