Geochronological studies on the crust-derived Tianmenshan pluton were undertaken by SHRIMP zircon U-Pb dating and Ar-Ar dating of biotite,muscovite and K-feldspar,giving a petrogenetic age of 167 Ma.Owing to the closu...Geochronological studies on the crust-derived Tianmenshan pluton were undertaken by SHRIMP zircon U-Pb dating and Ar-Ar dating of biotite,muscovite and K-feldspar,giving a petrogenetic age of 167 Ma.Owing to the closure systems in different minerals,the cooling history of the pluton can be determined with an age-temperature diagram.The late hydrothermal event has been recognized,which is related probably with mineralization.In terms of the comparative geochronological and petrologic records,it is concluded that there are some constrains on tectonic evolution and that the formation of the Tianmenshan pluton proceeded in a transition period from Indosinian post-orogeny extension to strong compressive tectonics.And the timing of the hydrothermal event matches the compressive climax of the Yanshanian orogeny.The temporal gap between granite emplacement and wolframite mineralization could last 10-20 Ma owing to the low cooling rate of the pluton.展开更多
Jiangxi Province, China's largest base tbr tungsten production and export is known as the world capital of tungsten. By the end of 2002, there were 72 primary tungsten deposits tbund, with accumulated reserves and a ...Jiangxi Province, China's largest base tbr tungsten production and export is known as the world capital of tungsten. By the end of 2002, there were 72 primary tungsten deposits tbund, with accumulated reserves and a proven resource of reserves of 1.9 Mt and 1.12 Mt, respectively, accounting for 20 percent of China's total reserves.展开更多
The Piaotang tungsten deposit in Jiangxi Province is one of the most important tungsten deposits in the South China Tungsten Metallogenic Province.In this study,we selected wolframite and chalcopyrite from the main mi...The Piaotang tungsten deposit in Jiangxi Province is one of the most important tungsten deposits in the South China Tungsten Metallogenic Province.In this study,we selected wolframite and chalcopyrite from the main mineralizing stage of the Piaotang tungsten deposit,and analyzed the helium and argon isotopic compositions in fluid inclusions of these minerals.The results show a 3He/4He ratio of 0.17 to 0.86 R/Ra,which fall within the range between continental crust(0.01―0.05 R/Ra) and air-saturated water(1 R/Ra) ,but are significantly lower than those of the normal mantle(6―9 R/Ra) .Their 40 Ar/36 Ar ratios are between 354.5 and 590.7,which are slightly higher than the air-saturated water(295.5) .Along with the other geochemical observation such as the lithium enrichments in the ore bodies and the ore-related granites,we suggest that the ore-forming fluid in the Piaotang tungsten deposit was mainly derived from crustal fluid.It may have mixed with some amounts of air-saturated water,but there was no considerable involvement of mantle-derived fluid.展开更多
文摘Geochronological studies on the crust-derived Tianmenshan pluton were undertaken by SHRIMP zircon U-Pb dating and Ar-Ar dating of biotite,muscovite and K-feldspar,giving a petrogenetic age of 167 Ma.Owing to the closure systems in different minerals,the cooling history of the pluton can be determined with an age-temperature diagram.The late hydrothermal event has been recognized,which is related probably with mineralization.In terms of the comparative geochronological and petrologic records,it is concluded that there are some constrains on tectonic evolution and that the formation of the Tianmenshan pluton proceeded in a transition period from Indosinian post-orogeny extension to strong compressive tectonics.And the timing of the hydrothermal event matches the compressive climax of the Yanshanian orogeny.The temporal gap between granite emplacement and wolframite mineralization could last 10-20 Ma owing to the low cooling rate of the pluton.
文摘Jiangxi Province, China's largest base tbr tungsten production and export is known as the world capital of tungsten. By the end of 2002, there were 72 primary tungsten deposits tbund, with accumulated reserves and a proven resource of reserves of 1.9 Mt and 1.12 Mt, respectively, accounting for 20 percent of China's total reserves.
基金supported by the National Natural Science Foundation of China(Grant No.40221301)
文摘The Piaotang tungsten deposit in Jiangxi Province is one of the most important tungsten deposits in the South China Tungsten Metallogenic Province.In this study,we selected wolframite and chalcopyrite from the main mineralizing stage of the Piaotang tungsten deposit,and analyzed the helium and argon isotopic compositions in fluid inclusions of these minerals.The results show a 3He/4He ratio of 0.17 to 0.86 R/Ra,which fall within the range between continental crust(0.01―0.05 R/Ra) and air-saturated water(1 R/Ra) ,but are significantly lower than those of the normal mantle(6―9 R/Ra) .Their 40 Ar/36 Ar ratios are between 354.5 and 590.7,which are slightly higher than the air-saturated water(295.5) .Along with the other geochemical observation such as the lithium enrichments in the ore bodies and the ore-related granites,we suggest that the ore-forming fluid in the Piaotang tungsten deposit was mainly derived from crustal fluid.It may have mixed with some amounts of air-saturated water,but there was no considerable involvement of mantle-derived fluid.